Mapping severe fire potential across the contiguous United States

Treesearch

Brett H. Davis

2016-01-01

The Fire Severity Mapping System (FIRESEV) project is an effort to provide critical information and tools to fire managers that enhance their ability to assess potential ecological effects of wildland fire. A major component of FIRESEV is the development of a Severe Fire Potential Map (SFPM), a geographic dataset covering the contiguous United States (CONUS) that...

Safety. Fire Service Certification Series. Unit FSCS-FF-2-80.

ERIC Educational Resources Information Center

Pribyl, Paul F.

This training unit on safety is part of a 17-unit course package written to aid instructors in the development, teaching, and evaluation of fire fighters in the Wisconsin Fire Service Certification Series. The purpose stated for the 4-hour unit is to assist firefighters in understanding the hazards of their profession and some methods of reducing…

Operating room fire prevention: creating an electrosurgical unit fire safety device.

PubMed

Culp, William C; Kimbrough, Bradly A; Luna, Sarah; Maguddayao, Aris J

2014-08-01

To reduce the incidence of surgical fires. Operating room fires represent a potentially life-threatening hazard and are triggered by the electrosurgical unit (ESU) pencil. Carbon dioxide is a fire suppressant and is a routinely used medical gas. We hypothesize that a shroud of protective carbon dioxide covering the tip of the ESU pencil displaces oxygen, thereby preventing fire ignition. Using 3-dimensional modeling techniques, a polymer sleeve was created and attached to an ESU pencil. This sleeve was connected to a carbon dioxide source and directed the gas through multiple precisely angled ports, generating a cone of fire-suppressive carbon dioxide surrounding the active pencil tip. This device was evaluated in a flammability test chamber containing 21%, 50%, and 100% oxygen with sustained ESU activation. The sleeve was tested with and without carbon dioxide (control) until a fuel was ignited or 30 seconds elapsed. Time to ignition was measured by high-speed videography. Fires were ignited with each control trial (15/15 trials). The control group median ± SD ignition time in 21% oxygen was 3.0 ± 2.4 seconds, in 50% oxygen was 0.1 ± 1.8 seconds, and in 100% oxygen was 0.03 ± 0.1 seconds. No fire was observed when the fire safety device was used in all concentrations of oxygen (0/15 trials; P < 0.0001). The exact 95% confidence interval for absolute risk reduction of fire ignition was 76% to 100%. A sleeve creating a cone of protective carbon dioxide gas enshrouding the sparks from an ESU pencil effectively prevents fire in a high-flammability model. Clinical application of this device may reduce the incidence of operating room fires.

Contribution from motor unit firing adaptations and muscle co-activation during fatigue.

PubMed

Contessa, Paola; Letizi, John; De Luca, Gianluca; Kline, Joshua C

2018-03-14

The control of motor unit firing behavior during fatigue is still debated in the literature. Most studies agree that the central nervous system increases the excitation to the motoneuron pool to compensate for decreased force contributions of individual motor units and sustain muscle force output during fatigue. However, some studies claim that motor units may decrease their firing rates despite increased excitation, contradicting the direct relationship between firing rates and excitation that governs the voluntary control of motor units. To investigate whether the control of motor units in fact changes with fatigue, we measured motor unit firing behavior during repeated contractions of the first dorsal interosseous (FDI) muscle while concurrently monitoring the activation of surrounding muscles - including the flexor carpi radialis, extensor carpi radialis, and pronator teres. Across all subjects, we observed an overall increase in FDI activation and motor unit firing rates by the end of the fatigue task. However, in some subjects we observed increases in FDI activation and motor unit firing rates only during the initial phase of the fatigue task, followed by subsequent decreases during the late phase of the fatigue task while the co-activation of surrounding muscles increased. These findings indicate that the strategy for sustaining force output may occasionally change leading to increases in the relative activation of surrounding muscles while the excitation to the fatiguing muscle decreases. Importantly, irrespective of changes in the strategy for sustaining force output, the control properties regulating motor unit firing behavior remain unchanged during fatigue.

Human-started wildfires expand the fire niche across the United States.

PubMed

Balch, Jennifer K; Bradley, Bethany A; Abatzoglou, John T; Nagy, R Chelsea; Fusco, Emily J; Mahood, Adam L

2017-03-14

The economic and ecological costs of wildfire in the United States have risen substantially in recent decades. Although climate change has likely enabled a portion of the increase in wildfire activity, the direct role of people in increasing wildfire activity has been largely overlooked. We evaluate over 1.5 million government records of wildfires that had to be extinguished or managed by state or federal agencies from 1992 to 2012, and examined geographic and seasonal extents of human-ignited wildfires relative to lightning-ignited wildfires. Humans have vastly expanded the spatial and seasonal "fire niche" in the coterminous United States, accounting for 84% of all wildfires and 44% of total area burned. During the 21-y time period, the human-caused fire season was three times longer than the lightning-caused fire season and added an average of 40,000 wildfires per year across the United States. Human-started wildfires disproportionally occurred where fuel moisture was higher than lightning-started fires, thereby helping expand the geographic and seasonal niche of wildfire. Human-started wildfires were dominant (>80% of ignitions) in over 5.1 million km 2 , the vast majority of the United States, whereas lightning-started fires were dominant in only 0.7 million km 2 , primarily in sparsely populated areas of the mountainous western United States. Ignitions caused by human activities are a substantial driver of overall fire risk to ecosystems and economies. Actions to raise awareness and increase management in regions prone to human-started wildfires should be a focus of United States policy to reduce fire risk and associated hazards.

Portable light source unit for simulating fires having an adjustable aperture

NASA Technical Reports Server (NTRS)

Youngquist, Robert C. (Inventor); Moerk, John S. (Inventor); Strobel, James P. (Inventor)

1997-01-01

A portable, hand held light source unit is employed to check operation of fire detectors, such as hydrogen fire detectors. The unit emits radiation in a narrow band of wavelengths which are generated by the type of fire to be tested, but not by other light sources such as the sun or incandescent lamps. The unit can test fire detectors at different distances, and of different sensitivities. The intensity of the radiation emitted by the unit is adjustable for this purpose by means of a rotatable disk having a plurality of different sized apertures for selective placement between the light source and an output lens. The disk can also be rotated to a calibration position which causes a microprocessor circuit in the unit to initiate a calibration procedure. During this procedure, the lamp intensity is measured by a photodetector contained within the unit, and the microprocessor adjusts the lamp current to insure that its intensity remains within a preset range of values. A green and a red LED are mounted on the unit which indicate to an operator whether the calibration is successful, as well as the condition of the unit's battery power supply.

The compensatory interaction between motor unit firing behavior and muscle force during fatigue

PubMed Central

De Luca, Carlo J.; Kline, Joshua C.

2016-01-01

Throughout the literature, different observations of motor unit firing behavior during muscle fatigue have been reported and explained with varieties of conjectures. The disagreement amongst previous studies has resulted, in part, from the limited number of available motor units and from the misleading practice of grouping motor unit data across different subjects, contractions, and force levels. To establish a more clear understanding of motor unit control during fatigue, we investigated the firing behavior of motor units from the vastus lateralis muscle of individual subjects during a fatigue protocol of repeated voluntary constant force isometric contractions. Surface electromyographic decomposition technology provided the firings of 1,890 motor unit firing trains. These data revealed that to sustain the contraction force as the muscle fatigued, the following occurred: 1) motor unit firing rates increased; 2) new motor units were recruited; and 3) motor unit recruitment thresholds decreased. Although the degree of these adaptations was subject specific, the behavior was consistent in all subjects. When we compared our empirical observations with those obtained from simulation, we found that the fatigue-induced changes in motor unit firing behavior can be explained by increasing excitation to the motoneuron pool that compensates for the fatigue-induced decrease in muscle force twitch reported in empirical studies. Yet, the fundamental motor unit control scheme remains invariant throughout the development of fatigue. These findings indicate that the central nervous system regulates motor unit firing behavior by adjusting the operating point of the excitation to the motoneuron pool to sustain the contraction force as the muscle fatigues. PMID:27385798

The compensatory interaction between motor unit firing behavior and muscle force during fatigue.

PubMed

Contessa, Paola; De Luca, Carlo J; Kline, Joshua C

2016-10-01

Throughout the literature, different observations of motor unit firing behavior during muscle fatigue have been reported and explained with varieties of conjectures. The disagreement amongst previous studies has resulted, in part, from the limited number of available motor units and from the misleading practice of grouping motor unit data across different subjects, contractions, and force levels. To establish a more clear understanding of motor unit control during fatigue, we investigated the firing behavior of motor units from the vastus lateralis muscle of individual subjects during a fatigue protocol of repeated voluntary constant force isometric contractions. Surface electromyographic decomposition technology provided the firings of 1,890 motor unit firing trains. These data revealed that to sustain the contraction force as the muscle fatigued, the following occurred: 1) motor unit firing rates increased; 2) new motor units were recruited; and 3) motor unit recruitment thresholds decreased. Although the degree of these adaptations was subject specific, the behavior was consistent in all subjects. When we compared our empirical observations with those obtained from simulation, we found that the fatigue-induced changes in motor unit firing behavior can be explained by increasing excitation to the motoneuron pool that compensates for the fatigue-induced decrease in muscle force twitch reported in empirical studies. Yet, the fundamental motor unit control scheme remains invariant throughout the development of fatigue. These findings indicate that the central nervous system regulates motor unit firing behavior by adjusting the operating point of the excitation to the motoneuron pool to sustain the contraction force as the muscle fatigues. Copyright © 2016 the American Physiological Society.

Human-started wildfires expand the fire niche across the United States

PubMed Central

Balch, Jennifer K.; Bradley, Bethany A.; Nagy, R. Chelsea; Fusco, Emily J.; Mahood, Adam L.

2017-01-01

The economic and ecological costs of wildfire in the United States have risen substantially in recent decades. Although climate change has likely enabled a portion of the increase in wildfire activity, the direct role of people in increasing wildfire activity has been largely overlooked. We evaluate over 1.5 million government records of wildfires that had to be extinguished or managed by state or federal agencies from 1992 to 2012, and examined geographic and seasonal extents of human-ignited wildfires relative to lightning-ignited wildfires. Humans have vastly expanded the spatial and seasonal “fire niche” in the coterminous United States, accounting for 84% of all wildfires and 44% of total area burned. During the 21-y time period, the human-caused fire season was three times longer than the lightning-caused fire season and added an average of 40,000 wildfires per year across the United States. Human-started wildfires disproportionally occurred where fuel moisture was higher than lightning-started fires, thereby helping expand the geographic and seasonal niche of wildfire. Human-started wildfires were dominant (>80% of ignitions) in over 5.1 million km2, the vast majority of the United States, whereas lightning-started fires were dominant in only 0.7 million km2, primarily in sparsely populated areas of the mountainous western United States. Ignitions caused by human activities are a substantial driver of overall fire risk to ecosystems and economies. Actions to raise awareness and increase management in regions prone to human-started wildfires should be a focus of United States policy to reduce fire risk and associated hazards. PMID:28242690

Water Supply. Fire Service Certification Series. Unit FSCS-FF-9-80.

ERIC Educational Resources Information Center

Pribyl, Paul F.

This training unit on water supply is part of a 17-unit course package written to aid instructors in the development, teaching, and evaluation of fire fighters in the Wisconsin Fire Service Certification Series. The purpose stated for the 4-hour unit is to assist the firefighter in the proper use of water supplies and the understanding of the…

Prefrontal single-unit firing associated with deficient extinction in mice

PubMed Central

Fitzgerald, Paul J; Whittle, Nigel; Flynn, Shaun M; Graybeal, Carolyn; Pinard, Courtney; Gunduz-Cinar, Ozge; Kravitz, Alexxai; Singewald, Nicolas; Holmes, Andrew

2014-01-01

The neural circuitry mediating fear extinction has been increasingly well studied and delineated. The rodent infralimbic subregion (IL) of the ventromedial prefrontal cortex (vmPFC) has been found to promote extinction, whereas the prelimbic cortex (PL) demonstrates an opposing, pro-fear, function. Studies employing in vivo electrophysiological recordings have observed that while increased IL single-unit firing and bursting predicts robust extinction retrieval, increased PL firing can correlate with sustained fear and poor extinction. These relationships between single-unit firing and extinction do not hold under all experimental conditions, however. In the current study, we further investigated the relationship between vmPFC and PL single-unit firing and extinction using inbred mouse models of intact (C57BL/6J, B6) and deficient (129S1/SvImJ, S1) extinction strains. Simultaneous single-unit recordings were made in the PL and vmPFC (encompassing IL) as B6 and S1 mice performed extinction training and retrieval. Impaired extinction retrieval in S1 mice was associated with elevated PL single-unit firing, as compared to firing in extinguishing B6 mice, consistent with the hypothesized pro-fear contribution of PL. Analysis of local field potentials also revealed significantly higher gamma power in the PL of Sthan B6 mice during extinction training and retrieval. In the vmPFC, impaired extinction in S1 mice was also associated with exaggerated single-unit firing, relative to B6 mice. This is in apparent contradiction to evidence that IL activity promotes extinction, but could reflect a (failed) compensatory effort by the vmPFC to mitigate fear-promoting activity in other regions, such as the PL or amygdala. In support of this hypothesis, augmenting IL activity via direct infusion of the GABAA receptor antagonist picrotoxin rescued impaired extinction retrieval in S1 mice. Chronic fluoxetine treatment produced modest reductions in fear during extinction retrieval and

Sprinklers/Standpipes/Detection Systems. Fire Service Certification Series. Unit FSCS-FF-11-80.

ERIC Educational Resources Information Center

Pribyl, Paul F.

This training unit on sprinklers, standpipes, and detection systems is part of a 17-unit course package written to aid instructors in the development, teaching, and evaluation of fire fighters in the Wisconsin Fire Service Certification Series. The purpose stated for the 6-hour unit is to provide the fire fighter with an understanding of the…

Fire danger rating in the United States of America: An evolution since 1916

Treesearch

Colin C. Hardy; Charles E. Hardy

2007-01-01

Fire scientists in the United States began exploring the relationships of fire-danger and hazard with weather, fuel moisture, and ignition probabilities as early as 1916. Many of the relationships identified then persist today in the form of our National Fire-Danger-Rating System. This paper traces the evolution of fire-danger rating in the United States, including...

Utilizing multi-sensor fire detections to map fires in the United States

USGS Publications Warehouse

Howard, Stephen M.; Picotte, Joshua J.; Coan, Michael

2014-01-01

In 2006, the Monitoring Trends in Burn Severity (MTBS) project began a cooperative effort between the US Forest Service (USFS) and the U.S.Geological Survey (USGS) to map and assess burn severity all large fires that have occurred in the United States since 1984. Using Landsat imagery, MTBS is mandated to map wildfire and prescribed fire that meet specific size criteria: greater than 1000 acres in the west and 500 acres in the east, regardless of ownership. Relying mostly on federal and state fire occurrence records, over 15,300 individual fires have been mapped. While mapping recorded fires, an additional 2,700 “unknown” or undocumented fires were discovered and assessed. It has become apparent that there are perhaps thousands of undocumented fires in the US that are yet to be mapped. Fire occurrence records alone are inadequate if MTBS is to provide a comprehensive accounting of fire across the US. Additionally, the sheer number of fires to assess has overwhelmed current manual procedures. To address these problems, the National Aeronautics and Space Administration (NASA) Applied Sciences Program is helping to fund the efforts of the USGS and its MTBS partners (USFS, National Park Service) to develop, and implement a system to automatically identify fires using satellite data. In near real time, USGS will combine active fire satellite detections from MODIS, AVHRR and GOES satellites with Landsat acquisitions. Newly acquired Landsat imagery will be routinely scanned to identify freshly burned area pixels, derive an initial perimeter and tag the burned area with the satellite date and time of detection. Landsat imagery from the early archive will be scanned to identify undocumented fires. Additional automated fire assessment processes will be developed. The USGS will develop these processes using open source software packages in order to provide freely available tools to local land managers providing them with the capability to assess fires at the local level.

Utilizing Multi-Sensor Fire Detections to Map Fires in the United States

NASA Astrophysics Data System (ADS)

Howard, S. M.; Picotte, J. J.; Coan, M. J.

2014-11-01

In 2006, the Monitoring Trends in Burn Severity (MTBS) project began a cooperative effort between the US Forest Service (USFS) and the U.S.Geological Survey (USGS) to map and assess burn severity all large fires that have occurred in the United States since 1984. Using Landsat imagery, MTBS is mandated to map wildfire and prescribed fire that meet specific size criteria: greater than 1000 acres in the west and 500 acres in the east, regardless of ownership. Relying mostly on federal and state fire occurrence records, over 15,300 individual fires have been mapped. While mapping recorded fires, an additional 2,700 "unknown" or undocumented fires were discovered and assessed. It has become apparent that there are perhaps thousands of undocumented fires in the US that are yet to be mapped. Fire occurrence records alone are inadequate if MTBS is to provide a comprehensive accounting of fire across the US. Additionally, the sheer number of fires to assess has overwhelmed current manual procedures. To address these problems, the National Aeronautics and Space Administration (NASA) Applied Sciences Program is helping to fund the efforts of the USGS and its MTBS partners (USFS, National Park Service) to develop, and implement a system to automatically identify fires using satellite data. In near real time, USGS will combine active fire satellite detections from MODIS, AVHRR and GOES satellites with Landsat acquisitions. Newly acquired Landsat imagery will be routinely scanned to identify freshly burned area pixels, derive an initial perimeter and tag the burned area with the satellite date and time of detection. Landsat imagery from the early archive will be scanned to identify undocumented fires. Additional automated fire assessment processes will be developed. The USGS will develop these processes using open source software packages in order to provide freely available tools to local land managers providing them with the capability to assess fires at the local level.

Fire in the eastern United States: influence on wildlife habitat

Treesearch

D. H. Van Lear; R. F. Harlow

2002-01-01

Fire is a major influence shaping wildlife habitats in the eastern United States. Lightning- and Indian-ignited fires burned frequently and extensively over the pre-Columbian landscape and shaped the character of numerous ecosystems. Depending upon the frequency, intensity, and severity of the fires, various assemblages of plants developed along environmental gradients...

Fire - Southern Oscillation relations in the southwestern United States

USGS Publications Warehouse

Swetnam, T.W.; Betancourt, J.L.

1990-01-01

Fire scar and tree growth chronologies (1700 to 1905) and fire statistics (since 1905) from Arizona and New Mexico show that small areas burn after wet springs associated with the low phase of the Southern Oscillation (SO), whereas large areas burn after dry springs associated with the high phase of the SO. Through its synergistic influence on spring weather and fuel conditions, climatic variability in the tropical Pacific significantly influences vegetation dynamics in the southwestern United States. Synchrony of fire-free and severe fire years across diverse southwestern forests implies that climate forces fire regimes on a subcontinental scale; it also underscores the importance of exogenous factors in ecosystem dynamics.

Critical wind velocity for arresting upwind gas and smoke dispersion induced by near-wall fire in a road tunnel.

PubMed

Hu, L H; Peng, W; Huo, R

2008-01-15

In case of a tunnel fire, toxic gas and smoke particles released are the most fatal contaminations. It is important to supply fresh air from the upwind side to provide a clean and safe environment upstream from the fire source for people evacuation. Thus, the critical longitudinal wind velocity for arresting fire induced upwind gas and smoke dispersion is a key criteria for tunnel safety design. Former studies and thus, the models built for estimating the critical wind velocity are all arbitrarily assuming that the fire takes place at the centre of the tunnel. However, in many real cases in road tunnels, the fire originates near the sidewall. The critical velocity of a near-wall fire should be different with that of a free-standing central fire due to their different plume entrainment process. Theoretical analysis and CFD simulation were performed in this paper to estimate the critical velocity for the fire near the sidewall. Results showed that when fire originates near the sidewall, it needs larger critical velocity to arrest the upwind gas and smoke dispersion than when fire at the centre. The ratio of critical velocity of a near-wall fire to that of a central fire was ideally estimated to be 1.26 by theoretical analysis. Results by CFD modelling showed that the ratio decreased with the increase of the fire size till near to unity. The ratio by CFD modelling was about 1.18 for a 500kW small fire, being near to and a bit lower than the theoretically estimated value of 1.26. However, the former models, including those of Thomas (1958, 1968), Dangizer and Kenndey (1982), Oka and Atkinson (1995), Wu and Barker (2000) and Kunsch (1999, 2002), underestimated the critical velocity needed for a fire near the tunnel sidewall.

The minimal flow unit in near-wall turbulence

NASA Technical Reports Server (NTRS)

Jimeez, Javier; Moin, Parviz

1991-01-01

Direct numerical simulations of unsteady channel flow were performed at low to moderate Reynolds numbers on computational boxes chosen small enough so that the flow consists of a doubly periodic (in x and z) array of identical structures. The goal is to isolate the basic flow unit, to study its morphology and dynamics, and to evaluate its contribution to turbulence in fully developed channels. For boxes wider than approximately 100 wall units in the spanwise direction, the flow is turbulent, and the low-order turbulence statistics are in good agreement with experiments in the near-wall region. For a narrow range of widths below that threshold, the flow near only one wall remains turbulent, but its statistics are still in fairly good agreement with experimental data when scaled with the local wall stress. For narrower boxes only laminar solutions are found. In all cases, the elementary box contains a single low-velocity streak, consisting of a longitudinal strip on which a thin layer of spanwise vorticity is lifted away from the wall.

Mid-21st- century climate changes increase predicted fire occurrence and fire season length, Northern Rocky Mountains, United States

Treesearch

Karin L. Riley; Rachel A. Loehman

2016-01-01

Climate changes are expected to increase fire frequency, fire season length, and cumulative area burned in the western United States. We focus on the potential impact of mid-21st- century climate changes on annual burn probability, fire season length, and large fire characteristics including number and size for a study area in the Northern Rocky Mountains....

500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide emissions from coal-fired boilers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sorge, J.N.; Larrimore, C.L.; Slatsky, M.D.

1997-12-31

This paper discusses the technical progress of a US Department of Energy Innovative Clean Coal Technology project demonstrating advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The primary objectives of the demonstration is to determine the long-term NOx reduction performance of advanced overfire air (AOFA), low NOx burners (LNB), and advanced digital control optimization methodologies applied in a stepwise fashion to a 500 MW boiler. The focus of this paper is to report (1) on the installation of three on-line carbon-in-ash monitors and (2) the design and results to date from the advancedmore » digital control/optimization phase of the project.« less

Room fire test for fire growth modeling : a sensitivity study

Treesearch

H. C. Tran; M. L. Janssens

1989-01-01

A room test designed according to the ASTM draft standard was used to investigate the effect of various parameters on the contribution of wall and corner fires to compartment fire growth. Location of the burner (against a wall or in a corner), power program of the gas burner ignition source, and combination of wall linings were varied, An initial series of calibration...

Detection rates of the MODIS active fire product in the United States

USGS Publications Warehouse

Hawbaker, T.J.; Radeloff, V.C.; Syphard, A.D.; Zhu, Z.; Stewart, S.I.

2008-01-01

MODIS active fire data offer new information about global fire patterns. However, uncertainties in detection rates can render satellite-derived fire statistics difficult to interpret. We evaluated the MODIS 1??km daily active fire product to quantify detection rates for both Terra and Aqua MODIS sensors, examined how cloud cover and fire size affected detection rates, and estimated how detection rates varied across the United States. MODIS active fire detections were compared to 361 reference fires (??? 18??ha) that had been delineated using pre- and post-fire Landsat imagery. Reference fires were considered detected if at least one MODIS active fire pixel occurred within 1??km of the edge of the fire. When active fire data from both Aqua and Terra were combined, 82% of all reference fires were found, but detection rates were less for Aqua and Terra individually (73% and 66% respectively). Fires not detected generally had more cloudy days, but not when the Aqua data were considered exclusively. MODIS detection rates decreased with fire size, and the size at which 50% of all fires were detected was 105??ha when combining Aqua and Terra (195??ha for Aqua and 334??ha for Terra alone). Across the United States, detection rates were greatest in the West, lower in the Great Plains, and lowest in the East. The MODIS active fire product captures large fires in the U.S. well, but may under-represent fires in areas with frequent cloud cover or rapidly burning, small, and low-intensity fires. We recommend that users of the MODIS active fire data perform individual validations to ensure that all relevant fires are included. ?? 2008 Elsevier Inc. All rights reserved.

Mapping relative fire regime condition class for the Western United States

Treesearch

James P. Menakis; Melanie Miller; Thomas Thompson

2004-01-01

In 1999, a coarse-scale map of Fire Regime Condition Classes (FRCC) was developed for the conterminous United States (US) to help address contemporary fire management issues and to quantify changes in fuels from historical conditions. This map and its associated data have been incorporated into national policies (National Fire Plan, Forest Health Initiative) and...

The demise of fire and "mesophication" of forests in the eastern United States

Treesearch

Gregory J. Nowacki; Marc D. Abrams

2008-01-01

A diverse array of fire-adapted plant communities once covered the eastern United States. European settlement greatly altered fire regimes, often increasing fire occurrence (e.g., in northern hardwoods) or substantially decreasing it (e.g., in tallgrass prairies). Notwithstanding these changes, fire suppression policies, beginning around the 1920s, greatly reduced fire...

Advancing dendrochronological studies of fire in the United States

USGS Publications Warehouse

Harley, Grant L.; Baisan, Christopher H.; Brown, Peter M.; Falk, Donald A.; Flatley, William T.; Grissino-Mayer, Henri D.; Hessl, Amy; Heyerdahl, Emily K.; Kaye, Margot W.; Lafon, Charles W.; Margolis, Ellis; Maxwell, R. Stockton; Naito, Adam T.; Platt, William J.; Rother, Monica T.; Saladyga, Thomas; Sherriff, Rosemary L.; Stachowiak, Lauren A.; Stambaugh, Michael C.; Sutherland, Elaine Kennedy; Taylor, Alan H.

2018-01-01

Dendroecology is the science that dates tree rings to their exact calendar year of formation to study processes that influence forest ecology (e.g., Speer 2010, Amoroso et al., 2017). Reconstruction of past fire regimes is a core application of dendroecology, linking fire history to population dynamics and climate effects on tree growth and survivorship. Since the early 20th century when dendrochronologists recognized that tree rings retained fire scars (e.g., Figure 1), and hence a record of past fires, they have conducted studies worldwide to reconstruct the historical range and variability of fire regimes (e.g., frequency, severity, seasonality, spatial extent), the influence of fire regimes on forest structure and ecosystem dynamics, and the top-down (e.g., climate) and bottom-up (e.g., fuels, topography) drivers of fire that operate at a range of temporal and spatial scales. As in other scientific fields, continued application of dendrochronological techniques to study fires has shaped new trajectories for the science. Here we highlight some important current directions in the United States (US) and call on our international colleagues to continue the conversation with perspectives from other countries.

Wildland fire use: the dilemma of managing and restoring natural fire and fuels in United States wilderness

Treesearch

David J. Parsons; Peter B. Landres; Carol Miller

2003-01-01

The management of natural fire and fuels in wilderness areas of the United States presents a significant dilemma to federal land managers.Wilderness fire management requires balancing mandates to both preserve natural conditions and minimize the impacts of human activities.It also requires consideration of ecological and social values both within and outside of...

Large-scale, thick, self-assembled, nacre-mimetic brick-walls as fire barrier coatings on textiles

NASA Astrophysics Data System (ADS)

Das, Paramita; Thomas, Helga; Moeller, Martin; Walther, Andreas

2017-01-01

Highly loaded polymer/clay nanocomposites with layered structures are emerging as robust fire retardant surface coatings. However, time-intensive sequential deposition processes, e.g. layer-by-layer strategies, hinders obtaining large coating thicknesses and complicates an implementation into existing technologies. Here, we demonstrate a single-step, water-borne approach to prepare thick, self-assembling, hybrid fire barrier coatings of sodium carboxymethyl cellulose (CMC)/montmorillonite (MTM) with well-defined, bioinspired brick-wall nanostructure, and showcase their application on textile. The coating thickness on the textile is tailored using different concentrations of CMC/MTM (1-5 wt%) in the coating bath. While lower concentrations impart conformal coatings of fibers, thicker continuous coatings are obtained on the textile surface from highest concentration. Comprehensive fire barrier and fire retardancy tests elucidate the increasing fire barrier and retardancy properties with increasing coating thickness. The materials are free of halogen and heavy metal atoms, and are sourced from sustainable and partly even renewable building blocks. We further introduce an amphiphobic surface modification on the coating to impart oil and water repellency, as well as self-cleaning features. Hence, our study presents a generic, environmentally friendly, scalable, and one-pot coating approach that can be introduced into existing technologies to prepare bioinspired, thick, fire barrier nanocomposite coatings on diverse surfaces.

Fires in Southeast United States Both Wild and Prescribed

NASA Image and Video Library

2017-12-08

Fires both wild and prescribed dot the landscape of the southeastern portion of the United States. Wildfires are those that occur naturally with lightning strikes or are set by careless humans. Prescribed fires are those deliberately set by land management authorities to take out underlying brush and dead grass so that in the event of a wildfire there is not sufficient fuel for that fire to spread too far. The Southern Area Coordination Center for fire management has this information on its report for February 21, 2017. • Fires that have broken out recently (known as Initial Attack Activity): 198 fires for 2,292 acres • Ongoing Uncontained Large Fires: 3 fires for 5,947 acres • Other Fires reported through alternate channels: 56 fires for 1,400 acres • Prescribed Fire Activity: State and/or Federal Lands – 1,974 prescribed fires for 38,533 acres in AL, FL & GA The bulk of the fires seen in the image taken by the Aqua satellite using the onboard MODIS (Moderate Resolution Imaging Spectroradiometer) instrument on February 16, 2017 appear to be prescribed fires. Actively burning areas, detected by MODIS’s thermal bands, are outlined in red and when combined with smoke are indicative of fire. NASA image courtesy Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC. Caption by Lynn Jenner with information from the Southern Area Coordination Center. NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Demonstration of natural gas reburn for NO{sub x} emissions reduction at Ohio Edison Company`s cyclone-fired Niles Plant Unit Number 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borio, R.W.; Lewis, R.D.; Koucky, R.W.

1996-04-01

Electric utility power plants account for about one-third of the NO{sub x} and two-thirds of the SO{sub 2} emissions in the US cyclone-fired boilers, while representing about 9% of the US coal-fired generating capacity, emit about 14% of the NO{sub x} produced by coal-fired utility boilers. Given this background, the Environmental Protection Agency, the Gas Research Institute, the Electric Power Research Institute, the Pittsburgh Energy Technology Center, and the Ohio Coal Development Office sponsored a program led by ABB Combustion Engineering, Inc. (ABB-CE) to demonstrate reburning on a cyclone-fired boiler. Ohio Edison provided Unit No. 1 at their Niles Stationmore » for the reburn demonstration along with financial assistance. The Niles Unit No. 1 reburn system was started up in September 1990. This reburn program was the first full-scale reburn system demonstration in the US. This report describes work performed during the program. The work included a review of reburn technology, aerodynamic flow model testing of reburn system design concepts, design and construction of the reburn system, parametric performance testing, long-term load dispatch testing, and boiler tube wall thickness monitoring. The report also contains a description of the Niles No. 1 host unit, a discussion of conclusions and recommendations derived from the program, tabulation of data from parametric and long-term tests, and appendices which contain additional tabulated test results.« less

Mercury emission estimates from fires: an initial inventory for the United States.

PubMed

Wiedinmyer, Christine; Friedli, Hans

2007-12-01

Recent studies have shown that emissions of mercury (Hg), a hazardous air pollutant, from fires can be significant. However, to date, these emissions have not been well-quantified for the entire United States. Daily emissions of Hg from fires in the lower 48 states of the United States (LOWER48) and in Alaska were estimated for 2002-2006 using a simple fire emissions model. Emission factors of Hg from fires in different ecosystems were compiled from published plume studies and from soil-based assessments. Annual averaged emissions of Hg from fires in the LOWER48 and Alaska were 44 (20-65) metric tons yr(-1), equivalent to approximately 30% of the U.S. EPA 2002 National Emissions Inventory for Hg. Alaska had the highest averaged monthly emissions of all states; however, the emissions have a high temporal variability. Emissions from forests dominate the inventory, suggesting that Hg emissions from agricultural fires are not significant on an annual basis. The uncertainty in the Hg emission factors due to limited data leads to an uncertainty in the emission estimates on the order of +/-50%. Research is still needed to better constrain Hg emission factors from fires, particularly in the eastern U.S. and for ecosystems other than forests.

Large-scale, thick, self-assembled, nacre-mimetic brick-walls as fire barrier coatings on textiles

PubMed Central

Das, Paramita; Thomas, Helga; Moeller, Martin; Walther, Andreas

2017-01-01

Highly loaded polymer/clay nanocomposites with layered structures are emerging as robust fire retardant surface coatings. However, time-intensive sequential deposition processes, e.g. layer-by-layer strategies, hinders obtaining large coating thicknesses and complicates an implementation into existing technologies. Here, we demonstrate a single-step, water-borne approach to prepare thick, self-assembling, hybrid fire barrier coatings of sodium carboxymethyl cellulose (CMC)/montmorillonite (MTM) with well-defined, bioinspired brick-wall nanostructure, and showcase their application on textile. The coating thickness on the textile is tailored using different concentrations of CMC/MTM (1–5 wt%) in the coating bath. While lower concentrations impart conformal coatings of fibers, thicker continuous coatings are obtained on the textile surface from highest concentration. Comprehensive fire barrier and fire retardancy tests elucidate the increasing fire barrier and retardancy properties with increasing coating thickness. The materials are free of halogen and heavy metal atoms, and are sourced from sustainable and partly even renewable building blocks. We further introduce an amphiphobic surface modification on the coating to impart oil and water repellency, as well as self-cleaning features. Hence, our study presents a generic, environmentally friendly, scalable, and one-pot coating approach that can be introduced into existing technologies to prepare bioinspired, thick, fire barrier nanocomposite coatings on diverse surfaces. PMID:28054589

Fires Across the Western United States

NASA Technical Reports Server (NTRS)

2007-01-01

Days of record heat made the western United States tinder dry in early July 2007. Numerous wildfires raced across the dry terrain during the weekend of July 7. From Washington to Arizona, firefighters were battling fast-moving wildfires that threatened residences, businesses, gas wells, coal mines, communications equipment, and municipal watersheds. This image of the West was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite on Sunday, July 8. Places where MODIS detected actively burning fires are marked in red. Some of the largest blazes are labeled. Utah's Milford Flat was the largest; according to the July 9 morning report from the National Interagency Fire Center, the blaze was more than 280,000 acres, having grown more than 124,000 acres in the previous 24 hours. The fires have destroyed homes, forced evacuations, shut down trains and highways, and killed several people. Weather conditions were not expected to improve significantly across much of the area for several days, with hot temperatures and dry thunderstorms (lightning and winds, but little rain) likely in many places. Nearly the entire western United States was experiencing some level of drought as of July 3, according to the U.S. Drought Monitor. The drought had reached the 'extreme' category in southern California and western Arizona, and ranged from moderate to severe across most of the rest of the Southwest and Great Basin. The large image provided above has a spatial resolution (level of detail) of 500 meters per pixel. The MODIS Rapid Response Team provides twice-daily images of the region in additional resolutions and formats, including an infrared-enhanced version that makes burned terrain appear brick red. NASA image courtesy the MODIS Rapid Response Team, Goddard Space Flight Center

Determinants of Post-fire Water Quality in the Western United States

NASA Astrophysics Data System (ADS)

Rust, A.; Saxe, S.; Dolan, F.; Hogue, T. S.; McCray, J. E.

2015-12-01

Large wildfires are becoming increasingly common in the Western United States. Wildfires that consume greater than twenty percent of the watershed impact river water quality. The surface waters of the arid West are limited and in demand by the aquatic ecosystems, irrigated agriculture, and the region's growing human population. A range of studies, typically focused on individual fires, have observed mobilization of contaminants, nutrients (including nitrates), and sediments into receiving streams. Post-fire metal concentrations have also been observed to increase when fires were located in streams close to urban centers. The objective of this work was to assemble an extensive historical water quality database through data mining from federal, state and local agencies into a fire-database. Data from previous studies on individual fires by the co-authors was also included. The fire-database includes observations of water quality, discharge, geospatial and land characteristics from over 200 fire-impacted watersheds in the western U.S. since 1985. Water quality data from burn impacted watersheds was examined for trends in water quality response using statistical analysis. Watersheds where there was no change in water quality after fire were also examined to determine characteristics of the watershed that make it more resilient to fire. The ultimate goal is to evaluate trends in post-fire water quality response and identify key drivers of resiliency and post-fire response. The fire-database will eventually be publicly available.Large wildfires are becoming increasingly common in the Western United States. Wildfires that consume greater than twenty percent of the watershed impact river water quality. The surface waters of the arid West are limited and in demand by the aquatic ecosystems, irrigated agriculture, and the region's growing human population. A range of studies, typically focused on individual fires, have observed mobilization of contaminants, nutrients

Distinguishing intrinsic from extrinsic factors underlying firing rate saturation in human motor units

PubMed Central

Lester, Rosemary A.; Johns, Richard K.

2014-01-01

During voluntary contraction, firing rates of individual motor units (MUs) increase modestly over a narrow force range beyond which little additional increase in firing rate is seen. Such saturation of MU discharge may be a consequence of extrinsic factors that limit net synaptic excitation acting on motor neurons (MNs) or may be due to intrinsic properties of the MNs. Two sets of experiments involving recording of human biceps brachii MUs were carried out to evaluate saturation. In the first set, the extent of saturation was quantified for 136 low-threshold MUs during isometric ramp contractions. Firing rate-force data were best fit by a saturating function for 90% of MUs recorded with a maximum rate of 14.8 ± 2.0 impulses/s. In the second set of experiments, to distinguish extrinsic from intrinsic factors underlying saturation, we artificially augmented descending excitatory drive to biceps MNs by activation of muscle spindle afferents through tendon vibration. We examined the change in firing rate caused by tendon vibration in 96 MUs that were voluntarily activated at rates below and at saturation. Vibration had little effect on the discharge of MUs that were firing at saturation frequencies but strongly increased firing rates of the same units when active at lower frequencies. These results indicate that saturation is likely caused by intrinsic mechanisms that prevent further increases in firing rate in the presence of increasing synaptic excitation. Possible intrinsic cellular mechanisms that limit firing rates of motor units during voluntary effort are discussed. PMID:25475356

ChemCam Mast Unit Being Prepared for Laser Firing

NASA Image and Video Library

2010-12-23

Researchers prepare for a test of the Chemistry and Camera ChemCam instrument that will fly on NASA Mars Science Laboratory mission; researchers are preparing the instrument mast unit for a laser firing test.

Vastus Lateralis Motor Unit Firing Rate Is Higher in Women With Patellofemoral Pain.

PubMed

Gallina, Alessio; Hunt, Michael A; Hodges, Paul W; Garland, S Jayne

2018-05-01

To compare neural drive, determined from motor unit firing rate, in the vastus medialis and lateralis in women with and without patellofemoral pain. Cross-sectional study. University research laboratory. Women (N=56) 19 to 35 years of age, including 36 with patellofemoral pain and 20 controls. Not applicable. Participants sustained an isometric knee extension contraction at 10% of their maximal voluntary effort for 70 seconds. Motor units (N=414) were identified using high-density surface electromyography. Average firing rate was calculated between 5 and 35 seconds after recruitment for each motor unit. Initial firing rate was the inverse of the first 3 motor unit interspike intervals. In control participants, vastus medialis motor units discharged at higher rates than vastus lateralis motor units (P=.001). This was not observed in women with patellofemoral pain (P=.78) because of a higher discharge rate of vastus lateralis compared with control participants (P=.002). No between-group differences were observed for vastus medialis (P=.93). Similar results were obtained for the initial motor unit firing rate. These findings suggest that women with patellofemoral pain have a higher neural drive to vastus lateralis but not vastus medialis, which may be a contributor of the altered patellar kinematics observed in some studies. The different neural drive may be an adaptation to patellofemoral pain, possibly to compensate for decreased quadriceps force production, or a precursor of patellofemoral pain. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Examination of Poststroke Alteration in Motor Unit Firing Behavior Using High-Density Surface EMG Decomposition.

PubMed

Li, Xiaoyan; Holobar, Ales; Gazzoni, Marco; Merletti, Roberto; Rymer, William Zev; Zhou, Ping

2015-05-01

Recent advances in high-density surface electromyogram (EMG) decomposition have made it a feasible task to discriminate single motor unit activity from surface EMG interference patterns, thus providing a noninvasive approach for examination of motor unit control properties. In the current study, we applied high-density surface EMG recording and decomposition techniques to assess motor unit firing behavior alterations poststroke. Surface EMG signals were collected using a 64-channel 2-D electrode array from the paretic and contralateral first dorsal interosseous (FDI) muscles of nine hemiparetic stroke subjects at different isometric discrete contraction levels between 2 to 10 N with a 2 N increment step. Motor unit firing rates were extracted through decomposition of the high-density surface EMG signals and compared between paretic and contralateral muscles. Across the nine tested subjects, paretic FDI muscles showed decreased motor unit firing rates compared with contralateral muscles at different contraction levels. Regression analysis indicated a linear relation between the mean motor unit firing rate and the muscle contraction level for both paretic and contralateral muscles (p < 0.001), with the former demonstrating a lower increment rate (0.32 pulses per second (pps)/N) compared with the latter (0.67 pps/N). The coefficient of variation (averaged over the contraction levels) of the motor unit firing rates for the paretic muscles (0.21 ± 0.012) was significantly higher than for the contralateral muscles (0.17 ± 0.014) (p < 0.05). This study provides direct evidence of motor unit firing behavior alterations poststroke using surface EMG, which can be an important factor contributing to hemiparetic muscle weakness.

Mountains, fire, fire suppression, and the carbon cycle in the western United States

Treesearch

David Schimel

2004-01-01

Most mountain regions in the western United States are covered by forests, which are for the most part recovering from historical harvesting and have been experiencing active fire suppression over approximately the past 100 years (Tilman and others 2000). Whereas many western landscapes are currently perceived as pristine natural systems, the Rockies, Sierra Nevada,...

Ia Afferent input alters the recruitment thresholds and firing rates of single human motor units.

PubMed

Grande, G; Cafarelli, E

2003-06-01

Vibration of the patellar tendon recruits motor units in the knee extensors via excitation of muscle spindles and subsequent Ia afferent input to the alpha-motoneuron pool. Our first purpose was to determine if the recruitment threshold and firing rate of the same motor unit differed when recruited involuntarily via reflex or voluntarily via descending spinal pathways. Although Ia input is excitatory to the alpha-motoneuron pool, it has also been shown paradoxically to inhibit itself. Our second purpose was to determine if vibration of the patellar tendon during a voluntary knee extension causes a change in the firing rate of already recruited motor units. In the first protocol, 10 subjects voluntarily reproduced the same isometric force profile of the knee extensors that was elicited by vibration of the patellar tendon. Single motor unit recordings from the vastus lateralis (VL) were obtained with tungsten microelectrodes and unitary behaviour was examined during both reflex and voluntary knee extensions. Recordings from 135 single motor units showed that both recruitment thresholds and firing rates were lower during reflex contractions. In the second protocol, 7 subjects maintained a voluntary knee extension at 30 N for approximately 40-45 s. Three bursts of patellar tendon vibration were superimposed at regular intervals throughout the contraction and changes in the firing rate of already recruited motor units were examined. A total of 35 motor units were recorded and each burst of superimposed vibration caused a momentary reduction in the firing rates and recruitment of additional units. Our data provide evidence that Ia input modulates the recruitment thresholds and firing rates of motor units providing more flexibility within the neuromuscular system to grade force at low levels of force production.

Influence of prolonged static stretching on motor unit firing properties.

PubMed

Ye, Xin; Beck, Travis W; Wages, Nathan P

2016-05-01

The purpose of this study was to examine the influence of a stretching intervention on motor control strategy of the biceps brachii muscle. Ten men performed twelve 100-s passive static stretches of the biceps brachii. Before and after the intervention, isometric strength was tested during maximal voluntary contractions (MVCs) of the elbow flexors. Subjects also performed trapezoid isometric contractions at 30% and 70% of MVC. Surface electromyographic signals from the submaximal contractions were decomposed into individual motor unit action potential trains. Linear regression analysis was used to examine the relationship between motor unit mean firing rate and recruitment threshold. The stretching intervention caused significant decreases in y-intercepts of the linear regression lines. In addition, linear slopes at both intensities remained unchanged. Despite reduced motor unit firing rates following the stretches, the motor control scheme remained unchanged. © 2016 Wiley Periodicals, Inc.

Fire history and fire-climate relationships in upper elevation forests of the southwestern United States

NASA Astrophysics Data System (ADS)

Margolis, Ellis Quinn

Fire history and fire-climate relationships of upper elevation forests of the southwestern United States are imperative for informing management decisions in the face of increased crown fire occurrence and climate change. I used dendroecological techniques to reconstruct fires and stand-replacing fire patch size in the Madrean Sky Islands and Mogollon Plateau. Reconstructed patch size (1685-1904) was compared with contemporary patch size (1996-2004). Reconstructed fires at three sites had stand-replacing patches totaling > 500 ha. No historical stand-replacing fire patches were evident in the mixed conifer/aspen forests of the Sky Islands. Maximum stand-replacing fire patch size of modern fires (1129 ha) was greater than that reconstructed from aspen (286 ha) and spruce-fir (521 ha). Undated spruce-fir patches may be evidence of larger (>2000ha) stand-replacing fire patches. To provide climatological context for fire history I used correlation and regionalization analyses to document spatial and temporal variability in climate regions, and El-Nino Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO) and the Atlantic Multi-decadal Oscillation (AMO) teleconnections using 273 tree-ring chronologies (1732-1979). Four regions were determined by common variability in annual ring width. The component score time series replicate spatial variability in 20th century droughts (e.g., 1950's) and pluvials (e.g., 1910's). Two regions were significantly correlated with instrumental SOI and AMO, and three with PDO. Sub-regions within the southwestern U.S. varied geographically between the instrumental (1900-1979) and the pre-instrumental periods (1732-1899). Mapped correlations between ENSO, PDO and AMO, and tree-ring indices illustrate detailed sub-regional variability in the teleconnections. I analyzed climate teleconnections, and fire-climate relationships of historical upper elevation fires from 16 sites in 8 mountain ranges. I tested for links between Palmer

Coal Fires in the United States: A Case Study in Government Inattention

NASA Astrophysics Data System (ADS)

McCurdy, K. M.

2006-12-01

Coal fires occur in all coal producing nations. Like most other environmental problems fires are not confined by political boundaries. Important economic coal seams in the United States are found across the Inter-montaine west, the Midwest, and Appalachia. The age of these deposits differs, as does the grade and sulfur content of the coal, the mining techniques utilized for exploitation of this resource, and the markets in which the coal is traded. Coal fires are ordinary occurrences under extraordinary conditions. Every coal bed exposed in an underground or surface mine has the potential to ignite. These fires are spread thinly over the political geography and over time, so that constituencies rarely coalesce to petition government to address the coal fire problem. Coal fires produce serious problems with long term consequences for society. They threaten mine safety, consume a non-renewable resource, and produce toxic gases with serious health effects for local populations. Additionally, as coal production in the developing world intensifies, these problems worsen. The lack of government attention to coal fires is due to the confluence of at least four independent political factors: 1) The separated powers, federated system in which decisions in the United States are made; 2) Low levels of political energy available in Congress to be expended on coal fires, measured by the magnitude of legislative majorities and seniority; 3) The mid-twentieth century model of scientific and technical information moving indirectly to legislators through the bureaucratic agencies; 4) The chronic and diffuse nature of fires across space and time.

Motor unit firing rate patterns during voluntary muscle force generation: a simulation study

NASA Astrophysics Data System (ADS)

Hu, Xiaogang; Rymer, William Z.; Suresh, Nina L.

2014-04-01

Objective. Muscle force is generated by a combination of motor unit (MU) recruitment and changes in the discharge rate of active MUs. There have been two basic MU recruitment and firing rate paradigms reported in the literature, which describe the control of the MUs during force generation. The first (termed the reverse ‘onion skin’ profile), exhibits lower firing rates for lower threshold units, with higher firing rates occurring in higher threshold units. The second (termed the ‘onion skin’ profile), exhibits an inverse arrangement, with lower threshold units reaching higher firing rates. Approach. Using a simulation of the MU activity in a hand muscle, this study examined the force generation capacity and the variability of the muscle force magnitude at different excitation levels of the MU pool under these two different MU control paradigms. We sought to determine which rate/recruitment scheme was more efficient for force generation, and which scheme gave rise to the lowest force variability. Main results. We found that the force output of both firing patterns leads to graded force output at low excitation levels, and that the force generation capacity of the two different paradigms diverged around 50% excitation. In the reverse ‘onion skin’ pattern, at 100% excitation, the force output reached up to 88% of maximum force, whereas for the ‘onion skin’ pattern, the force output only reached up to 54% of maximum force at 100% excitation. The force variability was lower at the low to moderate force levels under the ‘onion skin’ paradigm than with the reverse ‘onion skin’ firing patterns, but this effect was reversed at high force levels. Significance. This study captures the influence of MU recruitment and firing rate organization on muscle force properties, and our results suggest that the different firing organizations can be beneficial at different levels of voluntary muscle force generation and perhaps for different tasks.

Triplet firing origin in human motor units: emerging hypotheses.

PubMed

Kudina, Lydia P; Andreeva, Regina E

2016-03-01

A specific feature of motor unit (MU) firing behaviour is rhythmic trains of single discharges at low rate resulting from the prolonged motoneuronal afterhyperpolarization. However, some MUs exhibit occasional doublets with uniquely short interspike intervals (2.5-20.0 ms). Motoneuronal delayed depolarization is commonly accepted to be doublet underlying mechanism. Apart from doublets, much scarcer MU triple discharges were described, but their mechanisms are disputable. The aim of the present study was to analyse MU triplet firing origin in healthy humans. MU triple discharges occasionally arising during gentle voluntary muscle contractions were compared with those arising in axons during motor nerve stimulation. Firing pattern was analysed in 109 MUs of four muscles: the tibialis anterior, the flexor carpi ulnaris, the abductor pollicis brevis, and the abductor digiti minimi. Our findings present evidence that during voluntary contractions two kinds of MU triplet firing can be occasionally observed: "true" motoneuronal triplets (interspike intervals of 3.6-17.3 ms) with the delayed depolarization as the possible underlying mechanism and axonal triple discharges including the M-response and F-wave. The findings can be useful not only for understanding mechanisms of the very rare motoneuronal firing in healthy humans but also for estimation of pathological triplet firing origin.

Effects of fatigue on motor unit firing rate versus recruitment threshold relationships.

PubMed

Stock, Matt S; Beck, Travis W; Defreitas, Jason M

2012-01-01

The purpose of this study was to examine the influence of fatigue on the average firing rate versus recruitment threshold relationships for the vastus lateralis (VL) and vastus medialis. Nineteen subjects performed ten maximum voluntary contractions of the dominant leg extensors. Before and after this fatiguing protocol, the subjects performed a trapezoid isometric muscle action of the leg extensors, and bipolar surface electromyographic signals were detected from both muscles. These signals were then decomposed into individual motor unit action potential trains. For each subject and muscle, the relationship between average firing rate and recruitment threshold was examined using linear regression analyses. For the VL, the linear slope coefficients and y-intercepts for these relationships increased and decreased, respectively, after fatigue. For both muscles, many of the motor units decreased their firing rates. With fatigue, recruitment of higher threshold motor units resulted in an increase in slope for the VL. Copyright © 2011 Wiley Periodicals, Inc.

Four channel Laser Firing Unit using laser diodes

NASA Technical Reports Server (NTRS)

Rosner, David, Sr.; Spomer, Edwin, Sr.

1994-01-01

This paper describes the accomplishments and status of PS/EDD's (Pacific Scientific/Energy Dynamics Division) internal research and development effort to prototype and demonstrate a practical four channel laser firing unit (LFU) that uses laser diodes to initiate pyrotechnic events. The LFU individually initiates four ordnance devices using the energy from four diode lasers carried over the fiber optics. The LFU demonstrates end-to-end optical built in test (BIT) capabilities. Both Single Fiber Reflective BIT and Dual Fiber Reflective BIT approaches are discussed and reflection loss data is presented. This paper includes detailed discussions of the advantages and disadvantages of both BIT approaches, all-fire and no-fire levels, and BIT detection levels. The following topics are also addressed: electronic control and BIT circuits, fiber optic sizing and distribution, and an electromechanical shutter type safe/arm device. This paper shows the viability of laser diode initiation systems and single fiber BIT for typing military applications.

Nonfatal residential fire-related injuries treated in emergency departments--United States, 2001.

PubMed

2003-09-26

During 2000, the most recent year for which national mortality data are available, 3,907 persons died in the United States from fire-related injuries; residential fires accounted for 2,955 (76%) of these deaths. The National Fire Protection Association (NFPA) reported that approximately 396,500 residential fires occurred in 2001. Injuries from residential fires are preventable by improving awareness of the common causes of fires and by using simple interventions (e.g., properly maintained smoke alarms and fire escape plans). Surveillance of fire-related injuries can aid prevention by increasing the understanding of these injuries and by identifying at-risk populations to target for interventions and education. To characterize nonfatal residential fire-related injuries treated in U.S. hospital emergency departments (EDs) during 2001, CDC analyzed data from the National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP). This report summarizes the results of that analysis, which indicate that, in 2001, an estimated 25,717 nonfatal residential fire-related injuries were treated in U.S. hospital EDs. Fire prevention and safety interventions and education should target at-risk populations for fire-related injuries.

The relationship of motor unit size, firing rate and force.

PubMed

Conwit, R A; Stashuk, D; Tracy, B; McHugh, M; Brown, W F; Metter, E J

1999-07-01

Using a clinical electromyographic (EMG) protocol, motor units were sampled from the quadriceps femoris during isometric contractions at fixed force levels to examine how average motor unit size and firing rate relate to force generation. Mean firing rates (mFRs) and sizes (mean surface-detected motor unit action potential (mS-MUAP) area) of samples of active motor units were assessed at various force levels in 79 subjects. MS-MUAP size increased linearly with increased force generation, while mFR remained relatively constant up to 30% of a maximal force and increased appreciably only at higher force levels. A relationship was found between muscle force and mS-MUAP area (r2 = 0.67), mFR (r2 = 0.38), and the product of mS-MUAP area and mFR (mS-MUAP x mFR) (r2 = 0.70). The results support the hypothesis that motor units are recruited in an orderly manner during forceful contractions, and that in large muscles only at higher levels of contraction ( > 30% MVC) do mFRs increase appreciably. MS-MUAP and mFR can be assessed using clinical EMG techniques and they may provide a physiological basis for analyzing the role of motor units during muscle force generation.

Examination of Post-stroke Alteration in Motor Unit Firing Behavior Using High Density Surface EMG Decomposition

PubMed Central

Li, Xiaoyan; Holobar, Aleš; Gazzoni, Marco; Merletti, Roberto; Rymer, William Z.; Zhou, Ping

2014-01-01

Recent advances in high density surface electromyogram (EMG) decomposition have made it a feasible task to discriminate single motor unit activity from surface EMG interference patterns, thus providing a noninvasive approach for examination of motor unit control properties. In the current study we applied high density surface EMG recording and decomposition techniques to assess motor unit firing behavior alterations post-stroke. Surface EMG signals were collected using a 64-channel 2-dimensional electrode array from the paretic and contralateral first dorsal interosseous (FDI) muscles of nine hemiparetic stroke subjects at different isometric discrete contraction levels between 2 N to 10 N with a 2 N increment step. Motor unit firing rates were extracted through decomposition of the high density surface EMG signals, and compared between paretic and contralateral muscles. Across the nine tested subjects, paretic FDI muscles showed decreased motor unit firing rates compared with contralateral muscles at different contraction levels. Regression analysis indicated a linear relation between the mean motor unit firing rate and the muscle contraction level for both paretic and contralateral muscles (p < 0.001), with the former demonstrating a lower increment rate (0.32 pulses per second (pps)/N) compared with the latter (0.67 pps/N). The coefficient of variation (CoV, averaged over the contraction levels) of the motor unit firing rates for the paretic muscles (0.21 ± 0.012) was significantly higher than for the contralateral muscles (0.17 ± 0.014) (p < 0.05). This study provides direct evidence of motor unit firing behavior alterations post-stroke using surface EMG, which can be an important factor contributing to hemiparetic muscle weakness. PMID:25389239

Natural desulfurization in coal-fired units using Greek lignite.

PubMed

Konidaris, Dimitrios N

2010-10-01

This paper analyzes the natural desulfurization process taking place in coal-fired units using Greek lignite. The dry scrubbing capability of Greek lignite appears to be extremely high under special conditions, which can make it possible for the units to operate within the legislative limits of sulfur dioxide (SO2) emissions. According to this study on several lignite-fired power stations in northern Greece, it was found that sulfur oxide emissions depend on coal rank, sulfur content, and calorific value. On the other hand, SO2 emission is inversely proportional to the parameter gammaCO2(max), which is equal to the maximum carbon dioxide (CO2) content by volume of dry flue gas under stoichiometric combustion. The desulfurization efficiency is positively correlated to the molar ratio of decomposed calcium carbonate to sulfur and negatively correlated to the free calcium oxide content of fly ash.

Forest-fire model with natural fire resistance.

PubMed

Yoder, Mark R; Turcotte, Donald L; Rundle, John B

2011-04-01

Observations suggest that contemporary wildfire suppression practices in the United States have contributed to conditions that facilitate large, destructive fires. We introduce a forest-fire model with natural fire resistance that supports this theory. Fire resistance is defined with respect to the size and shape of clusters; the model yields power-law frequency-size distributions of model fires that are consistent with field observations in the United States, Canada, and Australia.

Continental-scale simulation of burn probabilities, flame lengths, and fire size distribution for the United States

Treesearch

Mark A. Finney; Charles W. McHugh; Isaac Grenfell; Karin L. Riley

2010-01-01

Components of a quantitative risk assessment were produced by simulation of burn probabilities and fire behavior variation for 134 fire planning units (FPUs) across the continental U.S. The system uses fire growth simulation of ignitions modeled from relationships between large fire occurrence and the fire danger index Energy Release Component (ERC). Simulations of 10,...

United States Fire Administration

MedlinePlus

... Vehicle Fire Safety flyer PDF 234 KB Publication Risk management practices This guide contains recommended approaches to manage organizational, operational and community risk. If you are a fire department leader, our ...

40 CFR Appendix D to Part 75 - Optional SO2 Emissions Data Protocol for Gas-Fired and Oil-Fired Units

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Optional SO2 Emissions Data Protocol for Gas-Fired and Oil-Fired Units D Appendix D to Part 75 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Pt. 75, App. D Appendix D to Part 75—Optional SO2 Emissions Data...

Innovative coupling of cogeneration units with fire tube boilers: thermo-fluid dynamics of the fire tubes

NASA Astrophysics Data System (ADS)

Cioccolanti, L.; Arteconi, A.; Bartolini, C. M.; Polonara, F.

2017-11-01

Nowadays the thermal energy demand in the industrial sector is usually satisfied by means of fire tube boilers while electricity is supplied from the grid. Alternatively cogeneration units could be adopted for thermal and electrical energy self-production, whilst installing boilers only as back-up units. However, even when cogeneration is profitable, it is not widespread because industries are usually unwilling to accept cogeneration plants for reliability and high investment costs issues. In this work a system aimed at overcoming the above mentioned market difficulties is proposed. It consists of an innovative coupling of a combined heat and power unit with a modified fire tube boiler. In particular, a CFD analysis was carried out by the authors in order to address the most critical aspects related with the coupling of the two systems. More precisely, the following aspects were evaluated in detail: (i) pressure losses of the exhausts going from the prime mover to the boiler due to the sudden cross-section area variations; (ii) thermal power recoverable from the exhausts in the tubes of the boiler; (iii) dependence of the system on the final users’ specification.

Evaluating fuel complexes for fire hazard mitigation planning in the southeastern United States

Treesearch

Anne G. Andreu; Dan Shea; Bernard R. Parresol; Roger D. Ottmar

2012-01-01

Fire hazard mitigation planning requires an accurate accounting of fuel complexes to predict potential fire behavior and effects of treatment alternatives. In the southeastern United States, rapid vegetation growth coupled with complex land use history and forest management options requires a dynamic approach to fuel characterization. In this study we assessed...

High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise.

PubMed

Macgregor, Lewis J; Hunter, Angus M

2018-01-01

Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Fourteen healthy active males completed a bout of eccentric exercise on the knee extensors, with measurements of MVC, rate of torque development and surface electromyography performed pre-exercise and 2, 3, 7 and 14 days post-exercise, on both damaged and control limb. EIMD was associated with decreased MVC (235.2 ± 49.3 Nm vs. 161.3 ± 52.5 Nm; p <0.001) and rate of torque development (495.7 ± 136.9 Nm.s-1 vs. 163.4 ± 163.7 Nm.s-1; p <0.001) 48h post-exercise. Mean motor unit firing rate was reduced (16.4 ± 2.2 Hz vs. 12.6 ± 1.7 Hz; p <0.01) in high-threshold motor units only, 48h post-exercise, and common drive was elevated (0.36 ± 0.027 vs. 0.56 ± 0.032; p< 0.001) 48h post-exercise. The firing rate of high-threshold motor units was reduced in parallel with impaired muscle function, whilst early recruited motor units remained unaltered. Common drive of motor units increased in offset to the firing rate impairment. These alterations correlated with the recovery of force decrement, but not of pain elevation. This study provides fresh insight into the central mechanisms associated with EIMD recovery, relative to muscle function. These findings may in turn lead to development of novel management and preventative procedures.

High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise

PubMed Central

Macgregor, Lewis J.

2018-01-01

Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Fourteen healthy active males completed a bout of eccentric exercise on the knee extensors, with measurements of MVC, rate of torque development and surface electromyography performed pre-exercise and 2, 3, 7 and 14 days post-exercise, on both damaged and control limb. EIMD was associated with decreased MVC (235.2 ± 49.3 Nm vs. 161.3 ± 52.5 Nm; p <0.001) and rate of torque development (495.7 ± 136.9 Nm.s-1 vs. 163.4 ± 163.7 Nm.s-1; p <0.001) 48h post-exercise. Mean motor unit firing rate was reduced (16.4 ± 2.2 Hz vs. 12.6 ± 1.7 Hz; p <0.01) in high-threshold motor units only, 48h post-exercise, and common drive was elevated (0.36 ± 0.027 vs. 0.56 ± 0.032; p< 0.001) 48h post-exercise. The firing rate of high-threshold motor units was reduced in parallel with impaired muscle function, whilst early recruited motor units remained unaltered. Common drive of motor units increased in offset to the firing rate impairment. These alterations correlated with the recovery of force decrement, but not of pain elevation. This study provides fresh insight into the central mechanisms associated with EIMD recovery, relative to muscle function. These findings may in turn lead to development of novel management and preventative procedures. PMID:29630622

Effects of fire and post-fire salvage logging on avian communities in conifer-dominated forests of the western United States

USGS Publications Warehouse

Kotliar, N.B.; Hejl, S.J.; Hutto, R.L.; Saab, V.; Melcher, Cynthia; McFadzen, M.E.; George, T.L.; Dobkin, D.S.

2002-01-01

Historically, fire was one of the most widespread natural disturbances in the western United States. More recently, however, significant anthropogenic activities, especially fire suppression and silvicultural practices, have altered fire regimes; as a result, landscapes and associated communities have changed as well. Herein, we review current knowledge of how fire and postfire salvaging practices affect avian communities in conifer-dominated forests of the western United States. Specifically, we contrast avian communities in (1) burned vs. unburned forest, and (2) unsalvaged vs. salvage-logged burns. We also examine how variation in burn characteristics (e.g., severity, age, size) and salvage logging can alter avian communities in burns.Of the 41 avian species observed in three or more studies comparing early postfire and adjacent unburned forests, 22% are consistently more abundant in burned forests, 34% are usually more abundant in unburned forests, and 44% are equally abundant in burned and unburned forests or have varied responses. In general, woodpeckers and aerial foragers are more abundant in burned forest, whereas most foliage-gleaning species are more abundant in unburned forests. Bird species that are frequently observed in stand-replacement burns are less common in understory burns; similarly, species commonly observed in unburned forests often decrease in abundance with increasing burn severity. Granivores and species common in open-canopy forests exhibit less consistency among studies. For all species, responses to tire may be influenced by a number of factors including burn severity, fire size and shape, proximity to unburned forests, pre-and post-fire cover types, and time since fire. In addition, postfire management can alter species’ responses to burns. Most cavity-nesting species do not use severely salvaged burns, whereas some cavity-nesters persist in partially salvaged burns. Early post fire specialists, in particular, appear to prefer

Factors in United States Forest Service district rangers' decision to manage a fire for resource benefit

Treesearch

Martha A. Williamson

2007-01-01

United States wildland fire policy and program reviews in 1995 and 2000 required both the reduction of hazardous fuel and recognition of fire as a natural process. Despite the fact that existing policy permits managing natural ignitions to meet resource benefits, or Wildland Fire Use (WFU), most fuel reduction projects rely on mechanical treatments and prescribed fire...

Mid-21st-century climate changes increase predicted fire occurrence and fire season length, Northern Rocky Mountains, United States

USGS Publications Warehouse

Riley, Karin L.; Loehman, Rachel A.

2016-01-01

Climate changes are expected to increase fire frequency, fire season length, and cumulative area burned in the western United States. We focus on the potential impact of mid-21st-century climate changes on annual burn probability, fire season length, and large fire characteristics including number and size for a study area in the Northern Rocky Mountains. Although large fires are rare they account for most of the area burned in western North America, burn under extreme weather conditions, and exhibit behaviors that preclude methods of direct control. Allocation of resources, development of management plans, and assessment of fire effects on ecosystems all require an understanding of when and where fires are likely to burn, particularly under altered climate regimes that may increase large fire occurrence. We used the large fire simulation model FSim to model ignition, growth, and containment of wildfires under two climate scenarios: contemporary (based on instrumental weather) and mid-century (based on an ensemble average of global climate models driven by the A1B SRES emissions scenario). Modeled changes in fire patterns include increased annual burn probability, particularly in areas of the study region with relatively short contemporary fire return intervals; increased individual fire size and annual area burned; and fewer years without large fires. High fire danger days, represented by threshold values of Energy Release Component (ERC), are projected to increase in number, especially in spring and fall, lengthening the climatic fire season. For fire managers, ERC is an indicator of fire intensity potential and fire economics, with higher ERC thresholds often associated with larger, more expensive fires. Longer periods of elevated ERC may significantly increase the cost and complexity of fire management activities, requiring new strategies to maintain desired ecological conditions and limit fire risk. Increased fire activity (within the historical range of

Forest structure and fire hazard in dry forests of the Western United States

Treesearch

David L. Peterson; Morris C. Johnson; James K. Agee; Theresa B. Jain; Donald McKenzie; Elizabeth D. Reinhardt

2005-01-01

Fire, in conjunction with landforms and climate, shapes the structure and function of forests throughout the Western United States, where millions of acres of forest lands contain accumulations of flammable fuel that are much higher than historical conditions owing to various forms of fire exclusion. The Healthy Forests Restoration Act mandates that public land...

Modeling very large-fire occurrences over the continental United States from weather and climate forcing

Treesearch

R Barbero; J T Abatzoglou; E A Steel

2014-01-01

Very large-fires (VLFs) have widespread impacts on ecosystems, air quality, fire suppression resources, and in many regions account for a majority of total area burned. Empirical generalized linear models of the largest fires (>5000 ha) across the contiguous United States (US) were developed at ¡­60 km spatial and weekly temporal resolutions using solely atmospheric...

United States Geological Survey fire science: fire danger monitoring and forecasting

USGS Publications Warehouse

Eidenshink, Jeff C.; Howard, Stephen M.

2012-01-01

Each day, the U.S. Geological Survey produces 7-day forecasts for all Federal lands of the distributions of number of ignitions, number of fires above a given size, and conditional probabilities of fires growing larger than a specified size. The large fire probability map is an estimate of the likelihood that ignitions will become large fires. The large fire forecast map is a probability estimate of the number of fires on federal lands exceeding 100 acres in the forthcoming week. The ignition forecast map is a probability estimate of the number of fires on Federal land greater than 1 acre in the forthcoming week. The extreme event forecast is the probability estimate of the number of fires on Federal land that may exceed 5,000 acres in the forthcoming week.

7. INTERIOR, MAIN GARAGE, SOUTHERN WALL, FROM CLOSE TO WALL, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. INTERIOR, MAIN GARAGE, SOUTHERN WALL, FROM CLOSE TO WALL, LOOKING SOUTH, SHOWING 'GAMEWELL' FIRE ALARM TAPE CONTROL SYSTEM (TECHNOLOGY CIRCA 1910) AT CENTER, AND ENTRY TO OFFICE AT FAR RIGHT. - Oakland Naval Supply Center, Firehouse, East of Fourth Street, between A & B Streets, Oakland, Alameda County, CA

Characterizing large airtanker use in United States fire management

Treesearch

Crystal S. Stonesifer; Matthew P. Thompson; Dave Calkin; Charles W. McHugh

2015-01-01

The appropriate role of large airtankers (LATs) in federal fire suppression in the United States has been the source of much debate and discussion in recent years as the U.S. Forest Service (USFS) has faced impending decisions about how best to address an aging fleet of contracted aircraft. Questions of fleet efficiency are complicated by inadequacies in historical...

Muscle vibration sustains motor unit firing rate during submaximal isometric fatigue in humans

PubMed Central

Griffin, L; Garland, S J; Ivanova, T; Gossen, E R

2001-01-01

In keeping with the ‘muscular wisdom hypothesis’, many studies have documented that the firing rate of the majority of motor units decreased during fatiguing isometric contractions. The present study investigated whether the application of periodic muscle vibration, which strongly activates muscle spindles, would alter the modulation of motor unit firing rate during submaximal fatiguing isometric contractions. Thirty-three motor units from the lateral head of the triceps brachii muscle were recorded from 10 subjects during a sustained isometric 20 % maximal voluntary contraction (MVC) of the elbow extensors. Vibration was interposed on the contraction for 2 s every 10 s. Twenty-two motor units were recorded from the beginning of the fatigue task. The discharge rate of the majority of motor units remained constant (12/22) or increased (4/22) with fatigue. Six motor units demonstrated a reduction in discharge rate that later returned toward initial values; these motor units had higher initial discharge rates than the other 16 motor units. In a second series of experiments, four subjects held a sustained isometric 20 % MVC for 2 min and then vibration was applied as above for the remainder of the contraction. In this case, motor units initially demonstrated a decrease in firing rate that increased after the vibration was applied. Thus muscle spindle disfacilitation of the motoneurone pool may be associated with the decline of motor unit discharge rate observed during the first 2 min of the contraction. In a third set of experiments, seven subjects performed the main experiment on one occasion and repeated the fatigue task without vibration on a second occasion. Neither the endurance time of the fatiguing contraction nor the MVC torque following fatigue was affected by the application of vibration. This finding calls into question the applicability of the muscular wisdom hypothesis to submaximal contractions. PMID:11559785

Muscle vibration sustains motor unit firing rate during submaximal isometric fatigue in humans.

PubMed

Griffin, L; Garland, S J; Ivanova, T; Gossen, E R

2001-09-15

1. In keeping with the 'muscular wisdom hypothesis', many studies have documented that the firing rate of the majority of motor units decreased during fatiguing isometric contractions. The present study investigated whether the application of periodic muscle vibration, which strongly activates muscle spindles, would alter the modulation of motor unit firing rate during submaximal fatiguing isometric contractions. 2. Thirty-three motor units from the lateral head of the triceps brachii muscle were recorded from 10 subjects during a sustained isometric 20 % maximal voluntary contraction (MVC) of the elbow extensors. Vibration was interposed on the contraction for 2 s every 10 s. Twenty-two motor units were recorded from the beginning of the fatigue task. The discharge rate of the majority of motor units remained constant (12/22) or increased (4/22) with fatigue. Six motor units demonstrated a reduction in discharge rate that later returned toward initial values; these motor units had higher initial discharge rates than the other 16 motor units. 3. In a second series of experiments, four subjects held a sustained isometric 20 % MVC for 2 min and then vibration was applied as above for the remainder of the contraction. In this case, motor units initially demonstrated a decrease in firing rate that increased after the vibration was applied. Thus muscle spindle disfacilitation of the motoneurone pool may be associated with the decline of motor unit discharge rate observed during the first 2 min of the contraction. 4. In a third set of experiments, seven subjects performed the main experiment on one occasion and repeated the fatigue task without vibration on a second occasion. Neither the endurance time of the fatiguing contraction nor the MVC torque following fatigue was affected by the application of vibration. This finding calls into question the applicability of the muscular wisdom hypothesis to submaximal contractions.

Impact of red imported fire ant infestation on northern bobwhite quail abundance trends in southeastern United States

USGS Publications Warehouse

Allen, Craig R.; Willey, R.D.; Myers, P.E.; Horton, P.M.; Buffa, J.

2000-01-01

Northern bobwhite quail (Colinus virginianus L.) populations are declining throughout their range. One factor contributing to the decline in the southeastern United States may be the red imported fire ant (Solenopsis invicta Buren). Recent research in Texas has documented that red imported fire ants can have a significant impact on northern bobwhite quail. That research was conducted in areas where fire ants are predominately polygynous (multiple queen). Polygynous infestations have much higher mound densities than the monogynous (single queen) form. In most of the southeastern United States, fire ants are predominately monogynous. We determined if there was a relationship between the invasion of monogynous red imported fire ants and abundance trends in northern bobwhite quail in the southeastern United States. For Florida, Georgia, and South Carolina we compared average northern bobwhite quail abundance based on Christmas Bird Count data for each county before and after fire ant invasion, and conducted regression analyses on bobwhite quail abundance and year preinvasion, and abundance and year postinvasion. Regionally, northern bobwhite quail were more abundant before (0.067 ??0.018 bobwhite quail per observer hour) than after fire ants invaded (0.019 ?? 0.006; Z = -3.746, df = 18, P 30-yr variation in invasion dates.

The Research of Utilization Hours of Coal-Fired Power Generation Units Based on Electric Energy Balance

NASA Astrophysics Data System (ADS)

Liu, Junhui; Yang, Jianlian; Wang, Jiangbo; Yang, Meng; Tian, Chunzheng; He, Xinhui

2018-01-01

With grid-connected scale of clean energy such as wind power and photovoltaic power expanding rapidly and cross-province transmission scale being bigger, utilization hours of coal-fired power generation units become lower and lower in the context of the current slowdown in electricity demand. This paper analyzes the influencing factors from the three aspects of demand, supply and supply and demand balance, and the mathematical model has been constructed based on the electric energy balance. The utilization hours of coal-fired power generation units have been solved considering the relationship among proportion of various types of power installed capacity, the output rate and utilization hours. By carrying out empirical research in Henan Province, the utilization hours of coal-fired units of Henan Province in 2020 has been achieved. The example validates the practicability and the rationality of the model, which can provide a basis for the decision-making for coal-fired power generation enterprises.

DEMONSTRATION OF SORBENT INJECTION TECHNOLOGY ON A WALL-FIRED UTILITY BOILER (EDGEWATER LIMB DEMONSTRATION)

EPA Science Inventory

The report gives results of the full-scale demonstration of Limestone Injection Multistage Burner (LIMB) technology on the coal-fired, 105 MW, Unit 4 boiler at Ohio Edison's Edgewater Station. eveloped as a technology aimed at moderate levels of sulfur dioxide (SO2) and nitrogen ...

A growing importance of large fires in conterminous United States during 1984-2012

Treesearch

Jia Yang; Hanqin Tian; Bo Tao; Wei Ren; Shufen Pan; Yongqiang Liu; Yuhang Wang

2015-01-01

Fire frequency, extent, and size exhibit a strong linkage with climate conditions and play a vital role in the climate system. Previous studies have shown that the frequency of large fires in the western United States increased significantly since the mid-1980s due to climate warming and frequent droughts. However, less work has been conducted to examine burned area...

An Evaluation of Historical Fire Occurrence, Drought and the El Niño Southern Oscillation in the Southcentral United States

NASA Astrophysics Data System (ADS)

Rooney, M.; Stambaugh, M. C.

2016-12-01

Wildfire occurrence in the forested ecosystems of the southcentral United States is driven by conditions of drought. Historically, fire intervals varied temporally and spatially - forced by climate, humans, and environmental conditions. Thus, proxy records are required to assess the relationships between fire occurrence, drought, and the El Niño Southern Oscillation (ENSO). Fire scar data from tree-rings are well-suited to assess historical fire regimes in this region, paired with reconstructions of drought and ENSO that have been developed from networks of ring-width chronologies across the United States. This study combines fire-scar data from twelve different sites in the southcentral United States, including two new fire-history reconstructions. Fire data incorporates 665 fires across Eastern Oklahoma and Northern Texas from 1637-2014. These robust reconstructions of post oak (Quercus stellata) evaluate the variability in fire activity and its association to drought and ENSO. Climate-explained growth variance in post-oak chronologies is strong in this region, providing powerful proxy information in the derived chronologies. In general, most fires occur during the La Niña portion of the ENSO cycle. Many severe fires correspond with drought, and results from super-posed epoch analysis suggest a significant relationship between fire event years and drought conditions in the full period of record. Analysis reveals differences in the relationships of fire, drought and ENSO through time, corresponding to changes in human settlement in the region. Understanding the spatial and temporal relationships that exist between fire occurrence, drought, and ENSO aid in quantifying disturbance characteristics and their associations to climate in the forested ecosystems of the southcentral United States.

Proceedings of the 2002 fire conference: managing fire and fuels in the remaining wildlands and open spaces of the Southwestern United States

Treesearch

Marcia G. Narog

2008-01-01

Many issues confront scientists, land managers, policymakers, and the public who deal with or are affected by management of fire and fuels across the southwestern United States (Utah, Colorado, Arizona, Nevada, New Mexico, and California). The 2002 Fire Conference was convened to tackle these concerns. It began with a plenary session addressing the central problems of...

Unit 5, nonfederal wall, 536538 Vine Street Building, & St. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 5, non-federal wall, 536-538 Vine Street Building, & St. Vincent-Depaul store building-context - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

Effects of barbell deadlift training on submaximal motor unit firing rates for the vastus lateralis and rectus femoris.

PubMed

Stock, Matt S; Thompson, Brennan J

2014-01-01

Previous investigations that have studied motor unit firing rates following strength training have been limited to small muscles, isometric training, or interventions involving exercise machines. We examined the effects of ten weeks of supervised barbell deadlift training on motor unit firing rates for the vastus lateralis and rectus femoris during a 50% maximum voluntary contraction (MVC) assessment. Twenty-four previously untrained men (mean age  = 24 years) were randomly assigned to training (n = 15) or control (n = 9) groups. Before and following the intervention, the subjects performed isometric testing of the right knee extensors while bipolar surface electromyographic signals were detected from the two muscles. The signals were decomposed into their constituent motor unit action potential trains, and motor units that demonstrated accuracy levels less than 92.0% were not considered for analysis. One thousand eight hundred ninety-two and 2,013 motor units were examined for the vastus lateralis and rectus femoris, respectively. Regression analyses were used to determine the linear slope coefficients (pulses per second [pps]/% MVC) and y-intercepts (pps) of the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. Deadlift training significantly improved knee extensor MVC force (Cohen's d = .70), but did not influence force steadiness. Training had no influence on the slopes and y-intercepts for the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. In agreement with previous cross-sectional comparisons and randomized control trials, our findings do not support the notion that strength training affects the submaximal control of motor units.

Effects of Barbell Deadlift Training on Submaximal Motor Unit Firing Rates for the Vastus Lateralis and Rectus Femoris

PubMed Central

Stock, Matt S.; Thompson, Brennan J.

2014-01-01

Previous investigations that have studied motor unit firing rates following strength training have been limited to small muscles, isometric training, or interventions involving exercise machines. We examined the effects of ten weeks of supervised barbell deadlift training on motor unit firing rates for the vastus lateralis and rectus femoris during a 50% maximum voluntary contraction (MVC) assessment. Twenty-four previously untrained men (mean age  = 24 years) were randomly assigned to training (n = 15) or control (n = 9) groups. Before and following the intervention, the subjects performed isometric testing of the right knee extensors while bipolar surface electromyographic signals were detected from the two muscles. The signals were decomposed into their constituent motor unit action potential trains, and motor units that demonstrated accuracy levels less than 92.0% were not considered for analysis. One thousand eight hundred ninety-two and 2,013 motor units were examined for the vastus lateralis and rectus femoris, respectively. Regression analyses were used to determine the linear slope coefficients (pulses per second [pps]/% MVC) and y-intercepts (pps) of the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. Deadlift training significantly improved knee extensor MVC force (Cohen's d = .70), but did not influence force steadiness. Training had no influence on the slopes and y-intercepts for the mean firing rate and firing rate at recruitment versus recruitment threshold relationships. In agreement with previous cross-sectional comparisons and randomized control trials, our findings do not support the notion that strength training affects the submaximal control of motor units. PMID:25531294

Reduced firing rates of high threshold motor units in response to eccentric overload.

PubMed

Balshaw, Tom G; Pahar, Madhu; Chesham, Ross; Macgregor, Lewis J; Hunter, Angus M

2017-01-01

Acute responses of motor units were investigated during submaximal voluntary isometric tasks following eccentric overload (EO) and constant load (CL) knee extension resistance exercise. Ten healthy resistance-trained participants performed four experimental test sessions separated by 5 days over a 20 day period. Two sessions involved constant load and the other two used eccentric overload. EO and CL used both sessions for different target knee eccentric extension phases; one at 2 sec and the other at 4 sec. Maximal voluntary contractions (MVC) and isometric trapezoid efforts for 10 sec at 70% MVC were completed before and after each intervention and decomposed electromyography was used to measure motor unit firing rate. The firing rate of later recruited, high-threshold motor units declined following the 2-sec EO but was maintained following 2sec CL (P < 0.05), whereas MUFR for all motor units were maintained for both loading types following 4-sec extension phases. MVC and rate of force development where maintained following both EO and CL and 2 and 4 sec phases. This study demonstrates a slower firing rate of high-threshold motor units following fast eccentric overload while MVC was maintained. This suggests that there was a neuromuscular stimulus without cost to the force-generating capacity of the knee extensors. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

A review of the relationships between drought and forest fire in the United States

USGS Publications Warehouse

Littell, Jeremy; Peterson, David L.; Riley, Karin L.; Yongquiang Liu,; Luce, Charles H.

2016-01-01

The historical and pre-settlement relationships between drought and wildfire are well documented in North America, with forest fire occurrence and area clearly increasing in response to drought. There is also evidence that drought interacts with other controls (forest productivity, topography, fire weather, management activities) to affect fire intensity, severity, extent, and frequency. Fire regime characteristics arise across many individual fires at a variety of spatial and temporal scales, so both weather and climate—including short- and long-term droughts—are important and influence several, but not all, aspects of fire regimes. We review relationships between drought and fire regimes in United States forests, fire-related drought metrics and expected changes in fire risk, and implications for fire management under climate change. Collectively, this points to a conceptual model of fire on real landscapes: fire regimes, and how they change through time, are products of fuels and how other factors affect their availability (abundance, arrangement, continuity) and flammability (moisture, chemical composition). Climate, management, and land use all affect availability, flammability, and probability of ignition differently in different parts of North America. From a fire ecology perspective, the concept of drought varies with scale, application, scientific or management objective, and ecosystem.

MUNICIPAL WASTE COMBUSTION ASSESSMENT: FOSSIL FUEL CO-FIRING

EPA Science Inventory

The report identifies refuse derived fuel (RDF) processing operations and various RDF types; describes such fossil fuel co-firing techniques as coal fired spreader stokers, pulverized coal wall fired boilers, pulverized coal tangentially fired boilers, and cyclone fired boilers; ...

Motor unit firing rates and synchronisation affect the fractal dimension of simulated surface electromyogram during isometric/isotonic contraction of vastus lateralis muscle.

PubMed

Mesin, Luca; Dardanello, Davide; Rainoldi, Alberto; Boccia, Gennaro

2016-12-01

During fatiguing contractions, many adjustments in motor units behaviour occur: decrease in muscle fibre conduction velocity; increase in motor units synchronisation; modulation of motor units firing rate; increase in variability of motor units inter-spike interval. We simulated the influence of all these adjustments on synthetic EMG signals in isometric/isotonic conditions. The fractal dimension of the EMG signal was found mainly influenced by motor units firing behaviour, being affected by both firing rate and synchronisation level, and least affected by muscle fibre conduction velocity. None of the calculated EMG indices was able to discriminate between firing rate and motor units synchronisation. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Evaluating potential changes in fire risk from Eucalyptus plantings in the Southern United States

Treesearch

Scott L. Goodrick; John A. Stanturf

2012-01-01

Renewed interest in short-rotation woody crops for bioenergy and bioproducts has prompted a reevaluation of the Eucalyptus species for the southern United States. One question that arises about the potential effects of introducing a nonnative species is what effect will there be on fire behavior. Our approximate answer based on modeling fire behavior...

The potential impact of regional climate change on fire weather in the United States

Treesearch

Ying Tang; Shiyuan Zhong; Lifeng Luo; Xindi Bian; Warren E. Heilman; Julie. Winkler

2015-01-01

Climate change is expected to alter the frequency and severity of atmospheric conditions conducive for wildfires. In this study, we assess potential changes in fire weather conditions for the contiguous United States using the Haines Index (HI), a fire weather index that has been employed operationally to detect atmospheric conditions favorable for large and erratic...

Spatiotemporal patterns of unburned areas within fire perimeters in the northwestern United States from 1984 to 2014

Treesearch

Arjan J. H. Meddens; Crystal A. Kolden; James A. Lutz; John T. Abatzoglou; Andrew T. Hudak

2018-01-01

A warming climate, fire exclusion, and land cover changes are altering the conditions that produced historical fire regimes and facilitating increased recent wildfire activity in the northwestern United States. Understanding the impacts of changing fire regimes on forest recruitment and succession, species distributions, carbon cycling, and ecosystem services is...

Experimental studies of microwave propagation through fires for through-wall, search-and-rescue radar in firefighting

NASA Astrophysics Data System (ADS)

Temme, Andrew Kenneth Gerken

Finding people trapped inside of a burning house is extremely difficult, dangerous, and time consuming. Smoke, heat, unfamiliar floor plans, and possible structural collapse all combine to challenge a firefighter's ability to find a person. Thermal imaging cameras, the most advanced technology available to firefighters today, are able to see through smoke but are unable to see through walls and household items. Through-wall radar and vital-sign detection radar offer an imaging modality that may be able to help firefighters find victims from outside of a room or even a house. Flames can interact with electromagnetic (radar) waves because the flames create a weakly-ionized plasma. Previous work has looked at small flames fueled by pure gases or flames from wildfires. Combustable items in a house are typically petroleum-based products that have different combustion reactions compared to previously studied flames and fire-induced plasmas. Because of this, it is unknown how electromagnetic waves interact with flames found in a house fire. This dissertation investigates the question of how electromagnetic waves interact with flames in a house fire. This is an open problem, with many variables, that poses a subtle and difficult measurement task. This work focuses on creating experimental techniques to explore this problem. From an electromagnetic metrology perspective, the physical phenomena of interest are difficult to measure due to ill-defined physical boundaries, characteristics lengths of varying magnitude, inhomogeneity, and varying time scales. The experimental methods studied here primarily focus on transmission measurements through flames a few feet in height. Additionally, this work presents a proof-of-concept two-wire transmission line for bench-scale, material-characterization of solids, liquids, gases, and flames. Results from this work provide a metrological foundation for future studies in this area. An experimental setup that can withstand direct exposure

Firefighters United for Safety, Ethics, and Ecology (FUSEE): Torchbearers for a new fire management paradigm

Treesearch

Timothy Ingalsbee; Joseph Fox; Patrick Withen

2007-01-01

Firefighters United for Safety, Ethics, and Ecology (FUSEE) is a nonprofit organization promoting safe, ethical, ecological wildland fire management. FUSEE believes firefighter and community safety are ultimately interdependent with ethical public service, wildlands protection, and ecological restoration of fire-adapted ecosystems. Our members include current, former,...

A review of the relationships between drought and forest fire in the United States.

PubMed

Littell, Jeremy S; Peterson, David L; Riley, Karin L; Liu, Yongquiang; Luce, Charles H

2016-07-01

The historical and presettlement relationships between drought and wildfire are well documented in North America, with forest fire occurrence and area clearly increasing in response to drought. There is also evidence that drought interacts with other controls (forest productivity, topography, fire weather, management activities) to affect fire intensity, severity, extent, and frequency. Fire regime characteristics arise across many individual fires at a variety of spatial and temporal scales, so both weather and climate - including short- and long-term droughts - are important and influence several, but not all, aspects of fire regimes. We review relationships between drought and fire regimes in United States forests, fire-related drought metrics and expected changes in fire risk, and implications for fire management under climate change. Collectively, this points to a conceptual model of fire on real landscapes: fire regimes, and how they change through time, are products of fuels and how other factors affect their availability (abundance, arrangement, continuity) and flammability (moisture, chemical composition). Climate, management, and land use all affect availability, flammability, and probability of ignition differently in different parts of North America. From a fire ecology perspective, the concept of drought varies with scale, application, scientific or management objective, and ecosystem. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Fire containment in wood construction doesn’t just happen

Treesearch

Robert H. White; Kuma Sumathipala

2007-01-01

Regardless of the type of construction, structures capable of containing a fully developed fire do not just happen. Fire walls or area separation walls play an important role in the building codes in that they allow each portion of a building separated by such walls to be treated as a separate building. Attention to construction details is critical to maximizing the...

5. UNIT VENTILATOR, MEN'S BATH HALL, SHOWING POSITION AGAINST WALL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. UNIT VENTILATOR, MEN'S BATH HALL, SHOWING POSITION AGAINST WALL ABOVE THE BATHS. - Hot Springs National Park, Bathhouse Row, Ozark Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

Climate-Driven Risk of Large Fire Occurrence in the Western United States, 1500 to 2003

NASA Astrophysics Data System (ADS)

Crockett, J.; Westerling, A. L.

2017-12-01

Spatially comprehensive fire climatology has provided managers with tools to understand thecauses and consequences of large forest wildfires, but a paleoclimate context is necessary foranticipating the trajectory of future climate-fire relationships. Although accumulated charcoalrecords and tree scars have been utilized in high resolution, regional fire reconstructions, there isuncertainty as to how current climate-fire relationships of the western United States (WUS) fitwithin the natural long-term variability. While contemporary PDSI falls within the naturalvariability of the past, contemporary temperatures skew higher. Here, we develop a WUSfire reconstruction by applying climate-fire-topography model built on the 1972 to 2003 periodto the past 500 years, validated by recently updated fire-scar histories from WUS forests. Theresultant narrative provides insight into changing climate-fire relationships during extendedperiods of high aridity and temperature, providing land managers with historical precedent toeffectively anticipate disturbances during future climate change.

Wildfire risk reduction in the United States: Leadership staff perceptions of local fire department roles and responsibilities

Treesearch

Rachel S. Madsen; Hylton J. G. Haynes; Sarah M. McCaffrey

2018-01-01

As wildland fires have had increasing negative impacts on a range of human values, in many parts of the United States (U.S.) and around the world, collaborative risk reduction efforts among agencies, homeowners, and fire departments are needed to improve wildfire safety and mitigate risk. Using interview data from 46 senior officers from local fire departments around...

Potential climate change impacts on fire weather in the United States

Treesearch

Warren E. Heilman; Ying Tang; Lifeng Luo; Shiyuan Zhong; Julie Winkler; Xindi. Bian

2015-01-01

Researchers at Michigan State University and the Forest Service's Northern Research Station worked on a joint study to examine the possible effects of future global and regional climate change on the occurrence of fire-weather patterns often associated with extreme and erratic wildfire behavior in the United States.

Implementation of National Fire Plan treatments near the wildland-urban interface in the western United States.

PubMed

Schoennagel, Tania; Nelson, Cara R; Theobald, David M; Carnwath, Gunnar C; Chapman, Teresa B

2009-06-30

Because of increasing concern about the effects of catastrophic wildland fires throughout the western United States, federal land managers have been engaged in efforts to restore historical fire behavior and mitigate wildfire risk. During the last 5 years (2004-2008), 44,000 fuels treatments were implemented across the western United States under the National Fire Plan (NFP). We assessed the extent to which these treatments were conducted in and near the wildland-urban interface (WUI), where they would have the greatest potential to reduce fire risk in neighboring homes and communities. Although federal policies stipulate that significant resources should be invested in the WUI, we found that only 3% of the area treated was within the WUI, and another 8% was in an additional 2.5-km buffer around the WUI, totaling 11%. Only 17% of this buffered WUI is under federal ownership, which significantly limits the ability of federal agencies to implement fire-risk reduction treatments near communities. Although treatments far from the WUI may have some fire mitigation benefits, our findings suggest that greater priority must be given to locating treatments in and near the WUI, rather than in more remote settings, to satisfy NFP goals of reducing fire risk to communities. However, this may require shifting management and policy emphasis from public to private lands.

Motor unit firing and its relation to tremor in the tonic vibration reflex of the decerebrate cat.

PubMed

Clark, F J; Matthews, P B; Muir, R B

1981-01-01

1. The discharge of single motor units has been recorded from the soleus muscle of the decerebrate cat during the tonic vibration reflex elicited isometrically, to further understanding of the tremor that is seen in the reflex contraction. The reflex was elicited by pulses of vibration of 50 micrometers amplitude at 150 Hz, and up to four units were studied concurrently. 2. Individual units fired rather regularly and at a low frequency (range 4-14 Hz). The rate of firing of any unit normally fell within the frequency band of the tremor recorded at the same time. On comparing different preparations a higher frequency of tremor was associated with a higher frequency of motor firing. 3. The responses of pairs of motor units recorded concurrently during repeated production of the reflex were compared by cross-correlation analysis; over 1000 spikes from each train were normally used for this. The major of the cross-correlograms were flat with no overt sign of any synchronization between the units other than that due to the vibration. 4. Clear indications of correlated motor unit firing could be produced deliberately by modulating the amplitude of vibration at a frequency comparable to that of the normal tremor and thereby introducing a rhythmic component into the tonic vibration reflex. 5. About 20% of the cross-correlograms obtained during normal tremor showed varying amounts of an irregular 'waviness' suggesting a possible correlation between the times of firing of a pair of units. But such waves never developed steadily throughout the period of analysis, in contrast to the comparable waves produced on modulating the vibration. Similar waves were seen on cross-correlating a motor unit with an electronic oscillator, confirming that their occurrence does not necessarily demonstrate the existence of active neural interactions. 6. It is concluded that there is no strong and widespread neural synchronizing mechanism active during the tonic vibration reflex, although the

Using NASA Satellite Observations to Map Wildfire Risk in the United States for Allocation of Fire Management Resources

NASA Astrophysics Data System (ADS)

Farahmand, A.; Reager, J. T., II; Behrangi, A.; Stavros, E. N.; Randerson, J. T.

2017-12-01

Fires are a key disturbance globally acting as a catalyst for terrestrial ecosystem change and contributing significantly to both carbon emissions and changes in surface albedo. The socioeconomic impacts of wildfire activities are also significant with wildfire activity results in billions of dollars of losses every year. Fire size, area burned and frequency are increasing, thus the likelihood of fire danger, defined by United States National Interagency Fire Center (NFIC) as the demand of fire management resources as a function of how flammable fuels (a function of ignitability, consumability and availability) are from normal, is an important step toward reducing costs associated with wildfires. Numerous studies have aimed to predict the likelihood of fire danger, but few studies use remote sensing data to map fire danger at scales commensurate with regional management decisions (e.g., deployment of resources nationally throughout fire season with seasonal and monthly prediction). Here, we use NASA Gravity Recovery And Climate Experiment (GRACE) assimilated surface soil moisture, NASA Atmospheric Infrared Sounder (AIRS) vapor pressure deficit, NASA Moderate Resolution Imaging Spectroradiometer (MODIS) enhanced vegetation index products and landcover products, along with US Forest Service historical fire activity data to generate probabilistic monthly fire potential maps in the United States. These maps can be useful in not only government operational allocation of fire management resources, but also improving understanding of the Earth System and how it is changing in order to refine predictions of fire extremes.

Distortion of three-unit implant frameworks during casting, soldering, and simulated porcelain firings.

PubMed

Zervas, P J; Papazoglou, E; Beck, F M; Carr, A B

1999-09-01

The aim of this study was to assess distortion inherent in casting, soldering, and simulated porcelain firings of screw-retained, implant-supported three-unit fixed partial dentures (FPDs). Ten wax patterns were fabricated on a die-stone cast containing two implants, 20 mm apart from center to center. Five specimens were cast in a high-palladium alloy, exposed to simulated porcelain firings, sectioned, and then soldered with low-fusing solder. Five specimens were cast, sectioned, soldered with high-fusing solder, and then exposed to simulated porcelain firings. For each specimen, two horizontal and six vertical distances between appropriately scribed reference points were measured with a traveling microscope. Comparisons were made among the various measurements taken after wax-pattern fabrication, casting, high- and low-fusing soldering, and each porcelain firing. Data were analyzed using a repeated-measures factorial ANOVA (alpha = 0.05). Significant difference was detected in the amount of horizontal distortion during casting (53 +/- 24 microns) and high-fusing soldering (-49 +/- 50 microns), as well as in the amount of horizontal distortion during high-fusing soldering (-49 +/- 50 microns) and low-fusing soldering (17 +/- 26 microns). However, no clinically significant difference was found in the amount of horizontal distortion during casting, low-fusing, and high-fusing soldering. The greatest amount of distortion during the simulated porcelain firings took place during the oxidizing cycle. Soldering did not improve the casting misfit of a three-unit implant-retained FPD model. Metal-ceramic implant frameworks should be oxidized before intraoral fit evaluation.

Fire suppression effectiveness for simultaneous fires: an examination of fire histories

Treesearch

Larry F. Bednar; Romain Mees; David Strauss

1990-01-01

We examined fire and weather records for areas of the western United States for the period 1970-1984 to determine the effects of simultaneous wildfire occurrence on fire suppression efforts. Burning conditions were accounted for by use of short strings of fires which involved simultaneous suppression efforts. These strings were matched with closely preceding isolated...

Mineralogy and stratigraphy of the Gale crater rim, wall, and floor units

NASA Astrophysics Data System (ADS)

Buz, Jennifer; Ehlmann, Bethany L.; Pan, Lu; Grotzinger, John P.

2017-05-01

The Curiosity rover has detected diverse lithologies in float rocks and sedimentary units on the Gale crater floor, interpreted to have been transported from the rim. To understand their provenance, we examine the mineralogy and geology of Gale's rim, walls, and floor, using high-resolution imagery and infrared spectra. While no significant differences in bedrock spectral properties were observed within most Thermal Emission Imaging System and Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) scenes, some CRISM scenes of rim and wall rocks showed olivine-bearing bedrock accompanied by Fe/Mg phyllosilicates. Hydrated materials with 2.48 μm absorptions in Gale's eastern walls are spectrally similar to the sulfate unit in Mount Sharp (Aeolis Mons). Sedimentary strata on the Gale floor southwest of the landing site, likely coeval with the Bradbury units explored by Curiosity, also are hydrated and/or have Fe/Mg phyllosilicates. Spectral properties of these phyllosilicates differ from the Al-substituted nontronite detected by CRISM in Mount Sharp, suggesting formation by fluids of different composition. Geologic mapping of the crater floor shows that the hydrated or hydroxylated materials are typically overlain by spectrally undistinctive, erosionally resistant, cliff-forming units. Additionally, a 4 km impact crater exposes >250 m of the Gale floor, including finely layered units. No basement rocks are exposed, thus indicating sedimentary deposits ≥250 m beneath strata studied by Curiosity. Collectively, the data indicate substantial sedimentary infill of Gale crater, including some materials derived from the crater rim. Lowermost thin layers are consistent with deposition in a lacustrine environment; interbedded hydrated/hydroxylated units may signify changing environmental conditions, perhaps in a drying or episodically dry lake bed.

A wall-free climate unit for acoustic levitators.

PubMed

Schlegel, M C; Wenzel, K-J; Sarfraz, A; Panne, U; Emmerling, F

2012-05-01

Acoustic levitation represents the physical background of trapping a sample in a standing acoustic wave with no contact to the wave generating device. For the last three decades, sample holders based on this effect have been commonly used for contact free handling of samples coupled with a number of analytical techniques. In this study, a wall-free climate unit is presented, which allows the control of the environmental conditions of suspended samples. The insulation is based on a continuous cold/hot gas flow around the sample and thus does not require any additional isolation material. This provides a direct access to the levitated sample and circumvents any influence of the climate unit material to the running analyses.

A wall-free climate unit for acoustic levitators

NASA Astrophysics Data System (ADS)

Schlegel, M. C.; Wenzel, K.-J.; Sarfraz, A.; Panne, U.; Emmerling, F.

2012-05-01

Acoustic levitation represents the physical background of trapping a sample in a standing acoustic wave with no contact to the wave generating device. For the last three decades, sample holders based on this effect have been commonly used for contact free handling of samples coupled with a number of analytical techniques. In this study, a wall-free climate unit is presented, which allows the control of the environmental conditions of suspended samples. The insulation is based on a continuous cold/hot gas flow around the sample and thus does not require any additional isolation material. This provides a direct access to the levitated sample and circumvents any influence of the climate unit material to the running analyses.

A comprehensive guide to fuel management practices for dry mixed conifer forests in the northwestern United States: Prescribed fire

Treesearch

Theresa B. Jain; Mike A. Battaglia; Han-Sup Han; Russell T. Graham; Christopher R. Keyes; Jeremy S. Fried; Jonathan E. Sandquist

2014-01-01

Fire has had a profound historical role in shaping dry mixed conifer forests in the western United States. However, the uncertainty and complexity of prescribed fires raises the question “Is fire always the best option for treating fuels?” The decision to use prescribed fire is dependent upon several factors.

Ten Fire Safety Tips for Schools.

ERIC Educational Resources Information Center

Lake, James D.

1999-01-01

Provides 10 basic tips, compiled from the National Fire Protection Association's Life Safety Code 101, to ensure that educational facilities are fire safe. Tips include use of frequent and unexpected fire drills, limiting wall space of student artwork and teaching materials, being alert to preventing arson, planning speedy and safe emergency…

Unit 4, STA. 31+ 00+ lb, sideslope with concrete walls ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 4, STA. 31+ 00+ lb, sideslope with concrete walls (without parapets), Cambria Iron Company National Historic Landmark-detail - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

Fire ants

MedlinePlus

... a fire ant delivers a harmful substance, called venom, into your skin. This article is for information ... in the United States. Poisonous Ingredient Fire ant venom contains a chemical called piperidine. Where Found Fire ...

Motor unit recruitment and firing rate in medial gastrocnemius muscles during external perturbations in standing in humans.

PubMed

Pollock, C L; Ivanova, T D; Hunt, M A; Garland, S J

2014-10-01

There is limited investigation of the interaction between motor unit recruitment and rate coding for modulating force during standing or responding to external perturbations. Fifty-seven motor units were recorded from the medial gastrocnemius muscle with intramuscular electrodes in response to external perturbations in standing. Anteriorly directed perturbations were generated by applying loads in 0.45-kg increments at the pelvis every 25-40 s until 2.25 kg was maintained. Motor unit firing rate was calculated for the initial recruitment load and all subsequent loads during two epochs: 1) dynamic response to perturbation directly following each load drop and 2) maintenance of steady state between perturbations. Joint kinematics and surface electromyography (EMG) from lower extremities and force platform measurements were assessed. Application of the external loads resulted in a significant forward progression of the anterior-posterior center of pressure (AP COP) that was accompanied by modest changes in joint angles (<3°). Surface EMG increased more in medial gastrocnemius than in the other recorded muscles. At initial recruitment, motor unit firing rate immediately after the load drop was significantly lower than during subsequent load drops or during the steady state at the same load. There was a modest increase in motor unit firing rate immediately after the load drop on subsequent load drops associated with regaining balance. There was no effect of maintaining balance with increased load and forward progression of the AP COP on steady-state motor unit firing rate. The medial gastrocnemius utilized primarily motor unit recruitment to achieve the increased levels of activation necessary to maintain standing in the presence of external loads. Copyright © 2014 the American Physiological Society.

Management and climate contributions to satellite-derived active fire trends in the contiguous United States

PubMed Central

Lin, Hsiao-Wen; McCarty, Jessica L; Wang, Dongdong; Rogers, Brendan M; Morton, Douglas C; Collatz, G James; Jin, Yufang; Randerson, James T

2014-01-01

Fires in croplands, plantations, and rangelands contribute significantly to fire emissions in the United States, yet are often overshadowed by wildland fires in efforts to develop inventories or estimate responses to climate change. Here we quantified decadal trends, interannual variability, and seasonality of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) observations of active fires (thermal anomalies) as a function of management type in the contiguous U.S. during 2001–2010. We used the Monitoring Trends in Burn Severity database to identify active fires within the perimeter of large wildland fires and land cover maps to identify active fires in croplands. A third class of fires defined as prescribed/other included all residual satellite active fire detections. Large wildland fires were the most variable of all three fire types and had no significant annual trend in the contiguous U.S. during 2001–2010. Active fires in croplands, in contrast, increased at a rate of 3.4% per year. Cropland and prescribed/other fire types combined were responsible for 77% of the total active fire detections within the U.S and were most abundant in the south and southeast. In the west, cropland active fires decreased at a rate of 5.9% per year, likely in response to intensive air quality policies. Potential evaporation was a dominant regulator of the interannual variability of large wildland fires, but had a weaker influence on the other two fire types. Our analysis suggests it may be possible to modify landscape fire emissions within the U.S. by influencing the way fires are used in managed ecosystems. Key Points Wildland, cropland, and prescribed fires had different trends and patterns Sensitivity to climate varied with fire type Intensity of air quality regulation influenced cropland burning trends PMID:26213662

Management and climate contributions to satellite-derived active fire trends in the contiguous United States.

PubMed

Lin, Hsiao-Wen; McCarty, Jessica L; Wang, Dongdong; Rogers, Brendan M; Morton, Douglas C; Collatz, G James; Jin, Yufang; Randerson, James T

2014-04-01

Fires in croplands, plantations, and rangelands contribute significantly to fire emissions in the United States, yet are often overshadowed by wildland fires in efforts to develop inventories or estimate responses to climate change. Here we quantified decadal trends, interannual variability, and seasonality of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) observations of active fires (thermal anomalies) as a function of management type in the contiguous U.S. during 2001-2010. We used the Monitoring Trends in Burn Severity database to identify active fires within the perimeter of large wildland fires and land cover maps to identify active fires in croplands. A third class of fires defined as prescribed/other included all residual satellite active fire detections. Large wildland fires were the most variable of all three fire types and had no significant annual trend in the contiguous U.S. during 2001-2010. Active fires in croplands, in contrast, increased at a rate of 3.4% per year. Cropland and prescribed/other fire types combined were responsible for 77% of the total active fire detections within the U.S and were most abundant in the south and southeast. In the west, cropland active fires decreased at a rate of 5.9% per year, likely in response to intensive air quality policies. Potential evaporation was a dominant regulator of the interannual variability of large wildland fires, but had a weaker influence on the other two fire types. Our analysis suggests it may be possible to modify landscape fire emissions within the U.S. by influencing the way fires are used in managed ecosystems. Wildland, cropland, and prescribed fires had different trends and patternsSensitivity to climate varied with fire typeIntensity of air quality regulation influenced cropland burning trends.

Comparison of fire scars, fire atlases, and satellite data in the northwestern United States

Treesearch

Lauren B. Shapiro-Miller; Emily K. Heyerdahl; Penelope Morgan

2007-01-01

We evaluated agreement in the location and occurrence of 20th century fires recorded in digital fire atlases with those inferred from fire scars that we collected systematically at one site in Idaho and from existing fire-scar reconstructions at four sites in Washington. Fire perimeters were similar for two of three 20th century fires in Idaho (1924 and 1986). Overall...

Climate drives inter-annual variability in probability of high severity fire occurrence in the western United States

NASA Astrophysics Data System (ADS)

Keyser, Alisa; Westerling, Anthony LeRoy

2017-05-01

A long history of fire suppression in the western United States has significantly changed forest structure and ecological function, leading to increasingly uncharacteristic fires in terms of size and severity. Prior analyses of fire severity in California forests showed that time since last fire and fire weather conditions predicted fire severity very well, while a larger regional analysis showed that topography and climate were important predictors of high severity fire. There has not yet been a large-scale study that incorporates topography, vegetation and fire-year climate to determine regional scale high severity fire occurrence. We developed models to predict the probability of high severity fire occurrence for the western US. We predict high severity fire occurrence with some accuracy, and identify the relative importance of predictor classes in determining the probability of high severity fire. The inclusion of both vegetation and fire-year climate predictors was critical for model skill in identifying fires with high fractional fire severity. The inclusion of fire-year climate variables allows this model to forecast inter-annual variability in areas at future risk of high severity fire, beyond what slower-changing fuel conditions alone can accomplish. This allows for more targeted land management, including resource allocation for fuels reduction treatments to decrease the risk of high severity fire.

Evaluating Fire Risk in the Northeastern United States in the Past, Present, and Future

NASA Astrophysics Data System (ADS)

Miller, D.; Bradley, R. S.

2017-12-01

One poorly understood consequence of climate change is its effects on extreme events such as wildfires. Robust associations between wildfire frequency and climatic variability have been shown to exist, indicating that future climate change may continue to have a significant effect on wildfire activity. The Northeastern United States (NEUS) has seen some of the most infamous and largest historic fires in North America, such as the Miramichi Fire of 1825 and the fires of 1947. Although return intervals for large fires in the NEUS are long (hundreds of years), wildfires have played a critical role in ecosystem development and forest structure in the region. Understanding and predicting fire occurrence and vulnerability in the NEUS, especially in a changing climate, is economically and culturally important yet remains difficult due to human impacts (i.e. fire suppression activities and human disturbance). Thus, an alternative method for investigating fire risk in the NEUS is needed. Here, we present a compilation of meteorological data collected from Automated Surface Observing Systems (ASOS) from the NEUS throughout the 20th century through present day. We use these data to compute fifteen common "fire danger indices" employed in the USA and Canada to investigate changes in the region's fire risk over time, as well as the skill of each of these indices at predicting wildfire activity relative to the historical record of fires in the NEUS. We use dynamically-downscaled regional climate model output for the 21st century to project future wildfire activity based on the fire danger indices capable of capturing historical fire activity in the NEUS. These projections will aid in predicting how fire risk in the NEUS will evolve with anticipated climate change.

Single motor unit firing rate after stroke is higher on the less-affected side during stable low-level voluntary contractions

PubMed Central

McNulty, Penelope A.; Lin, Gaven; Doust, Catherine G.

2014-01-01

Muscle weakness is the most common outcome after stroke and a leading cause of adult-acquired motor disability. Single motor unit properties provide insight into the mechanisms of post-stroke motor impairment. Motor units on the more-affected side are reported to have lower peak firing rates, reduced discharge variability and a more compressed dynamic range than healthy subjects. The activity of 169 motor units was discriminated from surface electromyography in 28 stroke patients during sustained voluntary contractions 10% of maximal and compared to 110 units recorded in 16 healthy subjects. Motor units were recorded in three series: ankle dorsiflexion, wrist flexion and elbow flexion. Mean firing rates after stroke were significantly lower on the more-affected than the less-affected side (p < 0.001) with no differences between dominant and non-dominant sides for healthy subjects. When data were combined, firing rates on the less-affected side were significantly higher than those either on the more-affected side or healthy subjects (p < 0.001). Motor unit mean firing rate was higher in the upper-limb than the lower-limb (p < 0.05). The coefficient of variation of motor unit discharge rate was lower for motor units after stroke compared to controls for wrist flexion (p < 0.05) but not ankle dorsiflexion. However the dynamic range of motor units was compressed only for motor units on the more-affected side during wrist flexion. Our results show that the pathological change in motor unit firing rate occurs on the less-affected side after stroke and not the more-affected side as previously reported, and suggest that motor unit behavior recorded in a single muscle after stroke cannot be generalized to muscles acting on other joints even within the same limb. These data emphasize that the less-affected side does not provide a valid control for physiological studies on the more-affected side after stroke and that both sides should be compared to data from age- and sex

Climatic and Landscape Influences on Fire Regimes from 1984 to 2010 in the Western United States

PubMed Central

Liu, Zhihua; Wimberly, Michael C.

2015-01-01

An improved understanding of the relative influences of climatic and landscape controls on multiple fire regime components is needed to enhance our understanding of modern fire regimes and how they will respond to future environmental change. To address this need, we analyzed the spatio-temporal patterns of fire occurrence, size, and severity of large fires (> 405 ha) in the western United States from 1984–2010. We assessed the associations of these fire regime components with environmental variables, including short-term climate anomalies, vegetation type, topography, and human influences, using boosted regression tree analysis. Results showed that large fire occurrence, size, and severity each exhibited distinctive spatial and spatio-temporal patterns, which were controlled by different sets of climate and landscape factors. Antecedent climate anomalies had the strongest influences on fire occurrence, resulting in the highest spatial synchrony. In contrast, climatic variability had weaker influences on fire size and severity and vegetation types were the most important environmental determinants of these fire regime components. Topography had moderately strong effects on both fire occurrence and severity, and human influence variables were most strongly associated with fire size. These results suggest a potential for the emergence of novel fire regimes due to the responses of fire regime components to multiple drivers at different spatial and temporal scales. Next-generation approaches for projecting future fire regimes should incorporate indirect climate effects on vegetation type changes as well as other landscape effects on multiple components of fire regimes. PMID:26465959

Unit 5, STA. 50+00+RB, retaining wall at Orner Building & ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 5, STA. 50+00+RB, retaining wall at Orner Building & First U.M. Church Rectory-detail - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

DEMONSTRATION OF NATURAL GAS REBURN FOR NOX EMISSIONS REDUCTION AT OHIO EDISON COMPANY'S CYCLONE-FIRED NILES PLANT UNIT NO. 1

EPA Science Inventory

The report describes a demonstration of reburning on a cyclone-fired boiler. The project included a review of reburn technology, aerodynamic flow model testing, long-term load dispatch testing, and boiler tube wall thickness monitoring. The report also contains a description of O...

Evacuation Preparedness in the Event of Fire in Intensive Care Units in Sweden: More is Needed.

PubMed

Löfqvist, Erika; Oskarsson, Åsa; Brändström, Helge; Vuorio, Alpo; Haney, Michael

2017-06-01

Introduction Hospitals, including intensive care units (ICUs), can be subject to threat from fire and require urgent evacuation. Hypothesis The hypothesis was that the current preparedness for ICU evacuation for fire in the national public hospital system in a wealthy country was very good, using Sweden as model. An already validated questionnaire for this purpose was adapted to national/local circumstances and translated into Swedish. It aimed to elicit information concerning fire response planning, personnel education, training, and exercises. Questionnaire results (yes/no answers) were collected and answers collated to assess grouped responses. Frequencies of responses were determined. While a written hospital plan for fire response and evacuation was noted by all responders, personnel familiarity with the plan was less frequent. Deficiencies were reported concerning all categories: lack of written fire response plan for ICU, lack of personnel education in this, and lack of practical exercises to practice urgent evacuation in the event of fire. These findings were interpreted as an indication of risk for worse consequences for patients in the event of fire and ICU evacuation among the hospitals in the country that was assessed, despite clear regulations and requirements for these. The exact reasons for this lack of compliance with existing laws was not clear, though there are many possible explanations. To remedy this, more attention is needed concerning recognizing risk related to lack of preparedness. Where there exists a goal of high-quality work in the ICU, this should include general leadership and medical staff preparedness in the event of urgent ICU evacuation. Löfqvist E , Oskarsson A , Brändström H , Vuorio A , Haney M . Evacuation preparedness in the event of fire in intensive care units in Sweden: more is needed. Prehosp Disaster Med. 2017;32(3):317-320.

Unit 4, STA. 59+00+ lb, sideslope with masonry walls (without ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 4, STA. 59+00+ lb, sideslope with masonry walls (without parapets), Cambria Iron Company National Historic Landmark-Context - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

Contractile function and motor unit firing rates of the human hamstrings.

PubMed

Kirk, Eric A; Rice, Charles L

2017-01-01

Neuromuscular properties of the lower limb in health, aging, and disease are well described for major lower limb muscles comprising the quadriceps, triceps surae, and dorsiflexors, with the notable exception of the posterior thigh (hamstrings). The purpose of this study was to further characterize major muscles of the lower limb by comprehensively exploring contractile properties in relation to spinal motor neuron output expressed as motor unit firing rates (MUFRs) in the hamstrings of 11 (26.5 ± 3.8) young men. Maximal isometric voluntary contraction (MVC), voluntary activation, stimulated contractile properties including a force-frequency relationship, and MUFRs from submaximal to maximal voluntary contractile intensities were assessed in the hamstrings. Strength and MUFRs were assessed at two presumably different muscle lengths by varying the knee joint angles (90° and 160°). Knee flexion MVCs were 60-70% greater in the extended position (160°). The frequency required to elicit 50% of maximum tetanic torque was 16-17 Hz. Mean MUFRs at 25-50% MVC were 9-31% less in the biceps femoris compared with the semimembranosus-semitendinosus group. Knee joint angle (muscle length) influenced MUFRs such that mean MUFRs were greater in the shortened (90°) position at 50% and 100% MVC. Compared with previous reports, mean maximal MUFRs in the hamstrings are greater than those in the quadriceps and triceps surae and somewhat less than those in the tibialis anterior. Mean maximal MUFRs in the hamstrings are influenced by changes in knee joint angle, with lower firing rates in the biceps femoris compared with the semimembranosus-semitendinosus muscle group. We studied motor unit firing rates (MUFRs) at various voluntary contraction intensities in the hamstrings, one of the only major lower limb muscles to have MUFRs affected by muscle length changes. Within the hamstrings muscle-specific differences have greater impact on MUFRs than length changes, with the biceps femoris

Characterization of potential fire regimes: applying landscape ecology to fire management in Mexico

NASA Astrophysics Data System (ADS)

Jardel, E.; Alvarado, E.; Perez-Salicrup, D.; Morfín-Rios, J.

2013-05-01

Knowledge and understanding of fire regimes is fundamental to design sound fire management practices. The high ecosystem diversity of Mexico offers a great challenge to characterize the fire regime variation at the landscape level. A conceptual model was developed considering the main factors controlling fire regimes: climate and vegetation cover. We classified landscape units combining bioclimatic zones from the Holdridge life-zone system and actual vegetation cover. Since bioclimatic conditions control primary productivity and biomass accumulation (potential fuel), each landscape unit was considered as a fuel bed with a particular fire intensity and behavior potential. Climate is also a determinant factor of post-fire recovery rates of fuel beds, and climate seasonality (length of the dry and wet seasons) influences fire probability (available fuel and ignition efficiency). These two factors influence potential fire frequency. Potential fire severity can be inferred from fire frequency, fire intensity and behavior, and vegetation composition and structure. Based in the conceptual model, an exhaustive literature review and expert opinion, we developed rules to assign a potential fire regime (PFR) defined by frequency, intensity and severity (i.e. fire regime) to each bioclimatic-vegetation landscape unit. Three groups and eight types of potential fire regimes were identified. In Group A are fire-prone ecosystems with frequent low severity surface fires in grasslands (PFR type I) or forests with long dry season (II) and infrequent high-severity fires in chaparral (III), wet temperate forests (IV, fire restricted by humidity), and dry temperate forests (V, fire restricted by fuel recovery rate). Group B includes fire-reluctant ecosystems with very infrequent or occasional mixed severity surface fires limited by moisture in tropical rain forests (VI) or fuel availability in seasonally dry tropical forests (VII). Group C and PFR VIII include fire-free environments

Prevalence and correlates of fire-setting in the United States: results from the National Epidemiological Survey on Alcohol and Related Conditions.

PubMed

Vaughn, Michael G; Fu, Qiang; Delisi, Matt; Wright, John Paul; Beaver, Kevin M; Perron, Brian E; Howard, Matthew O

2010-01-01

Fire-setting is a serious and costly form of antisocial behavior. Our objective in this study was to examine the prevalence and correlates of intentional fire-setting behavior in the United States. Data were derived from a nationally representative sample of US residents 18 years and older. Structured psychiatric interviews (N = 43,093) were completed by trained lay interviewers between 2001 and 2002. Fire-setting as well as mood, anxiety, substance use, and personality disorders of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition were assessed with the Alcohol Use Disorder and Associated Disabilities Interview Schedule (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) version. The prevalence of lifetime fire-setting in the US population was 1.0%. Respondents who were men, white, 18 to 35 years old, born in the United States, and living in the western region of the United States had significantly higher rates of fire-setting than their counterparts. Fire-setting was significantly associated with a wide range of antisocial behaviors. Multivariate logistic regression analyses identified strong associations between lifetime alcohol and marijuana use disorders, conduct disorder, antisocial and obsessive-compulsive personality disorders, and family history of antisocial behavior. Intentional illicit fire-setting behavior is associated with a broad array of antisocial behaviors and psychiatric comorbidities. Given the substantial personal and social costs related to arson, prevention and treatment interventions targeting fire-setters potentially could save lives and property. 2010 Elsevier Inc. All rights reserved.

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire-extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire-extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

46 CFR 107.235 - Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Servicing of hand portable fire extinguishers, semi-portable fire extinguishers and fixed fire extinguishing systems. 107.235 Section 107.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND...

Aerosols from fires: an examination of the effects on ozone photochemistry in the Western United States.

PubMed

Jiang, Xiaoyan; Wiedinmyer, Christine; Carlton, Annmarie G

2012-11-06

This study presents a first attempt to investigate the roles of fire aerosols in ozone (O(3)) photochemistry using an online coupled meteorology-chemistry model, the Weather Research and Foresting model with Chemistry (WRF-Chem). Four 1-month WRF-Chem simulations for August 2007, with and without fire emissions, were carried out to assess the sensitivity of O(3) predictions to the emissions and subsequent radiative feedbacks associated with large-scale fires in the Western United States (U.S.). Results show that decreases in planetary boundary layer height (PBLH) resulting from the radiative effects of fire aerosols and increases in emissions of nitrogen oxides (NO(x)) and volatile organic compounds (VOCs) from the fires tend to increase modeled O(3) concentrations near the source. Reductions in downward shortwave radiation reaching the surface and surface temperature due to fire aerosols cause decreases in biogenic isoprene emissions and J(NO(2)) photolysis rates, resulting in reductions in O(3) concentrations by as much as 15%. Thus, the results presented in this study imply that considering the radiative effects of fire aerosols may reduce O(3) overestimation by traditional photochemical models that do not consider fire-induced changes in meteorology; implementation of coupled meteorology-chemistry models are required to simulate the atmospheric chemistry impacted by large-scale fires.

The Effects of Exercise on the Firing Patterns of Single Motor Units.

ERIC Educational Resources Information Center

Cracraft, Joe D.

In this study, the training effects of static and dynamic exercise programs on the firing patterns of 450 single motor units (SMU) in the human tibialis anterior muscle were investigated. In a six week program, the static group (N=5) participated in daily high intensity, short duration, isometric exercises while the dynamic group (N=5)…

Fire Ant Bites

MedlinePlus

... Favorite Name: Category: Share: Yes No, Keep Private Fire Ant Bites Share | Fire ants are aggressive, venomous insects that have pinching ... across the United States, even into Puerto Rico. Fire ant stings usually occur on the feet or ...

Fire in the OR--developing a fire safety plan.

PubMed

McCarthy, Patricia M; Gaucher, Kenneth A

2004-03-01

Approximately 100 operating room fire occur each year in the United States. Although rare, fire in a perioperative setting can be disastrous for both patients and staff members. It is crucial that all perioperative departments have a well thought out and previously rehearsed fire plan in place. Multidisciplinary planning and implementation of regularly scheduled and scripted fire drills are essential to prevent adverse outcomes. Fire drills ensure that all staff members are familiar with the use and location of fire pull stations, fire extinguishers, and fire blankets. Fire drills also prepare staff members to evacuate the OR area if necessary. This article provides the information and framework necessary to develop and implement comprehensive OR fire safety plans that could make the difference between life and death in a fire emergency.

"Fire Moss" Cover and Function in Severely Burned Forests of the Western United States

NASA Astrophysics Data System (ADS)

Grover, H.; Doherty, K.; Sieg, C.; Robichaud, P. R.; Fulé, P. Z.; Bowker, M.

2017-12-01

With wildfires increasing in severity and extent throughout the Western United States, land managers need new tools to stabilize recently burned ecosystems. "Fire moss" consists of three species, Ceratodon purpureus, Funaria hygrometrica, and Bryum argentum. These mosses colonize burned landscapes quickly, aggregate soils, have extremely high water holding capacity, and can be grown rapidly ex-situ. In this talk, I will focus on our efforts to understand how Fire Moss naturally interacts with severely burned landscapes. We examined 14 fires in Arizona, New Mexico, Washington, and Idaho selecting a range of times since fire, and stratified plots within each wildfire by winter insolation and elevation. At 75+ plots we measured understory plant cover, ground cover, Fire Moss cover, and Fire Moss reproductive effort. On plots in the Southwest, we measured a suite of soil characteristics on moss covered and adjacent bare soil including aggregate stability, shear strength, compressional strength, and infiltration rates. Moss cover ranged from 0-75% with a mean of 16% across all plots and was inversely related to insolation (R2 = .32, p = <.01), directly related to elevation (R2 = .13, p = .02), and not related to slope (R2 = .02, p =.41). Moss covered areas had twice as much shear strength and compressional strength, and three times higher aggregate stability and infiltration rates as adjacent bare ground. These results will allow us to model locations where Fire Moss will naturally increase postfire hillslope soil stability, locations for targeting moss restoration efforts, and suggest that Fire Moss could be a valuable tool to mitigate post wildfire erosion.

Human presence diminishes the importance of climate in driving fire activity across the United States

USGS Publications Warehouse

Syphard, Alexandra D.; Keeley, Jon E.; Pfaff, Anne Hopkins; Ferschweiler, Ken

2017-01-01

Growing human and ecological costs due to increasing wildfire are an urgent concern in policy and management, particularly given projections of worsening fire conditions under climate change. Thus, understanding the relationship between climatic variation and fire activity is a critically important scientific question. Different factors limit fire behavior in different places and times, but most fire-climate analyses are conducted across broad spatial extents that mask geographical variation. This could result in overly broad or inappropriate management and policy decisions that neglect to account for regionally specific or other important factors driving fire activity. We developed statistical models relating seasonal temperature and precipitation variables to historical annual fire activity for 37 different regions across the continental United States and asked whether and how fire-climate relationships vary geographically, and why climate is more important in some regions than in others. Climatic variation played a significant role in explaining annual fire activity in some regions, but the relative importance of seasonal temperature or precipitation, in addition to the overall importance of climate, varied substantially depending on geographical context. Human presence was the primary reason that climate explained less fire activity in some regions than in others. That is, where human presence was more prominent, climate was less important. This means that humans may not only influence fire regimes but their presence can actually override, or swamp out, the effect of climate. Thus, geographical context as well as human influence should be considered alongside climate in national wildfire policy and management.

Statistically rigorous calculations do not support common input and long-term synchronization of motor-unit firings

PubMed Central

Kline, Joshua C.

2014-01-01

Over the past four decades, various methods have been implemented to measure synchronization of motor-unit firings. In this work, we provide evidence that prior reports of the existence of universal common inputs to all motoneurons and the presence of long-term synchronization are misleading, because they did not use sufficiently rigorous statistical tests to detect synchronization. We developed a statistically based method (SigMax) for computing synchronization and tested it with data from 17,736 motor-unit pairs containing 1,035,225 firing instances from the first dorsal interosseous and vastus lateralis muscles—a data set one order of magnitude greater than that reported in previous studies. Only firing data, obtained from surface electromyographic signal decomposition with >95% accuracy, were used in the study. The data were not subjectively selected in any manner. Because of the size of our data set and the statistical rigor inherent to SigMax, we have confidence that the synchronization values that we calculated provide an improved estimate of physiologically driven synchronization. Compared with three other commonly used techniques, ours revealed three types of discrepancies that result from failing to use sufficient statistical tests necessary to detect synchronization. 1) On average, the z-score method falsely detected synchronization at 16 separate latencies in each motor-unit pair. 2) The cumulative sum method missed one out of every four synchronization identifications found by SigMax. 3) The common input assumption method identified synchronization from 100% of motor-unit pairs studied. SigMax revealed that only 50% of motor-unit pairs actually manifested synchronization. PMID:25210152

Particulate matter and black carbon optical properties and emission factors from prescribed fires in the southeastern United States

EPA Pesticide Factsheets

This dataset provides all data used to generate the figures and tables in the article entitled Particulate matter and black carbon optical properties and emission factors from prescribed fires in the southeastern United States published in the Journal of Geophysical Research: AtmospheresThis dataset is associated with the following publication:Holder , A., G. Hagler , J. Aurell, M. Hays , and B. Gullett. Particulate matter and black carbon optical properties and emission factors from prescribed fires in the southeastern United States. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES. American Geophysical Union, Washington, DC, USA, 121(7): 3465-3483, (2016).

Using GRACE-Derived Water and Moisture Products as a Predictive Tool for Fire Response in the Contiguous United States

NASA Astrophysics Data System (ADS)

Rousseau, N. J.; Jensen, D.; Zajic, B.; Rodell, M.; Reager, J. T., II

2015-12-01

Understanding the relationship between wildfire activity and soil moisture in the United States has been difficult to assess, with limited ability to determine areas that are at high risk. This limitation is largely due to complex environmental factors at play, especially as they relate to alternating periods of wet and dry conditions, and the lack of remotely-sensed products. Recent drought conditions and accompanying low Fuel Moisture Content (FMC) have led to disastrous wildfire outbreaks causing economic loss, property damage, and environmental degradation. Thus, developing a programmed toolset to assess the relationship between soil moisture, which contributes greatly to FMC and fire severity, can establish the framework for determining overall wildfire risk. To properly evaluate these parameters, we used data assimilated from the Gravity Recovery and Climate Experiment (GRACE) and data from the Fire Program Analysis fire-occurrence database (FPA FOD) to determine the extent soil moisture affects fire activity. Through these datasets, we produced correlation and regression maps at a coarse resolution of 0.25 degrees for the contiguous United States. These fire-risk products and toolsets proved the viability of this methodology, allowing for the future incorporation of more GRACE-derived water parameters, MODIS vegetation indices, and other environmental datasets to refine the model for fire risk. Additionally, they will allow assessment to national-scale early fire management and provide responders with a predictive tool to better employ early decision-support to areas of high risk during regions' respective fire season(s).

Fire development and wall endurance in sandwich and wood-frame structures

Treesearch

Carlton A. Holmes; Herbert W. Eickner; John J. Brenden; Curtis C. Peters; Robert H. White

1980-01-01

Large-scale fire tests were conducted on seven 16- by 24-foot structures. Four of these structures were of sandwich construction with cores of plastic or paper honeycomb and three were of wood-frame construction. The wasss were loaded to a computer design loading, and the fire endurance determined under a fire exposure from a typical building contents loading of 4-1/2...

Contractile function and motor unit firing rates of the human hamstrings

PubMed Central

Kirk, Eric A.

2016-01-01

Neuromuscular properties of the lower limb in health, aging, and disease are well described for major lower limb muscles comprising the quadriceps, triceps surae, and dorsiflexors, with the notable exception of the posterior thigh (hamstrings). The purpose of this study was to further characterize major muscles of the lower limb by comprehensively exploring contractile properties in relation to spinal motor neuron output expressed as motor unit firing rates (MUFRs) in the hamstrings of 11 (26.5 ± 3.8) young men. Maximal isometric voluntary contraction (MVC), voluntary activation, stimulated contractile properties including a force-frequency relationship, and MUFRs from submaximal to maximal voluntary contractile intensities were assessed in the hamstrings. Strength and MUFRs were assessed at two presumably different muscle lengths by varying the knee joint angles (90° and 160°). Knee flexion MVCs were 60–70% greater in the extended position (160°). The frequency required to elicit 50% of maximum tetanic torque was 16–17 Hz. Mean MUFRs at 25–50% MVC were 9–31% less in the biceps femoris compared with the semimembranosus-semitendinosus group. Knee joint angle (muscle length) influenced MUFRs such that mean MUFRs were greater in the shortened (90°) position at 50% and 100% MVC. Compared with previous reports, mean maximal MUFRs in the hamstrings are greater than those in the quadriceps and triceps surae and somewhat less than those in the tibialis anterior. Mean maximal MUFRs in the hamstrings are influenced by changes in knee joint angle, with lower firing rates in the biceps femoris compared with the semimembranosus-semitendinosus muscle group. NEW & NOTEWORTHY We studied motor unit firing rates (MUFRs) at various voluntary contraction intensities in the hamstrings, one of the only major lower limb muscles to have MUFRs affected by muscle length changes. Within the hamstrings muscle-specific differences have greater impact on MUFRs than length changes

The development of landscape-scale ecological units and their application to the greater Huachuca Mountains fire planning process

Treesearch

Larry E. Laing; David Gori; James T. Jones

2005-01-01

The multi-partner Greater Huachuca Mountains fire planning effort involves over 500,000 acres of public and private lands. This large area supports distinct landscapes that have evolved with fire. Utilizing GIS as a tool, the United States Forest Service (USFS), General Ecosystem Survey (GES), and Natural Resources Conservation Service (NRCS) State Soil Geographic...

Fire Ant Decapitating Fly Cooperative Release Programs (1994–2008): Two Pseudacteon Species, P. tricuspis and P. curvatus, Rapidly Expand Across Imported Fire Ant Populations in the Southeastern United States

PubMed Central

Callcott, Anne-Marie A.; Porter, Sanford D.; Weeks, Ronald D.; “Fudd” Graham, L. C.; Johnson, Seth J.; Gilbert, Lawrence E.

2011-01-01

Natural enemies of the imported fire ants, Solenopsis invicta Buren S. richteri Forel (Hymenoptera: Formicidae), and their hybrid, include a suite of more than 20 fire ant decapitating phorid flies from South America in the genus Pseudacteon. Over the past 12 years, many researchers and associates have cooperated in introducing several species as classical or self-sustaining biological control agents in the United States. As a result, two species of flies, Pseudacteon tricuspis Borgmeier and P. curvatus Borgmeier (Diptera: Phoridae), are well established across large areas of the southeastern United States. Whereas many researchers have published local and state information about the establishment and spread of these flies, here distribution data from both published and unpublished sources has been compiled for the entire United States with the goal of presenting confirmed and probable distributions as of the fall of 2008. Documented rates of expansion were also used to predict the distribution of these flies three years later in the fall of 2011. In the fall of 2008, eleven years after the first successful release, we estimate that P. tricuspis covered about 50% of the fire ant quarantined area and that it will occur in almost 65% of the quarantine area by 2011. Complete coverage of the fire ant quarantined area will be delayed or limited by this species' slow rate of spread and frequent failure to establish in more northerly portions of the fire ant range and also, perhaps, by its preference for red imported fire ants (S. invicta). Eight years after the first successful release of P. curvatus, two biotypes of this species (one biotype occurring predominantly in the black and hybrid imported fire ants and the other occurring in red imported fire ants) covered almost 60% of the fire ant quarantined area. We estimate these two biotypes will cover almost 90% of the quarantine area by 2011 and 100% by 2012 or 2013. Strategic selection of several distributional gaps

Unit 4, STA. 59+00+lb sideslope with masonry walls (withouth parapets), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 4, STA. 59+00+lb sideslope with masonry walls (withouth parapets), Cambria Iron Company National Historic Landmark-detail - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

Unit 4, STA. 31+00+lb, sideslope with concrete walls (without parapets), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 4, STA. 31+00+lb, sideslope with concrete walls (without parapets), Cambria Iron Company National Historic Landmark-Context - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

Prescribed fire as a means of reducing forest carbon emissions in the western United States.

PubMed

Wiedinmyer, Christine; Hurteau, Matthew D

2010-03-15

Carbon sequestration by forested ecosystems offers a potential climate change mitigation benefit. However, wildfire has the potential to reverse this benefit In the western United States, climate change and land management practices have led to increases in wildfire intensity and size. One potential means of reducing carbon emissions from wildfire is the use of prescribed burning,which consumes less biomass and therefore releases less carbon to the atmosphere. This study uses a regional fire emissions model to estimate the potential reduction in fire emissions when prescribed burning is applied in dry, temperate forested systems of the western U.S. Daily carbon dioxide (CO(2)) fire emissions for 2001-2008 were calculated for the western U.S. for two cases: a default wildfire case and one in which prescribed burning was applied. Wide-scale prescribed fire application can reduce CO(2) fire emissions for the western U.S. by 18-25%1 in the western U.S., and by as much as 60% in specific forest systems. Although this work does not address important considerations such as the feasibility of implementing wide-scale prescribed fire management or the cumulative emissions from repeated prescribed burning, it does provide constraints on potential carbon emission reductions when prescribed burning is used.

Development of prescribed fire as a silvicultural tool for the upland oak forests of the eastern United States

Treesearch

Patrick H. Brose

2014-01-01

In the past 40 years, the perception of periodic fire in upland oak (Quercus spp.) forests in the eastern United States has changed dramatically. Once thought of as a wholly destructive force, periodic fire is now considered an important disturbance whose absence is a major contributing factor to oak regeneration problems. This change in attitude and...

Statistically rigorous calculations do not support common input and long-term synchronization of motor-unit firings.

PubMed

De Luca, Carlo J; Kline, Joshua C

2014-12-01

Over the past four decades, various methods have been implemented to measure synchronization of motor-unit firings. In this work, we provide evidence that prior reports of the existence of universal common inputs to all motoneurons and the presence of long-term synchronization are misleading, because they did not use sufficiently rigorous statistical tests to detect synchronization. We developed a statistically based method (SigMax) for computing synchronization and tested it with data from 17,736 motor-unit pairs containing 1,035,225 firing instances from the first dorsal interosseous and vastus lateralis muscles--a data set one order of magnitude greater than that reported in previous studies. Only firing data, obtained from surface electromyographic signal decomposition with >95% accuracy, were used in the study. The data were not subjectively selected in any manner. Because of the size of our data set and the statistical rigor inherent to SigMax, we have confidence that the synchronization values that we calculated provide an improved estimate of physiologically driven synchronization. Compared with three other commonly used techniques, ours revealed three types of discrepancies that result from failing to use sufficient statistical tests necessary to detect synchronization. 1) On average, the z-score method falsely detected synchronization at 16 separate latencies in each motor-unit pair. 2) The cumulative sum method missed one out of every four synchronization identifications found by SigMax. 3) The common input assumption method identified synchronization from 100% of motor-unit pairs studied. SigMax revealed that only 50% of motor-unit pairs actually manifested synchronization. Copyright © 2014 the American Physiological Society.

Studying interregional wildland fire engine assignments for large fire suppression

Treesearch

Erin J. Belval; Yu Wei; David E. Calkin; Crystal S. Stonesifer; Matthew P. Thompson; John R. Tipton

2017-01-01

One crucial component of large fire response in the United States (US) is the sharing of wildland firefighting resources between regions: resources from regions experiencing low fire activity supplement resources in regions experiencing high fire activity. An important step towards improving the efficiency of resource sharing and related policies is to develop a better...

Fire investigation

NASA Astrophysics Data System (ADS)

Gomberg, A.

There was considerable progress made on several fronts of fire investigation in the United States in recent years. Progress was made in increasing the quantity of fire investigation and reporting, through efforts to develop the National Fire Incident Reporting System. Improving overall quality of fire investigation is the objective of efforts such as the Fire Investigation Handbook, which was developed and published by the National Bureau of Standards, and the upgrading and expanding of the ""dictionary'' of fire investigation and reporting, the NFPA 901, Uniform Coding for Fire Protection, system. The science of fire investigation as furthered also by new approaches to post fire interviews being developed at the University of Washington, and by in-depth research into factors involved in several large loss fires, including the MGM Grand Hotel in Las Vegas. Finally, the use of special study fire investigations - in-depth investigations concentrating on specific fire problems - is producing new glimpses into the nature of the national fire problem. A brief description of the status of efforts in each of these areas is discussed.

46 CFR 108.401 - Fire main system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Fire main system. 108.401 Section 108.401 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.401 Fire main system. Each unit must have a fire main system. ...

46 CFR 108.401 - Fire main system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire main system. 108.401 Section 108.401 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.401 Fire main system. Each unit must have a fire main system. ...

46 CFR 108.401 - Fire main system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Fire main system. 108.401 Section 108.401 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.401 Fire main system. Each unit must have a fire main system. ...

46 CFR 108.401 - Fire main system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Fire main system. 108.401 Section 108.401 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.401 Fire main system. Each unit must have a fire main system. ...

46 CFR 108.401 - Fire main system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fire main system. 108.401 Section 108.401 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.401 Fire main system. Each unit must have a fire main system. ...

Post-fire regeneration across a fire severity gradient in the southern Cascades

Treesearch

Justin Crotteau; Morgan Varner; Martin Ritchie

2012-01-01

Large scale, high-severity fires are increasing in the western United States. Despite this trend, there have been few studies investigating post-fire tree regeneration. We established a study in the footprint of the 2000 Storrie Fire, a 23,000 ha wildfire that occurred in northern California, USA. We used a stratified sampling design to quantify post-fire vegetation...

Fire weather technology for fire agrometeorology operations

Treesearch

Francis Fujioka

2008-01-01

Even as the magnitude of wildfire problems increases globally, United Nations agencies are acting to mitigate the risk of wildfire disasters to members. Fire management organizations worldwide may vary considerably in operational scope, depending on the number and type of resources an organization manages. In any case, good fire weather information is vital. This paper...

Full-scale flammability test data for validation of aircraft fire mathematical models

NASA Technical Reports Server (NTRS)

Kuminecz, J. F.; Bricker, R. W.

1982-01-01

Twenty-five large scale aircraft flammability tests were conducted in a Boeing 737 fuselage at the NASA Johnson Space Center (JSC). The objective of this test program was to provide a data base on the propagation of large scale aircraft fires to support the validation of aircraft fire mathematical models. Variables in the test program included cabin volume, amount of fuel, fuel pan area, fire location, airflow rate, and cabin materials. A number of tests were conducted with jet A-1 fuel only, while others were conducted with various Boeing 747 type cabin materials. These included urethane foam seats, passenger service units, stowage bins, and wall and ceiling panels. Two tests were also included using special urethane foam and polyimide foam seats. Tests were conducted with each cabin material individually, with various combinations of these materials, and finally, with all materials in the cabin. The data include information obtained from approximately 160 locations inside the fuselage.

Development of a fire weather index using meteorological observations within the Northeast United States

Treesearch

Michael J. Erickson; Joseph J. Charney; Brian A. Colle

2016-01-01

A fire weather index (FWI) is developed using wildfire occurrence data and Automated Surface Observing System weather observations within a subregion of the northeastern United States (NEUS) from 1999 to 2008. Average values of several meteorological variables, including near-surface temperature, relative humidity, dewpoint, wind speed, and cumulative daily...

Teaching About Fire Safety.

ERIC Educational Resources Information Center

Brady, Holly; Arnold, Anne Jurmu

1982-01-01

This unit on fire safety teaches students how to act in or during a fire and presents fire prevention measures that students can implement at home. Two reproducible masters concerning fire safety and prevention are presented along with class activities, student reading resources, and organizations and companies that offer classroom materials about…

How to generate and interpret fire characteristics charts for surface and crown fire behavior

Treesearch

Patricia L. Andrews; Faith Ann Heinsch; Luke Schelvan

2011-01-01

A fire characteristics chart is a graph that presents primary related fire behavior characteristics-rate of spread, flame length, fireline intensity, and heat per unit area. It helps communicate and interpret modeled or observed fire behavior. The Fire Characteristics Chart computer program plots either observed fire behavior or values that have been calculated by...

Passive fire protection in high density village (case study, Bustaman Semarang)

NASA Astrophysics Data System (ADS)

Sukawi, Sukawi; Wahyu Firmandhani, Satriya; Hardiman, Gagoek

2017-12-01

Fire hazard is the disaster that always has an unpredictable process of coming. When it comes, its level scope and the magnitude of the effects cannot be predicted. Dense settlements especially in big cities, among others Bustaman Kampong Semarang never escape from physical problems such as flooding and wildfire. If both are compared in dense settlements scope, so that, wild fire is the most potentially catastrophic. It is necessary to do a research on passive fire protection in a village of high density city such as Bustaman. Qualitative research was conducted using descriptive method to conduct observations and interviews in the Bustaman. Bustaman as a high density village, with narrow roads and dense rows of houses. The terraced buildings are also encountered, and found many buildings use combustible material. That environmental conditions can facilitate the propagation of flames in case of fire. To improve the established Bustaman's environment, in terms of the application of passive fire protection systems, it is recommended to utilize the road as the dividing buildings. Need to build the separation wall fireproof in every each series in several units of too long buildings and attempted open space procurement that separates rows of buildings that are too long, and also the replacement of combustible material with a material that is more incombustible.

46 CFR 108.499 - Fire axes.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire axes. 108.499 Section 108.499 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Miscellaneous Firefighting Equipment § 108.499 Fire axes. Each unit must have at least two...

A Fire Severity Mapping System (FSMS) for real-time management applications and long term planning: Developing a map of the landscape potential for severe fire in the western United States

Treesearch

Gregory K. Dillon; Zachary A. Holden; Penny Morgan; Bob Keane

2009-01-01

The Fire Severity Mapping System project is geared toward providing fire managers across the western United States with critical information for dealing with and planning for the ecological effects of wildfire at multiple levels of thematic, spatial, and temporal detail. For this project, we are developing a comprehensive, west-wide map of the landscape potential for...

Unit 5, STA. 50+00+RB, retaining wall at First U.M. Churchdetail ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Unit 5, STA. 50+00+RB, retaining wall at First U.M. Church-detail - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA

Fire episodes in the Inland Northwest (1540-1940) based on fire history data

Treesearch

Stephen W. Barrett; Stephen F. Arno; James P. Menakis

1997-01-01

Presents maps of major fire episodes in the inland northwestern United States between 1540 and 1940 based on a compilation of fire history studies. Estimates annual acreage historically burned in this region and compares that with recent fire years.

Modern fire regime resembles historical fire regime in a ponderosa pine forest on Native American land

Treesearch

Amanda B. Stan; Peter Z. Fule; Kathryn B. Ireland; Jamie S. Sanderlin

2014-01-01

Forests on tribal lands in the western United States have seen the return of low-intensity surface fires for several decades longer than forests on non-tribal lands. We examined the surface fire regime in a ponderosa pinedominated (Pinus ponderosa) forest on the Hualapai tribal lands in the south-western United States. Using fire-scarred trees, we inferred temporal (...

Fire history, related to climate and land use in three southern Appalachian landscapes in the eastern United States.

PubMed

Flatley, William T; Lafon, Charles W; Grissino-Mayer, Henri D; LaForest, Lisa B

2013-09-01

Fire-maintained ecosystems and associated species are becoming increasingly rare in the southern Appalachian Mountains because of fire suppression policies implemented in the early 20th century. Restoration of these communities through prescribed fire has been hindered by a lack of information on historical fire regimes. To characterize past fire regimes, we collected and absolutely dated the tree rings on cross sections from 242 fire-scarred trees at three different sites in the southern Appalachian Mountains of Tennessee and North Carolina. Our objectives were to (1) characterize the historical frequency of fire in southern Appalachian mixed pine-oak forests, (2) assess the impact of interannual climatic variability on the historical occurrence of fire, and (3) determine whether changes in human culture and land use altered the frequency of fire. Results demonstrate that fires burned frequently at all three sites for at least two centuries prior to the implementation of fire suppression and prevention in the early to mid 20th century. Composite mean fire return intervals were 2-4 yr, and point mean fire return intervals were 9-13 yr. Area-wide fires that burned across multiple stands occurred at 6-13-yr intervals. The majority of fires were recorded during the dormant season. Fire occurrence exhibited little relationship with reconstructed annual drought conditions. Also, fire activity did not change markedly during the transition from Native American to Euro-American settlement or during the period of industrial logging at the start of the 20th century. Fire activity declined significantly, however, during the fire suppression period, with a nearly complete absence of fire during recent decades. The characterization of past fire regimes should provide managers with specific targets for restoration of fire-associated communities in the southern Appalachian Mountains. The fire chronologies reported here are among the longest tree-ring reconstructions of fire

Human Health Impacts of Forest Fires in the Southern United States: A Literature Review

Treesearch

Cynthia T. Fowler

2003-01-01

Forestry management practices can shape patterns of health, illness, and disease. A primary goal for owners federal, state, andprivate forests is to crap ecosystem management plans that simultaneously optimize forest health and human health. Fire-a major forest management issue in the United States-complicates these goals. Wildfires are natural phenomena with...

Fire Resistant Materials

NASA Technical Reports Server (NTRS)

1982-01-01

Fire hazard is greater in atmospheres containing a high percentage of oxygen under pressure. NASA intensified its fire safety research after a 1967 Apollo fire. A chemically treated fabric called Durette developed by Monsanto Company, which will not burn or produce noxious fumes, was selected as a material for Apollo astronaut garments. Monsanto sold production rights for this material to Fire Safe Products (FSP). Durette is now used for a wide range of applications such as: sheets, attendants' uniforms in hyperbaric chambers; crew's clothing, furniture and interior walls of diving chambers operated by the U.S. Navy and other oceanographic companies and research organizations. Pyrotect Safety Equipment, Minneapolis, MN produces Durette suits for auto racers, refuelers and crew chiefs from material supplied by FSP. FSP also manufactures Durette bags for filtering gases and dust from boilers, electric generators and similar systems. Durette bags are an alternative to other felted fiber capable of operating at high temperature that cost twice as much.

Firing system modification to alter ash properties for reduction of deposition and slagging under low NOx firing conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, D.; Lewis, R.; Tobiasz, R.

1998-12-31

The composition and properties of ash formed during coal firing have a major impact on boiler performance. Higher ash content in the coal can mean higher costs associated with coal handling, transportation, ash removal and ash disposal along with higher costs due to the increased ash content`s deleterious effects on pulverizing, combustion and heat transfer. ABB C-E Services, Inc. has conducted research for many years on what might be done to minimize the adverse effects of ash on boiler performance. Recently, ABB C-E Services has studied the effects of firing system modifications on ash composition and properties and the effectmore » these firing system modifications have on overall furnace performance. The subject of this paper is the impact of the installation of the CFS Concentric Firing System on the propensity for boiler wall ash deposition. For this study, CFS yaw angles were varied and particle samples were collected at the waterwalls for the different yaw angles tested. These ash samples were analyzed for ash composition. The results showed that with a larger CFS yaw angle (the air stream directed more towards the boiler walls) the base/acid ratio, iron content and sulfur content of the particle samples collected at the waterwall were reduced. This effect is due to several contributing factors: (1) an oxidizing environment produced by injecting more air toward the walls; and (2) an aerodynamic change which impacts the particle combustion time/temperature history.« less

Fire patterns in piñon and juniper land cover types in the Semiarid Western United States from 1984 through 2013

Treesearch

David I. Board; Jeanne C. Chambers; Richard F. Miller; Peter J. Weisberg

2018-01-01

Increases in area burned and fire size have been reported across a wide range of forest and shrubland types in the Western United States in recent decades, but little is known about potential changes in fire regimes of piñon and juniper land cover types. We evaluated spatio-temporal patterns of fire in piñon and juniper land cover types from the National Gap Analysis...

Enhancing fire science exchange: The Joint Fire Science Program's National Network of Knowledge Exchange Consortia

Treesearch

Vita Wright; Crystal Kolden; Todd Kipfer; Kristine Lee; Adrian Leighton; Jim Riddering; Leana Schelvan

2011-01-01

The Northern Rocky Mountain region is one of the most fire-prone regions in the United States. With a history of large fires that have shaped national policy, including the fires of 1910 and 2000 in Idaho and Montana and the Yellowstone fires of 1988, this region is projected to have many large severe fires in the future. Communication about fire science needs and...

Developing fire management mixes for fire program planning

Treesearch

Armando González-Cabán; Patricia B. Shinkle; Thomas J. Mills

1986-01-01

Evaluating economic efficiency of fire management program options requires information on the firefighting inputs, such as vehicles and crews, that would be needed to execute the program option selected. An algorithm was developed to translate automatically dollars allocated to type of firefighting inputs to numbers of units, using a set of weights for a specific fire...

Direct and indirect effects of climate change on projected future fire regimes in the western United States.

PubMed

Liu, Zhihua; Wimberly, Michael C

2016-01-15

We asked two research questions: (1) What are the relative effects of climate change and climate-driven vegetation shifts on different components of future fire regimes? (2) How does incorporating climate-driven vegetation change into future fire regime projections alter the results compared to projections based only on direct climate effects? We used the western United States (US) as study area to answer these questions. Future (2071-2100) fire regimes were projected using statistical models to predict spatial patterns of occurrence, size and spread for large fires (>400 ha) and a simulation experiment was conducted to compare the direct climatic effects and the indirect effects of climate-driven vegetation change on fire regimes. Results showed that vegetation change amplified climate-driven increases in fire frequency and size and had a larger overall effect on future total burned area in the western US than direct climate effects. Vegetation shifts, which were highly sensitive to precipitation pattern changes, were also a strong determinant of the future spatial pattern of burn rates and had different effects on fire in currently forested and grass/shrub areas. Our results showed that climate-driven vegetation change can exert strong localized effects on fire occurrence and size, which in turn drive regional changes in fire regimes. The effects of vegetation change for projections of the geographic patterns of future fire regimes may be at least as important as the direct effects of climate change, emphasizing that accounting for changing vegetation patterns in models of future climate-fire relationships is necessary to provide accurate projections at continental to global scales. Copyright © 2015 Elsevier B.V. All rights reserved.

Light, Compact Pumper for Harbor Fires

NASA Technical Reports Server (NTRS)

Burns, R. A.

1983-01-01

Report describes development of new transportable water-pumping unit for fire-fighting. Compact, self-contained unit provides fire protection at coastal and inland ports and is lighter than standard firetruck pumper of same capacity. Used to fight fires in harbors, cities, forests, refineries, chemical plants, and offshore drilling platforms. Other possible applications include cleaning up oilspills, pumping out ships, and flood control pumping.

Wildland fire: Nature’s fuel treatment

Treesearch

Brian Cooke; Sean Parks; Carol Miller; Lisa Holsinger; Cara Nelson; Zack Holden; Scott Baggett; Benjamin Bird

2016-01-01

Every year wildland fires affect much more acreage in the United States compared to controlled burns. Like controlled burns, wildland fire can help promote biological diversity and healthy ecosystems. But despite these facts, wildland fire is not often considered as a fuel treatment in the United States. Scientists working with the U.S. Forest Service’s Rocky Mountain...

A new forest fire paradigm: The need for high-severity fires

Treesearch

Monica L. Bond; Rodney B. Siegel; Richard L. Hutto; Victoria A. Saab; Stephen A. Shunk

2012-01-01

Bond, Monica L.; Siegel, Rodney B.; Hutto, Richard L.; Saab, Victoria A.; Shunk, Stephen A. 2012. A new forest fire paradigm: The need for high-severity fires. The Wildlife Professional. Winter 2012: 46-49. During the 2012 fire season from June through August, wildfires in the drought-stricken western and central United States burned more than 3.6 million acres of...

Restoring surface fire stabilizes forest carbon under extreme fire weather in the Sierra Nevada

Treesearch

Daniel J. Krofcheck; Matthew D. Hurteau; Robert M. Scheller; E. Louise Loudermilk

2017-01-01

Climate change in the western United States has increased the frequency of extreme fire weather events and is projected to increase the area burned by wildfire in the coming decades. This changing fire regime, coupled with increased high-severity fire risk from a legacy of fire exclusion, could destabilize forest carbon (C), decrease net ecosystem exchange (...

Climatic stress increases forest fire severity across the western United States

USGS Publications Warehouse

van Mantgem, Philip J.; Nesmith, Jonathan C. B.; Keifer, MaryBeth; Knapp, Eric E.; Flint, Alan; Flint, Lorraine

2013-01-01

Pervasive warming can lead to chronic stress on forest trees, which may contribute to mortality resulting from fire-caused injuries. Longitudinal analyses of forest plots from across the western US show that high pre-fire climatic water deficit was related to increased post-fire tree mortality probabilities. This relationship between climate and fire was present after accounting for fire defences and injuries, and appeared to influence the effects of crown and stem injuries. Climate and fire interactions did not vary substantially across geographical regions, major genera and tree sizes. Our findings support recent physiological evidence showing that both drought and heating from fire can impair xylem conductivity. Warming trends have been linked to increasing probabilities of severe fire weather and fire spread; our results suggest that warming may also increase forest fire severity (the number of trees killed) independent of fire intensity (the amount of heat released during a fire).

Land surveys show regional variability of historical fire regimes and dry forest structure of the western United States.

PubMed

Baker, William L; Williams, Mark A

2018-03-01

An understanding of how historical fire and structure in dry forests (ponderosa pine, dry mixed conifer) varied across the western United States remains incomplete. Yet, fire strongly affects ecosystem services, and forest restoration programs are underway. We used General Land Office survey reconstructions from the late 1800s across 11 landscapes covering ~1.9 million ha in four states to analyze spatial variation in fire regimes and forest structure. We first synthesized the state of validation of our methods using 20 modern validations, 53 historical cross-validations, and corroborating evidence. These show our method creates accurate reconstructions with low errors. One independent modern test reported high error, but did not replicate our method and made many calculation errors. Using reconstructed parameters of historical fire regimes and forest structure from our validated methods, forests were found to be non-uniform across the 11 landscapes, but grouped together in three geographical areas. Each had a mixture of fire severities, but dominated by low-severity fire and low median tree density in Arizona, mixed-severity fire and intermediate to high median tree density in Oregon-California, and high-severity fire and intermediate median tree density in Colorado. Programs to restore fire and forest structure could benefit from regional frameworks, rather than one size fits all. © 2018 by the Ecological Society of America.

Observing The Dynamics Of Wildland Grass Fires: FireFlux -A Field Validation Experiment

Treesearch

Craig B. Clements; Shiyuan Zhong; Scott Goodrick; Ju Li; Xindi Bian; Warren E. Heilman; Joseph J. Charney; Ryan Perna; Meongdo Jang; Daegyun Lee; Monica Patel; Susan Street; Glenn Aumann

2007-01-01

Grass fires, although not as intense as forest fires, present a major threat to life and property during periods of drought in the Great Plains of the United States. Recently, major wildland grass fires in Texas burned nearly 1.6 million acres and destroyed over 730 homes and 1320 other buildings. The fires resulted in the death of 19 people, an estimated loss of 10,...

An improved algorithm for small and cool fire detection using MODIS data: A preliminary study in the southeastern United States

Treesearch

Wanting Wang; John J. Qu; Xianjun Hao; Yongqiang Liu; William T. Sommers

2006-01-01

Traditional fire detection algorithms mainly rely on hot spot detection using thermal infrared (TIR) channels with fixed or contextual thresholds. Three solar reflectance channels (0.65 μm, 0.86 μm, and 2.1 μm) were recently adopted into the MODIS version 4 contextual algorithm to improve the active fire detection. In the southeastern United...

Designing fire safe interiors.

PubMed

Belles, D W

1992-01-01

Any product that causes a fire to grow large is deficient in fire safety performance. A large fire in any building represents a serious hazard. Multiple-death fires almost always are linked to fires that grow quickly to a large size. Interior finishes have large, continuous surfaces over which fire can spread. They are regulated to slow initial fire growth, and must be qualified for use on the basis of fire tests. To obtain meaningful results, specimens must be representative of actual installation. Variables--such as the substrate, the adhesive, and product thickness and density--can affect product performance. The tunnel test may not adequately evaluate some products, such as foam plastics or textile wall coverings, thermoplastic materials, or materials of minimal mass. Where questions exist, products should be evaluated on a full-scale basis. Curtains and draperies are examples of products that ignite easily and spread flames readily. The present method for testing curtains and draperies evaluates one fabric at a time. Although a fabric tested alone may perform well, fabrics that meet test standards individually sometimes perform poorly when tested in combination. Contents and furnishings constitute the major fuels in many fires. Contents may involve paper products and other lightweight materials that are easily ignited and capable of fast fire growth. Similarly, a small source may ignite many items of furniture that are capable of sustained fire growth. Upholstered furniture can reach peak burning rates in less than 5 minutes. Furnishings have been associated with many multiple-death fires.(ABSTRACT TRUNCATED AT 250 WORDS)

Variability of wildland fire emissions across the contiguous United States

Treesearch

YongQiang Liu

2004-01-01

This study analyzes spatial and temporal variability of emissions from wildland fires across the contiguous US. The emissions are estimates based on a recently constructed dataset of historical fire records collected by multiple US governlnental agencies. Both wildfire and prescribed fires have the highest emissions over the Pacific coastal states. Prescribed fire...

Developing standardized strategic response categories for fire management units

Treesearch

Matthew P. Thompson; Crystal S. Stonesifer; Robert C. Seli; Marlena Hovorka

2013-01-01

Federal wildland fire policy requires that publicly owned lands with burnable vegetation have a fire management plan (FMP); this applies to the five primary Federal fire agencies (Bureau of Indian Affairs, Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service, and Forest Service). FMPs are based on land and resource management plans and are...

Climatic stress increases forest fire severity across the western United States.

PubMed

van Mantgem, Phillip J; Nesmith, Jonathan C B; Keifer, MaryBeth; Knapp, Eric E; Flint, Alan; Flint, Lorriane

2013-09-01

Pervasive warming can lead to chronic stress on forest trees, which may contribute to mortality resulting from fire-caused injuries. Longitudinal analyses of forest plots from across the western US show that high pre-fire climatic water deficit was related to increased post-fire tree mortality probabilities. This relationship between climate and fire was present after accounting for fire defences and injuries, and appeared to influence the effects of crown and stem injuries. Climate and fire interactions did not vary substantially across geographical regions, major genera and tree sizes. Our findings support recent physiological evidence showing that both drought and heating from fire can impair xylem conductivity. Warming trends have been linked to increasing probabilities of severe fire weather and fire spread; our results suggest that warming may also increase forest fire severity (the number of trees killed) independent of fire intensity (the amount of heat released during a fire). Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Hip position and sex differences in motor unit firing patterns of the vastus medialis and vastus medialis oblique in healthy individuals.

PubMed

Peng, Yi-Ling; Tenan, Matthew S; Griffin, Lisa

2018-06-01

Weakness of the vastus medialis oblique (VMO) has been proposed to explain the high prevalence of knee pain in female subjects. Clinicians commonly use exercises in an attempt to preferentially activate the VMO. Recently, our group found evidence to support clinical theory that the VMO is neurologically distinct from the vastus medialis (VM). However, the ability to voluntarily activate these muscle subsections is still disputed. The aim of this study was to determine if VM and VMO activation varies between sexes and if control of the two muscles is different between rehabilitation exercises. Thirteen men and 13 women performed isometric straight leg raises in two hip positions, neutral hip rotation and 30 degrees lateral hip rotation. Bipolar intramuscular fine-wire electrodes were inserted into the VM and VMO to obtain motor unit recruitment thresholds and initial firing rates at recruitment. Linear mixed models and Tukey post hoc tests were used to assess significant differences in 654 motor units. Women demonstrated faster motor unit firing rate at recruitment, 1.18 ± 0.56 Hz higher than men. Motor units fired 0.47 ± 0.19 Hz faster during neutral hip rotation compared with lateral hip rotation. The VMO motor units were recruited 2.92 ± 1.28% earlier than the VM. All motor units were recruited 3.74 ± 1.27% earlier during neutral hip rotation than lateral hip rotation. Thus the VM and the VMO can be activated differentially, and their motor unit recruitment properties are affected by sex and hip position. NEW & NOTEWORTHY This is the first study to reveal differential activation of the vastus medialis oblique from the vastus medialis in clinical exercise protocols. Our research group used fine-wire electrodes to examine EMG signals of the vastus medialis oblique and vastus medialis to avoid possible cross talk. We also consider the effect of sex on motor unit firing patterns because of higher prevalence of knee pain in women, and yet few

Modeling regional-scale wildland fire emissions with the wildland fire emissions information system

Treesearch

Nancy H.F. French; Donald McKenzie; Tyler Erickson; Benjamin Koziol; Michael Billmire; K. Endsley; Naomi K.Y. Scheinerman; Liza Jenkins; Mary E. Miller; Roger Ottmar; Susan Prichard

2014-01-01

As carbon modeling tools become more comprehensive, spatial data are needed to improve quantitative maps of carbon emissions from fire. The Wildland Fire Emissions Information System (WFEIS) provides mapped estimates of carbon emissions from historical forest fires in the United States through a web browser. WFEIS improves access to data and provides a consistent...

40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... wall-fired boiler (other than units applying cell burner technology) shall not discharge, or allow to... input on an annual average basis for tangentially fired boilers. (2) 0.50 lb/mmBtu of heat input on an annual average basis for dry bottom wall-fired boilers (other than units applying cell burner technology...

Changing research needs in wilderness fire

Treesearch

Carol Miller

2008-01-01

Wilderness policies of the four agencies that manage wilderness in the United States recognize the importance of fire as a natural process and federal fire policy supports allowing lightning-caused fires to burn. However, a complex suite of challenges has limited the restoration and maintenance of natural fire regimes in wilderness (Parsons 2000). As a result, fire...

Exposure of a liquefied gas container to an external fire.

PubMed

Raj, Phani K

2005-06-30

In liquefied gas, bulk-storage facilities and plants, the separation distances between storage tanks and between a tank and a line of adjoining property that can be built are governed by local regulations and/or codes (e.g. National Fire Protection Association (NFPA) 58, 2004). Separation distance requirements have been in the NFPA 58 Code for over 60 years; however, no scientific foundations (either theoretical or experimental) are available for the specified distances. Even though the liquefied petroleum gas (LPG) industry has operated safely over the years, there is a question as to whether the code-specified distances provide sufficient safety to LPG-storage tanks, when they are exposed to large external fires. A radiation heat-transfer-based model is presented in this paper. The temporal variation of the vapor-wetted tank-wall temperature is calculated when exposed to thermal radiation from an external, non-impinging, large, 30.5 m (100 ft) diameter, highly radiative, hydrocarbon fuel (pool) fire located at a specified distance. Structural steel wall of a pressurized, liquefied gas container (such as the ASME LP-Gas tank) begins to lose its strength, when the wall temperature approaches a critical temperature, 810 K (1000 degrees F). LP-Gas tank walls reaching close to this temperature will be a cause for major concern because of increased potential for tank failure, which could result in catastrophic consequences. Results from the model for exposure of different size ASME (LP-Gas) containers to a hydrocarbon pool fire of 30.5 m (100 ft) in diameter, located with its base edge at the separation distances specified by NFPA 58 [NFPA 58, Liquefied Petroleum Gas Code, Table 6.3.1, 2004 ed., National Fire Protection Association, Quincy, MA, 2004] indicate that the vapor-wetted wall temperature of the containers never reach the critical temperature under common wind conditions (0, 5 and 10 m/s), with the flame tilting towards the tank. This indicates that the

46 CFR 108.419 - Fire main capacity.

Code of Federal Regulations, 2011 CFR

2011-10-01

... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.419 Fire main capacity. The diameter of the fire... pumps operating simultaneously. ...

46 CFR 108.419 - Fire main capacity.

Code of Federal Regulations, 2010 CFR

2010-10-01

... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.419 Fire main capacity. The diameter of the fire... pumps operating simultaneously. ...

Annotated bibliography of fire literature relative to northern grasslands in south-central Canada and north-central United States

USGS Publications Warehouse

Higgins, Kenneth F.; Fellows, David P.; Callow, J. Mike; Kruse, Arnold D.; Piehl, James L.

1989-01-01

Natural resource managers have greatly increased the use of fire to manage grassland habitats during the past two decades in the northern Great Plains region of the United States and Canada. In support of these efforts, we have compiled this annotated bibliography to provide a condensed reference of fire literature for those managers with an interest in fire ecology. References are arranged alphabetically by author and year, numbered consecutively, and referenced by number in the author and subject indexes that follow the bibliography. The intent in compiling the bibliography and indexes is more to identify subject matter and to direct the reader to sources rather than to provide a digested interpretation of each manuscript.

8. BUILDING 313, INTERIOR, EAST WALL OF EASTERN STOREROOM, LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. BUILDING 313, INTERIOR, EAST WALL OF EASTERN STOREROOM, LOOKING NORTHEAST, WITH TIME CLOCK AND FIRE SPRINKLER CONTROLS ON WALL, AND ENTRY TO OFFICE AREA AT LEFT. - Oakland Naval Supply Center, General Storehouses, Between Third & Fourth Streets, North of A Street, Oakland, Alameda County, CA

29. Interior view, south end of the west (front) wall ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. Interior view, south end of the west (front) wall looking at the section between the door and southwestern corner, with scale (note remnants of the post-1915 fire plaster on wall) - Kiskiack, Naval Mine Depot, State Route 238 vicinity, Yorktown, York County, VA

Resolving vorticity-driven lateral fire spread using the WRF-Fire coupled atmosphere-fire numerical model

NASA Astrophysics Data System (ADS)

Simpson, C. C.; Sharples, J. J.; Evans, J. P.

2014-05-01

Fire channelling is a form of dynamic fire behaviour, during which a wildland fire spreads rapidly across a steep lee-facing slope in a direction transverse to the background winds, and is often accompanied by a downwind extension of the active flaming region and extreme pyro-convection. Recent work using the WRF-Fire coupled atmosphere-fire model has demonstrated that fire channelling can be characterised as vorticity-driven lateral fire spread (VDLS). In this study, 16 simulations are conducted using WRF-Fire to examine the sensitivity of resolving VDLS to spatial resolution and atmosphere-fire coupling within the WRF-Fire model framework. The horizontal grid spacing is varied between 25 and 90 m, and the two-way atmosphere-fire coupling is either enabled or disabled. At high spatial resolution, the atmosphere-fire coupling increases the peak uphill and lateral spread rate by a factor of up to 2.7 and 9.5. The enhancement of the uphill and lateral spread rate diminishes at coarser spatial resolution, and VDLS is not modelled for a horizontal grid spacing of 90 m. The laterally spreading fire fronts become the dominant contributors of the extreme pyro-convection. The resolved fire-induced vortices responsible for driving the lateral spread in the coupled simulations have non-zero vorticity along each unit vector direction, and develop due to an interaction between the background winds and vertical return circulations generated at the flank of the fire front as part of the pyro-convective updraft. The results presented in this study demonstrate that both high spatial resolution and two-way atmosphere-fire coupling are required to reproduce VDLS within the current WRF-Fire model framework.

Lightning fires in southwestern forests

Treesearch

Jack S. Barrows

1978-01-01

Lightning is the leading cause of fires in southwestern forests. On all protected private, state and federal lands in Arizona and New Mexico, nearly 80 percent of the forest, brush and range fires are ignited by lightning. The Southwestern region leads all other regions of the United States both in total number of lightning fires and in the area burned by these fires...

Simulation of one-sided heating of boiler unit membrane-type water walls

NASA Astrophysics Data System (ADS)

Kurepin, M. P.; Serbinovskiy, M. Yu.

2017-03-01

This study describes the results of simulation of the temperature field and the stress-strain state of membrane-type gastight water walls of boiler units using the finite element method. The methods of analytical and standard calculation of one-sided heating of fin-tube water walls by a radiative heat flux are analyzed. The methods and software for input data calculation in the finite-element simulation, including thermoelastic moments in welded panels that result from their one-sided heating, are proposed. The method and software modules are used for water wall simulation using ANSYS. The results of simulation of the temperature field, stress field, deformations and displacement of the membrane-type panel for the boiler furnace water wall using the finite-element method, as well as the results of calculation of the panel tube temperature, stresses and deformations using the known methods, are presented. The comparison of the known experimental results on heating and bending by given moments of membrane-type water walls and numerical simulations is performed. It is demonstrated that numerical results agree with high accuracy with the experimental data. The relative temperature difference does not exceed 1%. The relative difference of the experimental fin mutual turning angle caused by one-sided heating by radiative heat flux and the results obtained in the finite element simulation does not exceed 8.5% for nondisplaced fins and 7% for fins with displacement. The same difference for the theoretical results and the simulation using the finite-element method does not exceed 3% and 7.1%, respectively. The proposed method and software modules for simulation of the temperature field and stress-strain state of the water walls are verified and the feasibility of their application in practical design is proven.

Effectiveness of Fire and Fire Surrogate Treatments For Controlling Wildfire Behavior in Piedmont Forests: A Simulation Study

Treesearch

Helen H. Mohr; Thomas A. Waldrop; Sandra Rideout; Ross J. Phillips; Charles T. Flint

2004-01-01

The need for fuel reduction has increased in United States forests due to decades of fire exclusion. Excessive fuel buildup has led to uncharacteristically severe fires in areas with historically short-interval, low-to-moderate-intensity fire regimes. The National Fire and Fire Surrogate (NFFS) Study compared the impacts of three fuel-reduction treatments on numerous...

Fire and birds in the southwestern United States

Treesearch

Carl E. Bock; William M. Block

2005-01-01

Fire is an important ecological force in many southwestern ecosystems, but frequencies, sizes, and intensities of fire have been altered historically by grazing, logging, exotic vegetation, and suppression. Prescribed burning should be applied widely, but under experimental conditions that facilitate studying its impacts on birds and other components of biodiversity....

Fighting fire in the heat of the day: An analysis of operational and environmental conditions of use for large airtankers in United States fire suppression

Treesearch

Crystal S. Stonesifer; Dave Calkin; Matthew P. Thompson; Keith D. Stockmann

2016-01-01

Large airtanker use is widespread in wildfire suppression in the United States. The current approach to nationally dispatching the fleet of federal contract airtankers relies on filling requests for airtankers to achieve suppression objectives identified by fire managers at the incident level. In general, demand is met if resources are available, and the...

Dow's fire and explosion index: a case-study in the process unit of an oil extraction factory.

PubMed

Nezamodini, Zeynab Sadat; Rezvani, Zahra; Kian, Kumars

2017-02-01

The incidence of fires and explosions have led to severe damage in many industries, primarily in industries' financial losses. This study was conducted to estimate losses due to fire and explosion and the impact of control measures on the number of losses applying Dow's Fire and Explosion Index. This is a case study conducted in one of the process units of an oil extraction factory. Dow's Fire and Explosion Index Hazard classification guide, 7 th edition, issued by the American Institute of Chemical Engineers was applied. Data were obtained mainly through interviews and consultation with experts, as well as reported operating parameters and process documents. The Dow Index of the processing unit was estimated to be 243.68, and the most probable base damage was approximately $4.15 million in 2008. The actual damages were estimated to be $2,863,500, and the number of lost work days to be 64.56 days. The interruption losses were estimated to be $15,817,200 and the total losses to the system to be $18.67 million. These results demonstrated that losses resulting from production interruptions are greater than losses due to the destruction of equipment. A series of corrections was then proposed and risk analysis was performed again to examine the effects of reforms. The comparison shows that by applying reforms the FEI can change to 86.62 and the total loss can reduce to $9.03 million. This study shows that Dow's Index is a systematic tool to examine the impact of control measures. It also enhances resource management considering an optimal insurance contract. Considering the priority of reducing damage factors, several correction actions were suggested, such as modifying the drainage system, installation of hexane detectors, an automatic sprinkler system, fire detectors on the cable tray, and finally, using the water spray washing on the tanks.

Summaries of BFRL fire research in-house projects and grants, 1993

NASA Astrophysics Data System (ADS)

Jason, Nora H.

1993-09-01

The report describes the fire research projects performed in the Building and Fire Research Laboratory (BFRL) and under its extramural grants program during fiscal year 1993. The BFRL Fire Research Program has directed its efforts under three program thrusts. The in-house priority projects, grants, and externally-funded efforts thus form an integrated, focussed ensemble. The publication is organized along those lines: fire risk and hazard prediction - carbon monoxide prediction, turbulent combustion, soot, engineering analysis, fire hazard assessment, and large fires; fire safety of products and materials - materials combustion, furniture flammability, and wall and ceiling fires; and advanced technologies for fire sensing and control - fire detection and fire suppression. For the convenience of the reader, an alphabetical listing of all grants is contained in Part 2.0.

Quantifying the multi-scale response of avifauna to prescribed fire experiments in the southwest United States

Treesearch

Brett G. Dickson; Barry R. Noon; Curtis H. Flather; Stephanie Jentsch; William M. Block

2009-01-01

Landscape-scale disturbance events, including ecological restoration and fuel reduction activities, can modify habitat and affect relationships between species and their environment. To reduce the risk of uncharacteristic stand-replacing fires in the southwestern United States, land managers are implementing restoration and fuels treatments (e.g., mechanical thinning,...

Modification of VanWagner's canopy fire propagation model

Treesearch

James Dickinson; Andrew Robinson; Richy Harrod; Paul Gessler; Alistair Smith

2007-01-01

The conditions necessary for the combustion of canopy fuels are not well known but are assumed to be highly influenced by the volume through which the canopy fuels are dispersed, known as canopy bulk density (CBD). Propagating crown fire is defined as a continuous wall of flame from the bottom to the top of the canopy, implying crown fire propagation is actually...

Development of aircraft lavatory compartments with improved fire resistance characteristics, phase 1: Fire containment test of a wide body aircraft lavatory module

NASA Technical Reports Server (NTRS)

Anderson, R. A.; Arnold, D. B.; Johnson, G. A.; Tustin, E. A.

1978-01-01

A test was conducted to evaluate the fire containment characteristics of a Boeing 747 lavatory module. Results showed that the fire was contained within the lavatory during the 30-minute test period with the door closed. The resistance of the lavatory wall and ceiling panels and general lavatory construction to burn-through under the test conditions was demonstrated.

Citizens in the Crosshairs: Ready, Aim, Hold Your Fire?

DTIC Science & Technology

2012-03-21

Citizens in the Crosshairs: Ready, Aim, Hold Your Fire ? by Colonel Ian G. Corey United States Army United States...SUBTITLE Citizens in the Crosshairs: Ready, Aim, Hold Your Fire ? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...YOUR FIRE ? by Colonel Ian G. Corey United States Army Professor Daniel Y. Coulter Project Adviser This SRP

Information processing in an urban fire department communication system.

PubMed

Siegel, J; Weitzman, D O

1975-09-01

One of the most important functions of any fire department is to provide selective contact with fire fighting units and to dispatch these units based on information gathered from street alarm boxes and telephones. This paper is concerned with the problem of dispatching tactical response information to remote fire fighting units and with the effect of workload on the dispatch function.

11. BUILDING 332, INTERIOR, WESTERN STOREROOM, FROM FIRE DOOR IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. BUILDING 332, INTERIOR, WESTERN STOREROOM, FROM FIRE DOOR IN EAST WALL, LOOKING WEST, WITH ENCLOSED OFFICE AREA (PHOTOS AA-7 &-8) BEYOND WALL ON RIGHT. - Oakland Naval Supply Center, Dry Provisions Storehouses, Between Third & Fourth Streets, Between G & L Street, Oakland, Alameda County, CA

Estimating suppression expenditures for individual large wildland fires

Treesearch

Krista M. Gebert; David E. Calkin; Jonathan Yoder

2007-01-01

The extreme cost of fighting wildland fires has brought fire suppression expenditures to the forefront of budgetary and policy debate in the United States. Inasmuch as large fires are responsible for the bulk of fire suppression expenditures, understanding fire characteristics that influence expenditures is important for both strategic fire planning and onsite fire...

High-severity fire: evaluating its key drivers and mapping its probability across western US forests

NASA Astrophysics Data System (ADS)

Parks, Sean A.; Holsinger, Lisa M.; Panunto, Matthew H.; Jolly, W. Matt; Dobrowski, Solomon Z.; Dillon, Gregory K.

2018-04-01

Wildland fire is a critical process in forests of the western United States (US). Variation in fire behavior, which is heavily influenced by fuel loading, terrain, weather, and vegetation type, leads to heterogeneity in fire severity across landscapes. The relative influence of these factors in driving fire severity, however, is poorly understood. Here, we explore the drivers of high-severity fire for forested ecoregions in the western US over the period 2002–2015. Fire severity was quantified using a satellite-inferred index of severity, the relativized burn ratio. For each ecoregion, we used boosted regression trees to model high-severity fire as a function of live fuel, topography, climate, and fire weather. We found that live fuel, on average, was the most important factor driving high-severity fire among ecoregions (average relative influence = 53.1%) and was the most important factor in 14 of 19 ecoregions. Fire weather was the second most important factor among ecoregions (average relative influence = 22.9%) and was the most important factor in five ecoregions. Climate (13.7%) and topography (10.3%) were less influential. We also predicted the probability of high-severity fire, were a fire to occur, using recent (2016) satellite imagery to characterize live fuel for a subset of ecoregions in which the model skill was deemed acceptable (n = 13). These ‘wall-to-wall’ gridded ecoregional maps provide relevant and up-to-date information for scientists and managers who are tasked with managing fuel and wildland fire. Lastly, we provide an example of the predicted likelihood of high-severity fire under moderate and extreme fire weather before and after fuel reduction treatments, thereby demonstrating how our framework and model predictions can potentially serve as a performance metric for land management agencies tasked with reducing hazardous fuel across large landscapes.

The use of fire in forest restoration

Treesearch

Colin C. Hardy; Stephen F. Arno

1996-01-01

The 26 papers in this document address the current knowledge of fire as a disturbance agent, fire history and fire regimes, applications of prescribed fire for ecological restoration, and the effects of fire on the various forested ecosystems of the north-western United States. The main body of this document is organized in three sections: Assessing Needs for Fire in...

40 CFR Appendix A to Part 76 - Phase I Affected Coal-Fired Utility Units With Group 1 or Cell Burner Boilers

Code of Federal Regulations, 2011 CFR

2011-07-01

... Units With Group 1 or Cell Burner Boilers A Appendix A to Part 76 Protection of Environment... 1 or Cell Burner Boilers Table 1—Phase I Tangentially Fired Units State Plant Unit Operator ALABAMA... TOWER 9 CEN ILLINOIS PUB SER. INDIANA CULLEY 2 STHERN IND GAS & EL. INDIANA CULLEY 3 STHERN IND GAS & EL...

Expected ozone benefits of reducing nitrogen oxide (NOx) emissions from coal-fired electricity generating units in the eastern United States.

PubMed

Vinciguerra, Timothy; Bull, Emily; Canty, Timothy; He, Hao; Zalewsky, Eric; Woodman, Michael; Aburn, George; Ehrman, Sheryl; Dickerson, Russell R

2017-03-01

On hot summer days in the eastern United States, electricity demand rises, mainly because of increased use of air conditioning. Power plants must provide this additional energy, emitting additional pollutants when meteorological conditions are primed for poor air quality. To evaluate the impact of summertime NO x emissions from coal-fired electricity generating units (EGUs) on surface ozone formation, we performed a series of sensitivity modeling forecast scenarios utilizing EPA 2018 version 6.0 emissions (2011 base year) and CMAQ v5.0.2. Coal-fired EGU NO x emissions were adjusted to match the lowest NO x rates observed during the ozone seasons (April 1-October 31) of 2005-2012 (Scenario A), where ozone decreased by 3-4 ppb in affected areas. When compared to the highest emissions rates during the same time period (Scenario B), ozone increased ∼4-7 ppb. NO x emission rates adjusted to match the observed rates from 2011 (Scenario C) increased ozone by ∼4-5 ppb. Finally in Scenario D, the impact of additional NO x reductions was determined by assuming installation of selective catalytic reduction (SCR) controls on all units lacking postcombustion controls; this decreased ozone by an additional 2-4 ppb relative to Scenario A. Following the announcement of a stricter 8-hour ozone standard, this analysis outlines a strategy that would help bring coastal areas in the mid-Atlantic region closer to attainment, and would also provide profound benefits for upwind states where most of the regional EGU NO x originates, even if additional capital investments are not made (Scenario A). With the 8-hr maximum ozone National Ambient Air Quality Standard (NAAQS) decreasing from 75 to 70 ppb, modeling results indicate that use of postcombustion controls on coal-fired power plants in 2018 could help keep regions in attainment. By operating already existing nitrogen oxide (NO x ) removal devices to their full potential, ozone could be significantly curtailed, achieving ozone

46 CFR 130.470 - Fire alarms.

Code of Federal Regulations, 2014 CFR

2014-10-01

... fire detector and control unit must be of a type specifically approved by the Commandant (CG-ENG). (b) No fire-alarm circuit for the engine room may contain a fire detector for any other space. (c) The number and placement of fire detectors must be approved by the cognizant OCMI. [CGD 82-004 and CGD 86-074...

46 CFR 130.470 - Fire alarms.

Code of Federal Regulations, 2011 CFR

2011-10-01

... fire detector and control unit must be of a type specifically approved by the Commandant (CG-521). (b) No fire-alarm circuit for the engine room may contain a fire detector for any other space. (c) The number and placement of fire detectors must be approved by the cognizant OCMI. [CGD 82-004 and CGD 86-074...

46 CFR 130.470 - Fire alarms.

Code of Federal Regulations, 2010 CFR

2010-10-01

... fire detector and control unit must be of a type specifically approved by the Commandant (CG-521). (b) No fire-alarm circuit for the engine room may contain a fire detector for any other space. (c) The number and placement of fire detectors must be approved by the cognizant OCMI. [CGD 82-004 and CGD 86-074...

46 CFR 130.470 - Fire alarms.

Code of Federal Regulations, 2013 CFR

2013-10-01

... fire detector and control unit must be of a type specifically approved by the Commandant (CG-ENG). (b) No fire-alarm circuit for the engine room may contain a fire detector for any other space. (c) The number and placement of fire detectors must be approved by the cognizant OCMI. [CGD 82-004 and CGD 86-074...

46 CFR 130.470 - Fire alarms.

Code of Federal Regulations, 2012 CFR

2012-10-01

... fire detector and control unit must be of a type specifically approved by the Commandant (CG-ENG). (b) No fire-alarm circuit for the engine room may contain a fire detector for any other space. (c) The number and placement of fire detectors must be approved by the cognizant OCMI. [CGD 82-004 and CGD 86-074...

Invasion Biology on Your Campus: Investigating the Red Imported Fire Ant in the Southeastern United States.

ERIC Educational Resources Information Center

Forys, Elizabeth A.; Kelly, William B.; Ward, David T.

2003-01-01

Describes a laboratory activity on invasion biology to improve students' cognitive skills as well as manual skills. Requires students to develop hypotheses in which a common invasive species will succeed. Focuses on the red imported fire ant in the Southeastern United States, which is a non-native invasive species. (Contains 17 references.) (YDS)

Fire and bark beetle interactions

Treesearch

Ken Gibson; Jose F. Negron

2009-01-01

Bark beetle populations are at outbreak conditions in many parts of the western United States and causing extensive tree mortality. Bark beetles interact with other disturbance agents in forest ecosystems, one of the primary being fires. In order to implement appropriate post-fire management of fire-damaged ecosystems, we need a better understanding of...

Interannual variations in fire weather, fire extent, and synoptic-scale circulation patterns in northern California and Oregon

Treesearch

Valerie Trouet; Alan H. Taylor; Andrew M. Carleton; Carl N. Skinner

2009-01-01

The Mediterranean climate region on the west coast of the United States is characterized by wet winters and dry summers, and by high fire activity. The importance of synoptic-scale circulation patterns (ENSO, PDO, PNA) on fire-climate interactions is evident in contemporary fire data sets and in pre-Euroamerican tree-ring-based fire records. We investigated how...

Impacts of prescribed fires on air quality over the Southeastern United States in spring based on modeling and ground/satellite measurements.

PubMed

Zeng, Tao; Wang, Yuhang; Yoshida, Yasuko; Tian, Di; Russell, Amistead G; Barnard, William R

2008-11-15

Prescribed burning is a large aerosol source in the southeastern United States. Its air quality impact is investigated using 3-D model simulations and analysis of ground and satellite observations. Fire emissions for 2002 are calculated based on a recently developed VISTAS emission inventory. March was selected for the investigation because it is the most active prescribed fire month. Inclusion of fire emissions significantly improved model performance. Model results show that prescribed fire emissions lead to approximately 50% enhancements of mean OC and EC concentrations in the Southeast and a daily increase of PM2.5 up to 25 microg m(-3), indicating that fire emissions can lead to PM2.5 nonattainment in affected regions. Surface enhancements of CO up to 200 ppbv are found. Fire count measurements from the moderate resolution imaging spectroradiometer (MODIS) onboard the NASA Terra satellite show large springtime burning in most states, which is consistent with the emission inventory. These measurements also indicate that the inventory may underestimate fire emissions in the summer.

Post-fire debris flow prediction in Western United States: Advancements based on a nonparametric statistical technique

NASA Astrophysics Data System (ADS)

Nikolopoulos, E. I.; Destro, E.; Bhuiyan, M. A. E.; Borga, M., Sr.; Anagnostou, E. N.

2017-12-01

Fire disasters affect modern societies at global scale inducing significant economic losses and human casualties. In addition to their direct impacts they have various adverse effects on hydrologic and geomorphologic processes of a region due to the tremendous alteration of the landscape characteristics (vegetation, soil properties etc). As a consequence, wildfires often initiate a cascade of hazards such as flash floods and debris flows that usually follow the occurrence of a wildfire thus magnifying the overall impact in a region. Post-fire debris flows (PFDF) is one such type of hazards frequently occurring in Western United States where wildfires are a common natural disaster. Prediction of PDFD is therefore of high importance in this region and over the last years a number of efforts from United States Geological Survey (USGS) and National Weather Service (NWS) have been focused on the development of early warning systems that will help mitigate PFDF risk. This work proposes a prediction framework that is based on a nonparametric statistical technique (random forests) that allows predicting the occurrence of PFDF at regional scale with a higher degree of accuracy than the commonly used approaches that are based on power-law thresholds and logistic regression procedures. The work presented is based on a recently released database from USGS that reports a total of 1500 storms that triggered and did not trigger PFDF in a number of fire affected catchments in Western United States. The database includes information on storm characteristics (duration, accumulation, max intensity etc) and other auxiliary information of land surface properties (soil erodibility index, local slope etc). Results show that the proposed model is able to achieve a satisfactory prediction accuracy (threat score > 0.6) superior of previously published prediction frameworks highlighting the potential of nonparametric statistical techniques for development of PFDF prediction systems.

31. Interior view, north end of the west wall looking ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. Interior view, north end of the west wall looking at the section between the front door and the northwestern corner of the building, with scale (note position of post fire partition wall and floor joists as recorded in the brickwork) - Kiskiack, Naval Mine Depot, State Route 238 vicinity, Yorktown, York County, VA

Multi-scalar influence of weather and climate on very large-fires in the Eastern United States

Treesearch

John T. Abatzoglou; Renaud Barbero; Crystal A. Kolden; Katherine C. Hegewisch; Narasimhan K. Larkin; Harry Podschwit

2014-01-01

A majority of area burned in the Eastern United States (EUS) results from a limited number of exceptionally large wildfires. Relationships between climatic conditions and the occurrence of very large-fires (VLF) in the EUS were examined using composite and climate-niche analyses that consider atmospheric factors across inter-annual, sub-seasonal and synoptic temporal...

Fire effects on noxious weeds

Treesearch

Robin Innes

2012-01-01

The Fire Effects Information System (FEIS, www.fs.fed.us/database/feis/) has been providing reviews of scientific knowledge about fire effects since 1986. FEIS is an online collection of literature reviews on more than 1,100 species and their relationships with fire. Reviews cover plants and animals throughout the United States, providing a wealth of information for...

Fire danger rating network density

Treesearch

Rudy M. King; R. William Furman

1976-01-01

Conventional statistical techniques are used to answer the question, "What is the necessary station density for a fire danger network?" The Burning Index of the National Fire-Danger Rating System is used as an indicator of fire danger. Results are presented as station spacing in tabular form for each of six regions in the western United States.

Measurements of forest fire danger

Treesearch

Leo Shames

1938-01-01

Although the annual destruction of life and property attributable to forest fires is enormous, scientific methods of forest fire control in the United States are of comparatively recent origin. In one important phase of control, that of determining how large a network of observers is necessary for the purpose of discovering forest fires in their infancy, accurate means...

46 CFR 108.405 - Fire detection system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Fire detection system. 108.405 Section 108.405 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.405 Fire detection system. (a) Each fire detection system and...

46 CFR 108.405 - Fire detection system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fire detection system. 108.405 Section 108.405 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.405 Fire detection system. (a) Each fire detection system and...

46 CFR 108.405 - Fire detection system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Fire detection system. 108.405 Section 108.405 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.405 Fire detection system. (a) Each fire detection system and...

46 CFR 108.405 - Fire detection system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Fire detection system. 108.405 Section 108.405 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.405 Fire detection system. (a) Each fire detection system and...

Climatic stress increases forest fire severity across the western United States

Treesearch

Phillip J. van Mantgem; Jonathan C.B. Nesmith; MaryBeth Keifer; Eric E. Knapp; Alan Flint; Lorriane Flint

2013-01-01

Pervasive warming can lead to chronic stress on forest trees, which may contribute to mortality resulting from fire-caused injuries. Longitudinal analyses of forest plots from across the western US show that high pre-fire climatic water deficit was related to increased post-fire tree mortality probabilities. This relationship between climate and fire was present after...

Quantifying the multi-scale response of avifauna to prescribed fire experiments in the southwest United States.

PubMed

Dickson, Brett G; Noon, Barry R; Flather, Curtis H; Jentsch, Stephanie; Block, William M

2009-04-01

Landscape-scale disturbance events, including ecological restoration and fuel reduction activities, can modify habitat and affect relationships between species and their environment. To reduce the risk of uncharacteristic stand-replacing fires in the southwestern United States, land managers are implementing restoration and fuels treatments (e.g., mechanical thinning, prescribed fire) in progressively larger stands of dry, lower elevation ponderosa pine (Pinus ponderosa) forest. We used a Before-After/Control-Impact experimental design to quantify the multi-scale response of avifauna to large (approximately 250-400 ha) prescribed fire treatments on four sites in Arizona and New Mexico dominated by ponderosa pine. Using distance sampling and an information-theoretic approach, we estimated changes in density for 14 bird species detected before (May-June 2002-2003) and after (May-June 2004-2005) prescribed fire treatments. We observed few site-level differences in pre- and posttreatment density, and no species responded strongly to treatment on all four sites. Point-level spatial models of individual species response to treatment, habitat variables, and fire severity revealed ecological relationships that were more easily interpreted. At this scale, pretreatment forest structure and patch characteristics were important predictors of posttreatment differences in bird species density. Five species (Pygmy Nuthatch [Sitta pygmaea], Western Bluebird [Sialia mexicana], Steller's Jay [Cyanocitta stelleri], American Robin [Turdus migratorius], and Hairy Woodpecker [Picoides villosus]) exhibited a strong treatment response, and two of these species (American Robin and Hairy Woodpecker) could be associated with meaningful fire severity response functions. The avifaunal response patterns that we observed were not always consistent with those reported by more common studies of wildland fire events. Our results suggest that, in the short-term, the distribution and abundance of

Motor units in vastus lateralis and in different vastus medialis regions show different firing properties during low-level, isometric knee extension contraction.

PubMed

de Souza, Leonardo Mendes Leal; Cabral, Hélio Veiga; de Oliveira, Liliam Fernandes; Vieira, Taian Martins

2018-04-01

Architectural differences along vastus medialis (VM) and between VM and vastus lateralis (VL) are considered functionally important for the patellar tracking, knee joint stability and knee joint extension. Whether these functional differences are associated with a differential activity of motor units between VM and VL is however unknown. In the present study, we, therefore, investigate neuroanatomical differences in the activity of motor units detected proximo-distally from VM and from the VL muscle. Nine healthy volunteers performed low-level isometric knee extension contractions (20% of their maximum voluntary contraction) following a trapezoidal trajectory. Surface electromyograms (EMGs) were recorded from VM proximal and distal regions and from VL using three linear adhesive arrays of eight electrodes. The firing rate and recruitment threshold of motor units decomposed from EMGs were then compared among muscle regions. Results show that VL motor units reached lower mean firing rates in comparison with VM motor units, regardless of their position within VM (P < .040). No significant differences in firing rate were found between proximal and distal, VM motor units (P = .997). Furthermore, no significant differences in the recruitment threshold were observed for all motor units analysed (P = .108). Our findings possibly suggest the greater potential of VL to generate force, due to its fibres arrangement, may account for the lower discharge rate observed for VL then either proximally or distally detected motor units in VM. Additionally, the present study opens new perspectives on the importance of considering muscle architecture in investigations of the neural aspects of motor behaviour. Copyright © 2017 Elsevier B.V. All rights reserved.

Inhibition linearizes firing rate responses in human motor units: implications for the role of persistent inward currents.

PubMed

Revill, Ann L; Fuglevand, Andrew J

2017-01-01

Motor neurons are the output neurons of the central nervous system and are responsible for controlling muscle contraction. When initially activated during voluntary contraction, firing rates of motor neurons increase steeply but then level out at modest rates. Activation of an intrinsic source of excitatory current at recruitment onset may underlie the initial steep increase in firing rate in motor neurons. We attempted to disable this intrinsic excitatory current by artificially activating an inhibitory reflex. When motor neuron activity was recorded while the inhibitory reflex was engaged, firing rates no longer increased steeply, suggesting that the intrinsic excitatory current was probably responsible for the initial sharp rise in motor neuron firing rate. During graded isometric contractions, motor unit (MU) firing rates increase steeply upon recruitment but then level off at modest rates even though muscle force continues to increase. The mechanisms underlying such firing behaviour are not known although activation of persistent inward currents (PICs) might be involved. PICs are intrinsic, voltage-dependent currents that activate strongly when motor neurons (MNs) are first recruited. Such activation might cause a sharp escalation in depolarizing current and underlie the steep initial rise in MU firing rate. Because PICs can be disabled with synaptic inhibition, we hypothesized that artificial activation of an inhibitory pathway might curb this initial steep rise in firing rate. To test this, human subjects performed slow triangular ramp contractions of the ankle dorsiflexors in the absence and presence of tonic synaptic inhibition delivered to tibialis anterior (TA) MNs by sural nerve stimulation. Firing rate profiles (expressed as a function of contraction force) of TA MUs recorded during these tasks were compared for control and stimulation conditions. Under control conditions, during the ascending phase of the triangular contractions, 93% of the firing

Fire characteristics associated with firefighter injury on large federal wildland fires.

PubMed

Britton, Carla; Lynch, Charles F; Torner, James; Peek-Asa, Corinne

2013-02-01

Wildland fires present many injury hazards to firefighters. We estimate injury rates and identify fire-related factors associated with injury. Data from the National Interagency Fire Center from 2003 to 2007 provided the number of injuries in which the firefighter could not return to his or her job assignment, person-days worked, and fire characteristics (year, region, season, cause, fuel type, resistance to control, and structures destroyed). We assessed fire-level risk factors of having at least one reported injury using logistic regression. Negative binomial regression was used to examine incidence rate ratios associated with fire-level risk factors. Of 867 fires, 9.5% required the most complex management and 24.7% required the next-highest level of management. Fires most often occurred in the western United States (82.8%), during the summer (69.6%), caused by lightening (54.9%). Timber was the most frequent fuel source (40.2%). Peak incident management level, person-days of exposure, and the fire's resistance to control were significantly related to the odds of a fire having at least one reported injury. However, the most complex fires had a lower injury incidence rate than less complex fires. Although fire complexity and the number of firefighters were associated with the risk for at least one reported injury, the more experienced and specialized firefighting teams had lower injury incidence. Copyright © 2013 Elsevier Inc. All rights reserved.

The national Fire and Fire Surrogate study: effects of fuel reduction methods on forest vegetation structure and fuels

Treesearch

Dylan W. Schwilk; Jon E. Keeley; Eric E. Knapp; James Mciver; John D. Bailey; Christopher J. Fettig; Carl E. Fiedler; Richy J. Harrod; Jason J. Moghaddas; Kenneth W. Outcalt; Carl N. Skinner; Scott L. Stephens; Thomas A. Waldrop; Daniel A. Yaussy; Andrew Youngblood

2009-01-01

Changes in vegetation and fuels were evaluated from measurements taken before and after fuel reduction treatments (prescribed fire, mechanical treatments, and the combination of the two) at 12 Fire and Fire Surrogate (FFS) sites located in forests with a surface fire regime across the conterminous United States. To test the relative effectiveness of fuel reduction...

Firewalls in bee nests-survival value of propolis walls of wild Cape honeybee (Apis mellifera capensis).

PubMed

Tribe, Geoff; Tautz, Jürgen; Sternberg, Karin; Cullinan, Jenny

2017-04-01

The Cape bee is endemic to the winter rainfall region of South Africa where fires are an integral part of the ecology of the fynbos (heathland) vegetation. Of the 37 wild nests in pristine Peninsula Sandstone Fynbos in the Cape Point section of Table Mountain National Park that have been analyzed so far, only 22 could be accessed sufficiently to determine the existence of a propolis wall of which 68% had propolis walls which entirely enclosed their openings. The analysis of the 37 wild nests revealed that 78% occurred under boulders or in clefts within rocks, 11% in the ground, 8% in tree cavities, and 3% within shrubs. The analysis of 17 of these nests following a fire within the park revealed that the propolis walls materially protected the nests and retarded the fire with all the colonies surviving. The bees responded to the smoke by imbibing honey and retreating to the furthest recess of their nest cavity. The bees were required to utilize this honey for about 3 weeks after which fire-loving plants appeared and began flowering. Considerable resources were utilized in the construction of the propolis walls, which ranged in thickness from 1.5 to 40 mm (mean 5 mm). Its physical environment determines the nesting behavior of the Cape bee. The prolific use of propolis serves to insulate the nest from extremes of temperature and humidity, restricts entry, camouflages the nest, and acts as an effective fire barrier protecting nests established mostly under rocks in vegetation subjected to periodic fires.

Firewalls in bee nests—survival value of propolis walls of wild Cape honeybee ( Apis mellifera capensis)

NASA Astrophysics Data System (ADS)

Tribe, Geoff; Tautz, Jürgen; Sternberg, Karin; Cullinan, Jenny

2017-04-01

The Cape bee is endemic to the winter rainfall region of South Africa where fires are an integral part of the ecology of the fynbos (heathland) vegetation. Of the 37 wild nests in pristine Peninsula Sandstone Fynbos in the Cape Point section of Table Mountain National Park that have been analyzed so far, only 22 could be accessed sufficiently to determine the existence of a propolis wall of which 68% had propolis walls which entirely enclosed their openings. The analysis of the 37 wild nests revealed that 78% occurred under boulders or in clefts within rocks, 11% in the ground, 8% in tree cavities, and 3% within shrubs. The analysis of 17 of these nests following a fire within the park revealed that the propolis walls materially protected the nests and retarded the fire with all the colonies surviving. The bees responded to the smoke by imbibing honey and retreating to the furthest recess of their nest cavity. The bees were required to utilize this honey for about 3 weeks after which fire-loving plants appeared and began flowering. Considerable resources were utilized in the construction of the propolis walls, which ranged in thickness from 1.5 to 40 mm (mean 5 mm). Its physical environment determines the nesting behavior of the Cape bee. The prolific use of propolis serves to insulate the nest from extremes of temperature and humidity, restricts entry, camouflages the nest, and acts as an effective fire barrier protecting nests established mostly under rocks in vegetation subjected to periodic fires.

Response Mechanism: Blast/Fire Interactions.

DTIC Science & Technology

1983-11-01

A WORK UNIT NUMBERS University of Notre Dame Notre Dame, IN L FEMA WU No. 2564H ItI. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE Fedqral...Fires 9 Class A Fires 10 Control by Physics or Chemistry? 11 Conments 14 EXTINCTION AND IGNITION 15 Pool Fire 15 Analysis 17 Charring Solid Fire 21...post-explosion time, although its magnitude may make the efforts to control appear futile in the wake of a nuclear attack. There is considerable

Fire containment tests of aircraft interior panels

NASA Technical Reports Server (NTRS)

Kourtides, D. A.; Parker, J. A.; Leon, H. A.; Williamson, R. B.; Hasegawa, H.; Fisher, F.; Draemel, R.; Marcussen, W. H.; Hilado, C. J.

1976-01-01

The paper describes an experimental program carried out to evaluate a possible method for testing the fire-containment qualities of aircraft interior panels. The experimental apparatus consisted of a burner that simulates various fire loads under different ventilation conditions in an enclosure of approximately the same size as an aircraft lavatory module. Two fire-containment tests are discussed in which two adjoining walls of the enclosure were made from state-of-the-art composite panels; rats were exposed to the combustion products in order to evaluate the toxic threat posed by those products. The results show that the burner can be employed to represent various fire-load conditions and that the methodology developed for fire containment can be useful in evaluating the fire resistance of composite panels before conducting large-scale tests. It is concluded that elements of the fire-containment criteria include the temperature rise on the backface of the panels as a function of time, the flame burn-through by either decomposition or severe distortion of the material, and the toxicity of the combustion gases evolved.

Influence of the contractile properties of muscle on motor unit firing rates during a moderate-intensity contraction in vivo.

PubMed

Trevino, Michael A; Herda, Trent J; Fry, Andrew C; Gallagher, Philip M; Vardiman, John P; Mosier, Eric M; Miller, Jonathan D

2016-08-01

It is suggested that firing rate characteristics of motor units (MUs) are influenced by the physical properties of the muscle. However, no study has correlated MU firing rates at recruitment, targeted force, or derecruitment with the contractile properties of the muscle in vivo. Twelve participants (age = 20.67 ± 2.35 yr) performed a 40% isometric maximal voluntary contraction of the leg extensors that included linearly increasing, steady force, and decreasing segments. Muscle biopsies were collected with myosin heavy chain (MHC) content quantified, and surface electromyography (EMG) was recorded from the vastus lateralis. The EMG signal was decomposed into the firing events of single MUs. Slopes and y-intercepts were calculated for 1) firing rates at recruitment vs. recruitment threshold, 2) mean firing rates at steady force vs. recruitment threshold, and 3) firing rates at derecruitment vs. derecruitment threshold relationships for each subject. Correlations among type I %MHC isoform content and the slopes and y-intercepts from the three relationships were examined. Type I %MHC isoform content was correlated with MU firing rates at recruitment (y-intercepts: r = -0.577; slopes: r = 0.741) and targeted force (slopes: r = 0.853) vs. recruitment threshold and MU firing rates at derecruitment (y-intercept: r = -0.597; slopes: r = 0.701) vs. derecruitment threshold relationships. However, the majority of the individual MU firing rates vs. recruitment and derecruitment relationships were not significant (P > 0.05) and, thus, revealed no systematic pattern. In contrast, MU firing rates during the steady force demonstrated a systematic pattern with higher firing rates for the lower- than higher-threshold MUs and were correlated with the physical properties of MUs in vivo. Copyright © 2016 the American Physiological Society.

Particulate matter and black carbon optical properties and emission factors from prescribed fires in the southeastern United States

EPA Science Inventory

The aerosol emissions from prescribed fires in the Southeastern United States were measured and compared to emissions from laboratory burns with fuels collected from the site. Fine particulate matter (PM2.5), black carbon, and aerosol light scattering and absorption were characte...

Restoring fire suppressed Texas pak woodlands to historic conditions using prescribed fire

Treesearch

Jeff C. Sparks; Michael C. Stambaugh; Eric L. Keith

2012-01-01

Comparable to many oak ecosystems across the eastern United States, oak woodlands in Texas display characteristics of changing composition and structure due to altered fire regimes. Information describing historic fire regimes suggests woodlands underwent relatively frequent and repeated burning prior to major Euro-American influence in the early 19th century. Oak...

46 CFR 108.477 - Fire hydrants.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fire hydrants. 108.477 Section 108.477 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Foam Extinguishing Systems § 108.477 Fire hydrants. (a) If a fixed foam...

75 FR 62307 - Fire Prevention Week, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-08

... Prevention Week, 2010 By the President of the United States of America A Proclamation During Fire Prevention Week, we reaffirm the importance of fire safety and awareness, and we pay tribute to our firefighters..., injuries, and lives lost to fire and its consequences. Fire Prevention Week also calls our attention to the...

Fire Safety. Managing School Facilities, Guide 6.

ERIC Educational Resources Information Center

Department for Education and Employment, London (England). Architects and Building Branch.

This booklet discusses how United Kingdom schools can manage fire safety and minimize the risk of fire. The guide examines what legislation school buildings must comply with and covers the major risks. It also describes training and evacuation procedures and provides guidance on fire precautions, alarm systems, fire fighting equipment, and escape…

Wildland fire deficit and surplus in the western United States, 1984-2012

Treesearch

Sean A. Parks; Carol Miller; Marc-Andre Parisien; Lisa M. Holsinger; Solomon Z. Dobrowski; John Abatzoglou

2015-01-01

Wildland fire is an important disturbance agent in the western US and globally. However, the natural role of fire has been disrupted in many regions due to the influence of human activities, which have the potential to either exclude or promote fire, resulting in a "fire deficit" or "fire surplus", respectively. In this study, we developed...

30 CFR 36.31 - Fire extinguisher.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fire extinguisher. 36.31 Section 36.31 Mineral... Construction and Design Requirements § 36.31 Fire extinguisher. Each unit of mobile diesel-powered transportation equipment shall be fitted with a fire extinguisher carried in a location easily accessible to the...

Fire-probability maps for the Brazilian Amazonia

NASA Astrophysics Data System (ADS)

Cardoso, M.; Nobre, C.; Obregon, G.; Sampaio, G.

2009-04-01

Most fires in Amazonia result from the combination between climate and land-use factors. They occur mainly in the dry season and are used as an inexpensive tool for land clearing and management. However, their unintended consequences are of important concern. Fire emissions are the most important sources of greenhouse gases and aerosols in the region, accidental fires are a major threat to protected areas, and frequent fires may lead to permanent conversion of forest areas into savannas. Fire-activity models have thus become important tools for environmental analyses in Amazonia. They are used, for example, in warning systems for monitoring the risk of burnings in protected areas, to improve the description of biogeochemical cycles and vegetation composition in ecosystem models, and to help estimate the long-term potential for savannas in biome models. Previous modeling studies for the whole region were produced in units of satellite fire pixels, which complicate their direct use for environmental applications. By reinterpreting remote-sensing based data using a statistical approach, we were able to calibrate models for the whole region in units of probability, or chance of fires to occur. The application of these models for years 2005 and 2006 provided maps of fire potential at 3-month and 0.25-deg resolution as a function of precipitation and distance from main roads. In both years, the performance of the resulting maps was better for the period July-September. During these months, most of satellite-based fire observations were located in areas with relatively high chance of fire, as determined by the modeled probability maps. In addition to reproduce reasonably well the areas presenting maximum fire activity as detected by remote sensing, the new results in units of probability are easier to apply than previous estimates from fire-pixel models.

Fire-probability maps for the Brazilian Amazonia

NASA Astrophysics Data System (ADS)

Cardoso, Manoel; Sampaio, Gilvan; Obregon, Guillermo; Nobre, Carlos

2010-05-01

Most fires in Amazonia result from the combination between climate and land-use factors. They occur mainly in the dry season and are used as an inexpensive tool for land clearing and management. However, their unintended consequences are of important concern. Fire emissions are the most important sources of greenhouse gases and aerosols in the region, accidental fires are a major threat to protected areas, and frequent fires may lead to permanent conversion of forest areas into savannas. Fire-activity models have thus become important tools for environmental analyses in Amazonia. They are used, for example, in warning systems for monitoring the risk of burnings in protected areas, to improve the description of biogeochemical cycles and vegetation composition in ecosystem models, and to help estimate the long-term potential for savannas in biome models. Previous modeling studies for the whole region were produced in units of satellite fire pixels, which complicate their direct use for environmental applications. By reinterpreting remote-sensing based data using a statistical approach, we were able to calibrate models for the whole region in units of probability, or chance of fires to occur. The application of these models for years 2005 and 2006 provided maps of fire potential at 3-month and 0.25-deg resolution as a function of precipitation and distance from main roads. In both years, the performance of the resulting maps was better for the period July-September. During these months, most of satellite-based fire observations were located in areas with relatively high chance of fire, as determined by the modeled probability maps. In addition to reproduce reasonably well the areas presenting maximum fire activity as detected by remote sensing, the new results in units of probability are easier to apply than previous estimates from fire-pixel models.

46 CFR 108.405 - Fire detection system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire detection system. 108.405 Section 108.405 Shipping... EQUIPMENT Fire Extinguishing Systems § 108.405 Fire detection system. (a) Each fire detection system and each smoke detection system on a unit must— (1) Be approved by the Commandant; and (2) Have a visual...

Effects of fire and fire surrogate treatments on bark beetle-caused tree mortality in the Southern Cascades, California

Treesearch

C.J. Fettig; R.R. Borys; C.P. and Dabney

2010-01-01

We examined bark beetle responses to fire and fire surrogate treatments 2 and 4 years after the application of prescribed fire in a mixed-conifer forest in northern California. Treatments included an untreated control (C), thinning from below (T), and applications of prescribed fire (B) and T + B replicated three times in 10-ha experimental units. A total of 1,822...

Charts for interpreting wildland fire behavior characteristics

Treesearch

Patricia L. Andrews; Richard C. Rothermel

1982-01-01

The fire characteristics chart is proposed as a graphical method ofpresenting two primary characteristics of fire behavior – spread rate and intensity. Its primary use is communicating and interpreting either site-specific predictions of fire behavior or National Fire-Danger Rating System (NFDRS) indexes and components. Rate of spread, heat per unit area, flame length...

Terahop and Lawrence Livermore National LaboratoryStructural Fire RF Testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haugen, P; Pratt, G

The Georgia Public Safety Training Center's Live Fire Training Facility in Forsyth, GA is a three story structure constructed of rebar-reinforced concrete wall and floors. All the door and window coverings on the building are constructed of thick, plate metal to withstand the high temperatures generated inside the building during training exercises. All of the building's walls and floors are 1-foot thick, and regular concrete columns run up along the inside of the wall increasing the thickness to 20-inches in those locations. A center concrete staircase divides the structure in half. For typical exercises, fires are started in the backmore » right corner of the building on the first floor and in the front right corner on the second floor as shown in Figure 2. Due to the high heat generated during these exercises, measured at 300 F on the floor and 700 F near the ceilings, there were limited locations at which equipment could be placed that did not incorporate heat shielding, such as the Lawrence Livermore National Laboratory's UWB system. However, upon inspection of the building, two preferable locations were identified in which equipment could be placed that would be protected from the temperature extremes generated by the fires. These locations are identified in Figure 2 as the tested TX locations. These were preferred locations because, while they protected the hardware from temperature extremes, they also force the RF transmission path through the building to cross very near the fire locations and anticipated plasma generation regions. Both of the locations listed in Figure 2 were tested by the UWB equipment and found to be suitable deployment locations to establish a solid RF link for data collection. The transmission location on the first floor was ultimately chosen for use during the actual exercises because it was accessible to the data collection team during the exercises. This allowed them to remove the hardware once the testing was complete without

Impacts of changing fire weather conditions on reconstructed trends in U.S. wildland fire activity from 1979 to 2014

Treesearch

Patrick H. Freeborn; W. Matt Jolly; Mark A. Cochrane

2016-01-01

One component of climate‐fire interactions is the relationship between weather conditions concurrent with burning (i.e., fire danger) and the magnitude of fire activity. Here daily environmental conditions are associated with daily observations of fire activity within ecoregions across the continental United States (CONUS) by aligning the latter 12 years of a 36 year...

Slow carbon and nutrient accumulation in trees established following fire exclusion in the southwestern United States.

PubMed

Kaye, Jason P; Kaye, Margot W; Hart, Stephen C; Covington, W Wallace; Fulé, Peter Z

2016-12-01

Increasing tree density that followed fire exclusion after the 1880s in the southwestern United States may have also altered nutrient cycles and led to a carbon (C) sink that constitutes a significant component of the U.S. C budget. Yet, empirical data quantifying century-scale changes in C or nutrients due to fire exclusion are rare. We used tree-ring reconstructions of stand structure from five ponderosa pine-dominated sites from across northern Arizona to compare live tree C, nitrogen (N), and phosphorus (P) storage between the 1880s and 1990s. Live tree biomass in the 1990s contained up to three times more C, N, and P than in 1880s. However, the increase in C storage was smaller than values used in recent U.S. C budgets. Furthermore, trees that had established prior to the 1880s accounted for a large fraction (28-66%) of the C, N, and P stored in contemporary stands. Overall, our century-scale analysis revealed that forests of the 1880s were on a trajectory to accumulate C and nutrients in trees even in the absence of fire exclusion, either because growing conditions became more favorable after the 1880s or because forests in the 1880s included age or size cohorts poised for accelerated growth. These results may lead to a reduction in the C sink attributed to fire exclusion, and they refine our understanding of reference conditions for restoration management of fire-prone forests. © 2016 by the Ecological Society of America.

EcoSmart Fire as structure ignition model in wildland urban interface: predictions and validations

Treesearch

Mark A. Dietenberger; Charles R. Boardman

2016-01-01

EcoSmartFire is a Windows program that models heat damage and piloted ignition of structures from radiant exposure to discrete landscaped tree fires. It calculates the radiant heat transfer from cylindrical shaped fires to the walls and roof of the structure while accounting for radiation shadowing, attenuation, and ground reflections. Tests of litter burn, a 0.6 m...

Old Fire/Grand Prix Fire, California

NASA Image and Video Library

2003-11-19

On November 18, 2003, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite acquired this image of the Old Fire/Grand Prix fire east of Los Angeles. The image is being processed by NASA's Wildfire Response Team and will be sent to the United States Department of Agriculture's Forest Service Remote Sensing Applications Center (RSAC) which provides interpretation services to Burned Area Emergency Response (BAER) teams to assist in mapping the severity of the burned areas. The image combines data from the visible and infrared wavelength regions to highlight the burned areas. http://photojournal.jpl.nasa.gov/catalog/PIA04879

Fire protection review revisit no. 2, Argonne National Laboratory, Argonne, Illinois

NASA Astrophysics Data System (ADS)

Dobson, P. H.; Earley, M. W.; Mattern, L. J.

1985-05-01

A fire protection survey was conducted at Argonne National Laboratory on April 1-5, 8-12, and April 29-May 2, 1985. The purpose was to review the facility fire protection program and to make recommendations or identify areas according to criteria established by the Department of Energy. There has been a substantial improvement in fire protection at this laboratory since the 1977 audit. Numerous areas which were previously provided with detection systems only have since been provided with automatic sprinkler protection. The following basic fire protection features are not properly controlled: (1) resealing wall and floor penetrations between fire areas after installation of services; (2) cutting and welding; and (3) housekeeping. The present Fire Department manpower level appears adequate to control a route fire. Their ability to adequately handle a high-challenge fire, or one involving injuries to personnel, or fire spread beyond the initial fire area is doubtful.

Advancing dendrochronological studies of fire in the United States

Treesearch

Grant L. Harley; Christopher H. Baisan; Peter M. Brown; Donald A. Falk; William T. Flatley; Henri D. Grissino-Mayer; Amy Hessl; Emily K. Heyerdahl; Margot W. Kaye; Charles W. Lafon; Ellis Q. Margolis; R. Stockton Maxwell; Adam T. Naito; William J. Platt; Monica T. Rother; Thomas Saladyga; Rosemary L. Sherriff; Lauren A. Stachowiak; Michael C. Stambaugh; Elaine Kennedy Sutherland; Alan H. Taylor

2018-01-01

Dendroecology is the science that dates tree rings to their exact calendar year of formation to study processes that influence forest ecology (e.g., Speer 2010 [1], Amoroso et al., 2017 [2]). Reconstruction of past fire regimes is a core application of dendroecology, linking fire history to population dynamics and climate effects on tree growth and survivorship. Since...

Assessing risks to spotted owls from forest thinning in fire-adapted forests of the western United States

Treesearch

Danny C. Lee; Larry L. Irwin

2005-01-01

Concern for viable spotted owl (Strix occidentalis) populations has played prominently in the management of western forests in the United States. Historically, much of the debate has focused on the impacts of commercial timber harvest. Increasingly, the conflict is shifting to the habitat needs of owls versus the need for active management of fire-...

Fire intensity impacts on post-fire temperate coniferous forest net primary productivity

NASA Astrophysics Data System (ADS)

Sparks, Aaron M.; Kolden, Crystal A.; Smith, Alistair M. S.; Boschetti, Luigi; Johnson, Daniel M.; Cochrane, Mark A.

2018-02-01

Fire is a dynamic ecological process in forests and impacts the carbon (C) cycle through direct combustion emissions, tree mortality, and by impairing the ability of surviving trees to sequester carbon. While studies on young trees have demonstrated that fire intensity is a determinant of post-fire net primary productivity, wildland fires on landscape to regional scales have largely been assumed to either cause tree mortality, or conversely, cause no physiological impact, ignoring the impacted but surviving trees. Our objective was to understand how fire intensity affects post-fire net primary productivity in conifer-dominated forested ecosystems on the spatial scale of large wildland fires. We examined the relationships between fire radiative power (FRP), its temporal integral (fire radiative energy - FRE), and net primary productivity (NPP) using 16 years of data from the MOderate Resolution Imaging Spectrometer (MODIS) for 15 large fires in western United States coniferous forests. The greatest NPP post-fire loss occurred 1 year post-fire and ranged from -67 to -312 g C m-2 yr-1 (-13 to -54 %) across all fires. Forests dominated by fire-resistant species (species that typically survive low-intensity fires) experienced the lowest relative NPP reductions compared to forests with less resistant species. Post-fire NPP in forests that were dominated by fire-susceptible species were not as sensitive to FRP or FRE, indicating that NPP in these forests may be reduced to similar levels regardless of fire intensity. Conversely, post-fire NPP in forests dominated by fire-resistant and mixed species decreased with increasing FRP or FRE. In some cases, this dose-response relationship persisted for more than a decade post-fire, highlighting a legacy effect of fire intensity on post-fire C dynamics in these forests.

Concepts for Future Large Fire Modeling

Treesearch

A. P. Dimitrakopoulos; R. E. Martin

1987-01-01

A small number of fires escape initial attack suppression efforts and become large, but their effects are significant and disproportionate. In 1983, of 200,000 wildland fires in the United States, only 4,000 exceeded 100 acres. However, these escaped fires accounted for roughly 95 percent of wildfire-related costs and damages (Pyne, 1984). Thus, future research efforts...

Varied ecosystems need different fire protection

USGS Publications Warehouse

Gutsell, Sheri L.; Johnson, Edward A.; Miyanishi, Kiyoko; Keeley, Jon E.; Dickinson, Matthew; Bridge, Simon R. J.

2001-01-01

Covington states in his Commentary1 that the open ponderosa pine forests of the western United States are "in widespread collapse" because fire suppression by humans has eliminated the low-intensity surface fire regime that maintained the open, park-like structure of these forests. He fears this will lead to an "unprecedented" crown fire regime that will eliminate forests.

EVALUATION OF UTILITY BOILER RADIANT FURNACE RESIDENCE TIME/TEMPERATURE CHARACTERISTICS: FIELD TESTS AND HEAT TRANSFER MODELING

EPA Science Inventory

The report describes an investigation of the adequacy of a modeling approach in predicting the thermal environment and flow field of pulverized-coal-fired utility boilers. Two 420 MWe coal-fired boilers were evaluated: a single-wall-fired unit and a tangentially fired unit, repre...

U.S. conterminous wall-to-wall anthropogenic land use trends (NWALT), 1974–2012

USGS Publications Warehouse

Falcone, James A.

2015-09-14

This dataset provides a U.S. national 60-meter, 19-class mapping of anthropogenic land uses for five time periods: 1974, 1982, 1992, 2002, and 2012. The 2012 dataset is based on a slightly modified version of the National Land Cover Database 2011 (NLCD 2011) that was recoded to a schema of land uses, and mapped back in time to develop datasets for the four earlier eras. The time periods coincide with U.S. Department of Agriculture (USDA) Census of Agriculture data collection years. Changes are derived from (a) known changes in water bodies from reservoir construction or removal; (b) housing unit density changes; (c) regional mining/extraction trends; (d) for 1999–2012, timber and forestry activity based on U.S. Geological Survey (USGS) Landscape Fire and Resource Management Planning Tools (Landfire) data; (e) county-level USDA Census of Agriculture change in cultivated land; and (f) establishment dates of major conservation areas. The data are compared to several other published studies and datasets as validation. Caveats are provided about limitations of the data for some classes. The work was completed as part of the USGS National Water-Quality Assessment (NAWQA) Program and termed the NAWQA Wall-to-Wall Anthropogenic Land Use Trends (NWALT) dataset. The associated datasets include five 60-meter geospatial rasters showing anthropogenic land use for the years 1974, 1982, 1992, 2002, and 2012, and 14 rasters showing the annual extent of timber clearcutting and harvest from 1999 to 2012.

A comparison of geospatially modeled fire behavior and fire management utility of three data sources in the southeastern United States

Treesearch

LaWen T. Hollingsworth; Laurie L. Kurth; Bernard R. Parresol; Roger D. Ottmar; Susan J. Prichard

2012-01-01

Landscape-scale fire behavior analyses are important to inform decisions on resource management projects that meet land management objectives and protect values from adverse consequences of fire. Deterministic and probabilistic geospatial fire behavior analyses are conducted with various modeling systems including FARSITE, FlamMap, FSPro, and Large Fire Simulation...

Acute effects of dynamic exercises on the relationship between the motor unit firing rate and the recruitment threshold.

PubMed

Ye, Xin; Beck, Travis W; DeFreitas, Jason M; Wages, Nathan P

2015-04-01

The aim of this study was to compare the acute effects of concentric versus eccentric exercise on motor control strategies. Fifteen men performed six sets of 10 repetitions of maximal concentric exercises or eccentric isokinetic exercises with their dominant elbow flexors on separate experimental visits. Before and after the exercise, maximal strength testing and submaximal trapezoid isometric contractions (40% of the maximal force) were performed. Both exercise conditions caused significant strength loss in the elbow flexors, but the loss was greater following the eccentric exercise (t=2.401, P=.031). The surface electromyographic signals obtained from the submaximal trapezoid isometric contractions were decomposed into individual motor unit action potential trains. For each submaximal trapezoid isometric contraction, the relationship between the average motor unit firing rate and the recruitment threshold was examined using linear regression analysis. In contrast to the concentric exercise, which did not cause significant changes in the mean linear slope coefficient and y-intercept of the linear regression line, the eccentric exercise resulted in a lower mean linear slope and an increased mean y-intercept, thereby indicating that increasing the firing rates of low-threshold motor units may be more important than recruiting high-threshold motor units to compensate for eccentric exercise-induced strength loss. Copyright © 2014 Elsevier B.V. All rights reserved.

Dow’s fire and explosion index: a case-study in the process unit of an oil extraction factory

PubMed Central

Nezamodini, Zeynab Sadat; Rezvani, Zahra; Kian, Kumars

2017-01-01

Introduction The incidence of fires and explosions have led to severe damage in many industries, primarily in industries’ financial losses. This study was conducted to estimate losses due to fire and explosion and the impact of control measures on the number of losses applying Dow’s Fire and Explosion Index. Methods This is a case study conducted in one of the process units of an oil extraction factory. Dow’s Fire and Explosion Index Hazard classification guide, 7th edition, issued by the American Institute of Chemical Engineers was applied. Data were obtained mainly through interviews and consultation with experts, as well as reported operating parameters and process documents. Results The Dow Index of the processing unit was estimated to be 243.68, and the most probable base damage was approximately $4.15 million in 2008. The actual damages were estimated to be $2,863,500, and the number of lost work days to be 64.56 days. The interruption losses were estimated to be $15,817,200 and the total losses to the system to be $18.67 million. These results demonstrated that losses resulting from production interruptions are greater than losses due to the destruction of equipment. A series of corrections was then proposed and risk analysis was performed again to examine the effects of reforms. The comparison shows that by applying reforms the FEI can change to 86.62 and the total loss can reduce to $9.03 million. Conclusion This study shows that Dow’s Index is a systematic tool to examine the impact of control measures. It also enhances resource management considering an optimal insurance contract. Considering the priority of reducing damage factors, several correction actions were suggested, such as modifying the drainage system, installation of hexane detectors, an automatic sprinkler system, fire detectors on the cable tray, and finally, using the water spray washing on the tanks. PMID:28465821

Off-wall boundary conditions for turbulent flows obtained from buffer-layer minimal flow units

NASA Astrophysics Data System (ADS)

Garcia-Mayoral, Ricardo; Pierce, Brian; Wallace, James

2012-11-01

There is strong evidence that the transport processes in the buffer region of wall-bounded turbulence are common across various flow configurations, even in the embryonic turbulence in transition (Park et al., Phys. Fl. 24). We use this premise to develop off-wall boundary conditions for turbulent simulations. Boundary conditions are constructed from DNS databases using periodic minimal flow units and reduced order modeling. The DNS data was taken from a channel at Reτ = 400 and a zero-pressure gradient transitional boundary layer (Sayadi et al., submitted to J . FluidMech .) . Both types of boundary conditions were first tested on a DNS of the core of the channel flow with the aim of extending their application to LES and to spatially evolving flows. 2012 CTR Summer Program.

Tested by fire: the cone fire and the lessons of an accidental experiment

Treesearch

Sussanne Maleki; Carl Featured: Skinner; Martin Ritchie

2007-01-01

Catastrophic wildfires burn every year in the forests of the Western United States. In the past, low-intensity wildfires were common and played an important ecological role that benefited these forests. But fire suppression policies over the last century have interrupted natural fire regimes. As a result, forests that were once characterized by an open structure and...

30 CFR 77.1909-1 - Use of nonpermissible explosives and nonpermissible shot-firing units; approval by Health and...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Use of nonpermissible explosives and nonpermissible shot-firing units; approval by Health and Safety District Manager. 77.1909-1 Section 77.1909-1...; approval by Health and Safety District Manager. Where the Coal Mine Health and Safety District Manager has...

A Drought Index for Forest Fire Control

Treesearch

John J. Keetch; George M. Byram

1968-01-01

The moisture content of the upper soil, as well as that of the covering layer of duff, has an important effect on the fire suppression effort in forest and wildland areas. In certain forested areas of the United States, fires in deep duff fuels are of particular concern to the fire control manager. When these fuels are dry, fires burn deeply, dam-age is excessive, and...

Wallace L. Fons: fire research pioneer

Treesearch

David R. Weise; Ted R. Fons

2014-01-01

During his 30-year career with the U.S. Forest Service, Wally Fons laid the foundation for much of the understanding we have today of forest fire's many properties by applying his mechanical engineering background. He left a legacy of research that formed the basis for the fire behavior and danger systems still used in the United States. In addition to fire...

76 FR 63801 - Fire Prevention Week, 2011

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-13

... Vol. 76 Thursday, No. 198 October 13, 2011 Part IV The President Proclamation 8732--Fire... 8732 of October 7, 2011 Fire Prevention Week, 2011 By the President of the United States of America A Proclamation Fires, whether caused by people or nature, can have devastating effects. Hundreds of thousands of...

Ecological consequences of alternative fuel reduction treatments in seasonally dry forests: the national fire and fire surrogate study

Treesearch

J.D. McIver; C.J. Fettig

2010-01-01

This special issue of Forest Science features the national Fire and Fire Surrogate study (FFS), a niultisite, multivariate research project that evaluates the ecological consequences of prescribed fire and its mechanical surrogates in seasonally dry forests of the United States. The need for a comprehensive national FFS study stemmed from concern that information on...

Assessment of wildland fire impacts on watershed annual water yield: Analytical framework and case studies in the United States

DOE PAGES

Hallema, Dennis W.; Sun, Ge; Caldwell, Peter V.; ...

2016-11-29

More than 50% of water supplies in the conterminous United States originate on forestland or rangeland and are potentially under increasing stress as a result of larger and more severe wildfires. Little is known, however, about the long-term impacts of fire on annual water yield and the role of climate variability within this context. We here propose a framework for evaluating wildland fire impacts on streamflow that combines double-mass analysis with new methods (change point analysis, climate elasticity modeling, and process-based modeling) to distinguish between multiyear fire and climate impacts. The framework captures a wide range of fire types, watershedsmore » characteristics, and climate conditions using streamflow data, as opposed to other approaches requiring paired watersheds. The process is illustrated with three case studies. A watershed in Arizona experienced a +266% increase in annual water yield in the 5 years after a wildfire, where +219% was attributed to wildfire and +24% to precipitation trends. In contrast, a California watershed had a lower (–64%) post-fire net water yield, comprised of enhanced flow (+38%) attributed to wildfire offset (–102%) by lower precipitation in the post-fire period. Changes in streamflow within a watershed in South Carolina had no apparent link to periods of prescribed burning but matched a very wet winter and reports of storm damage. As a result, the presented framework is unique in its ability to detect and quantify fire or other disturbances, even if the date or nature of the disturbance event is uncertain, and regardless of precipitation trends.« less

Assessment of wildland fire impacts on watershed annual water yield: Analytical framework and case studies in the United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hallema, Dennis W.; Sun, Ge; Caldwell, Peter V.

More than 50% of water supplies in the conterminous United States originate on forestland or rangeland and are potentially under increasing stress as a result of larger and more severe wildfires. Little is known, however, about the long-term impacts of fire on annual water yield and the role of climate variability within this context. We here propose a framework for evaluating wildland fire impacts on streamflow that combines double-mass analysis with new methods (change point analysis, climate elasticity modeling, and process-based modeling) to distinguish between multiyear fire and climate impacts. The framework captures a wide range of fire types, watershedsmore » characteristics, and climate conditions using streamflow data, as opposed to other approaches requiring paired watersheds. The process is illustrated with three case studies. A watershed in Arizona experienced a +266% increase in annual water yield in the 5 years after a wildfire, where +219% was attributed to wildfire and +24% to precipitation trends. In contrast, a California watershed had a lower (–64%) post-fire net water yield, comprised of enhanced flow (+38%) attributed to wildfire offset (–102%) by lower precipitation in the post-fire period. Changes in streamflow within a watershed in South Carolina had no apparent link to periods of prescribed burning but matched a very wet winter and reports of storm damage. As a result, the presented framework is unique in its ability to detect and quantify fire or other disturbances, even if the date or nature of the disturbance event is uncertain, and regardless of precipitation trends.« less

Wildland fire emissions, carbon, and climate: wildland fire detection and burned area in the United States

Treesearch

Wei Min Hao; Narasimhan K. Larkin

2014-01-01

Biomass burning is a major source of greenhouse gases, aerosols, black carbon, and atmospheric pollutants that affects regional and global climate and air quality. The spatial and temporal extent of fires and the size of burned areas are critical parameters in the estimation of fire emissions. Tremendous efforts have been made in the past 12 years to characterize the...

76 FR 3587 - Standards of Performance for Fossil-Fuel-Fired, Electric Utility, Industrial-Commercial...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

... Standards of Performance for Fossil-Fuel-Fired, Electric Utility, Industrial-Commercial-Institutional, and... Fossil fuel-fired electric utility steam generating units. Federal Government 22112 Fossil fuel-fired... 22112 Fossil fuel-fired electric utility steam generating units owned by municipalities. 921150 Fossil...

Forest Fire Occurrence in Southern Counties, 1966-1975

Treesearch

M.L. Doolittle

1977-01-01

Forest fire occurrence data for individual protection units generally are unavailable outside particular state organization. Number of fires, area protected and fire occurrence rate (fires per 1,000,000 acres) from 1966 to 1975, are presented in tables for the 993 counties under protection in 13 southern states. These data are compared with data for the preceeding...

46 CFR 108.415 - Fire pump: General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... have at least two independently driven fire pumps that can each deliver water at a continuous pitot tube pressure of at least 3.5 kilograms per square centimeter (approximately 50 pounds per square inch) at least two fire hose nozzles that are connected to the highest two fire hydrants on the unit...

46 CFR 108.415 - Fire pump: General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... have at least two independently driven fire pumps that can each deliver water at a continuous pitot tube pressure of at least 3.5 kilograms per square centimeter (approximately 50 pounds per square inch) at least two fire hose nozzles that are connected to the highest two fire hydrants on the unit...

46 CFR 108.415 - Fire pump: General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... have at least two independently driven fire pumps that can each deliver water at a continuous pitot tube pressure of at least 3.5 kilograms per square centimeter (approximately 50 pounds per square inch) at least two fire hose nozzles that are connected to the highest two fire hydrants on the unit...

46 CFR 108.415 - Fire pump: General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... have at least two independently driven fire pumps that can each deliver water at a continuous pitot tube pressure of at least 3.5 kilograms per square centimeter (approximately 50 pounds per square inch) at least two fire hose nozzles that are connected to the highest two fire hydrants on the unit...

46 CFR 108.415 - Fire pump: General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... have at least two independently driven fire pumps that can each deliver water at a continuous pitot tube pressure of at least 3.5 kilograms per square centimeter (approximately 50 pounds per square inch) at least two fire hose nozzles that are connected to the highest two fire hydrants on the unit...

Predicting wildfire ignitions, escapes, and large fire activity using Predictive Service’s 7-Day Fire Potential Outlook in the western USA

Treesearch

Karin L. Riley; Crystal Stonesifer; Haiganoush Preisler; Dave Calkin

2014-01-01

Can fire potential forecasts assist with pre-positioning of fire suppression resources, which could result in a cost savings to the United States government? Here, we present a preliminary assessment of the 7-Day Fire Potential Outlook forecasts made by the Predictive Services program. We utilized historical fire occurrence data and archived forecasts to assess how...

Economic cost of initial attack and large-fire suppression

Treesearch

Armando González-Cabán

1983-01-01

A procedure has been developed for estimating the economic cost of initial attack and large-fire suppression. The procedure uses a per-unit approach to estimate total attack and suppression costs on an input-by-input basis. Fire management inputs (FMIs) are the production units used. All direct and indirect costs are charged to the FMIs. With the unit approach, all...

Fire and fire surrogate study in the Sierra Nevada: evaluating restoration treatments at Blodgett Forest and Sequoia National Park

Treesearch

Eric E. Knapp; Scott L. Stephens; James D. McIver; Jason J. Moghaddas; Jon E. Keeley

2004-01-01

Management practices have altered both the structure and function of forests throughout the United States. Some of the most dramatic changes have resulted from fire exclusion, especially in forests that historically experienced relatively frequent, low- to moderate-intensity fire regimes. In the Sierra Nevada, fire exclusion is believed to have resulted in widespread...

46 CFR 108.413 - Fusible element fire detection system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fusible element fire detection system. 108.413 Section... UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.413 Fusible element fire detection system. (a) A fusible element fire detection system may be installed. (b) The arrangements for the system...

Estimating the impact of the 2004 Alaskan forest fires on episodic particulate matter pollution over the eastern United States through assimilation of satellite-derived aerosol optical depths in a regional air quality model

NASA Astrophysics Data System (ADS)

Mathur, Rohit

2008-09-01

During the summer of 2004, extensive wildfires burned in Alaska and western Canada; the fires were the largest on record for Alaska. Smoke from these fires was observed over the continental United States in satellite images, and a variety of chemical tracers associated with the fires were sampled by aircrafts deployed during the International Consortium for Atmospheric Research on Transport and Transformation field experiment. Several recent studies have quantified the impacts of the long-range transport of pollution associated with these fires on tropospheric CO and O3 levels over the eastern United States. This study quantifies the episodic impact of this pollution transport event on surface-level fine particulate matter (PM2.5) concentrations over the eastern United States during mid-July 2004, through the complementary use of remotely sensed, aloft, and surface measurements, in conjunction with a comprehensive regional atmospheric chemistry-transport model. A methodology is developed to assimilate MODIS aerosol optical depths in the model to represent the impacts of the fires. The resultant model predictions of CO and PM2.5 distributions are compared extensively with corresponding surface and aloft measurements. On the basis of the model calculations, a 0.12Tg enhancement in tropospheric PM2.5 mass loading over the eastern United States is estimated on 19 July 2004 due to the fires. This amount is significantly larger (approximately a factor of 8) than the total daily anthropogenic fine particulate matter emissions for the continental United States. Analysis of measured and modeled PM2.5 surface-level concentrations suggests that the transport of particulate matter pollution associated with the fires resulted in a 24-42 % enhancement in median surface-level PM2.5 concentrations across the eastern United States during 19-23 July 2004.

Crew size affects fire fighting efficiency: A progress report on time studies of the fire fighting job.

Treesearch

Donald N. Matthews

1940-01-01

Fire fighting is still largely a hand-work job in the heavy cover and fuel conditions and rugged topography of the Douglas fir region, in spite of recent advances that have been made in %he use of machinery. Controlling a fire in this region requires immense amounts of work per unit of fire perimeter, so that large numbers of men are required to attack all but the...

Living with fire: Fire ecology and policy for the twenty-first century [book review

Treesearch

Carol Miller

2010-01-01

This is a well-written polemic about the failure of fire policy and management in the United States. The book contains enough ecology and history for nonspecialists to understand the complexities of the policy and management dilemmas that we face today. The authors provide a particularly good treatment of the diversity of roles that fire plays in different ecosystems,...

Impacts of fire and fire surrogate treatments on ecosystem nitrogen storage patterns: similarities and differences between forests of eastern and western North America

Treesearch

R.E.J. Boerner; J. Huang; S.C. Hart

2009-01-01

The Fire and Fire Surrogates (FFS) network is composed of 12 forest sites that span the continental UnitedStates, all of which historically had frequent low-severity fire. The goal of the FFS study was to assess the efficacy ofthree management treatments (prescribed fire, mechanical thinning, and their combination...

Unsupported inferences of high-severity fire in historical dry forests of the western United States: Response to Williams and Baker

USGS Publications Warehouse

Fulé, Peter Z.; Swetnam, Thomas W.; Brown, Peter M.; Falk, Donald A.; Peterson, David L.; Allen, Craig D.; Aplet, Gregory H.; Battaglia, Mike A.; Binkley, Dan; Farris, Calvin; Keane, Robert E.; Margolis, Ellis Q.; Grissino-Mayer, Henri; Miller, Carol; Sieg, Carolyn Hull; Skinner, Carl; Stephens, Scott L.; Taylor, Alan

2014-01-01

Reconstructions of dry western US forests in the late 19th century in Arizona, Colorado and Oregon based on General Land Office records were used by Williams & Baker (2012; Global Ecology and Biogeography, 21, 1042–1052; hereafter W&B) to infer past fire regimes with substantial moderate and high-severity burning. The authors concluded that present-day large, high-severity fires are not distinguishable from historical patterns. We present evidence of important errors in their study. First, the use of tree size distributions to reconstruct past fire severity and extent is not supported by empirical age–size relationships nor by studies that directly quantified disturbance history in these forests. Second, the fire severity classification of W&B is qualitatively different from most modern classification schemes, and is based on different types of data, leading to an inappropriate comparison. Third, we note that while W&B asserted ‘surprising’ heterogeneity in their reconstructions of stand density and species composition, their data are not substantially different from many previous studies which reached very different conclusions about subsequent forest and fire behaviour changes. Contrary to the conclusions of W&B, the preponderance of scientific evidence indicates that conservation of dry forest ecosystems in the western United States and their ecological, social and economic value is not consistent with a present-day disturbance regime of large, high-severity fires, especially under changing climate

A portable station for recording fire weather data

Treesearch

John R. Murray; Clive M. Countryman

1968-01-01

A portable station for recording fire weather data has been developed for use in wildland fires, prescribed burns, evaluating sites for fire weather stations, and fire research. Housed in a mechanic's tool box, the station weighs about 60 pounds. One man can have it ready to operate in about 15 minutes. The unit can record five weather variables, but additional...

46 CFR 161.002-2 - Types of fire-protective systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., but not be limited to, automatic fire and smoke detecting systems, manual fire alarm systems, sample... unit, fire detectors, smoke detectors, and audible and visual alarms distinct in both respects from the alarms of any other system not indicating fire. (c) Manual fire alarm systems. For the purpose of this...

46 CFR 108.403 - Fire extinguishing systems: General.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire extinguishing systems: General. 108.403 Section 108.403 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.403 Fire extinguishing systems: General. (a) Each...

46 CFR 108.403 - Fire extinguishing systems: General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Fire extinguishing systems: General. 108.403 Section 108.403 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.403 Fire extinguishing systems: General. (a) Each...

46 CFR 108.403 - Fire extinguishing systems: General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Fire extinguishing systems: General. 108.403 Section 108.403 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.403 Fire extinguishing systems: General. (a) Each...

46 CFR 108.403 - Fire extinguishing systems: General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fire extinguishing systems: General. 108.403 Section 108.403 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.403 Fire extinguishing systems: General. (a) Each...

46 CFR 108.403 - Fire extinguishing systems: General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Fire extinguishing systems: General. 108.403 Section 108.403 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.403 Fire extinguishing systems: General. (a) Each...

Recent Arctic tundra fire initiates widespread thermokarst development.

PubMed

Jones, Benjamin M; Grosse, Guido; Arp, Christopher D; Miller, Eric; Liu, Lin; Hayes, Daniel J; Larsen, Christopher F

2015-10-29

Fire-induced permafrost degradation is well documented in boreal forests, but the role of fires in initiating thermokarst development in Arctic tundra is less well understood. Here we show that Arctic tundra fires may induce widespread thaw subsidence of permafrost terrain in the first seven years following the disturbance. Quantitative analysis of airborne LiDAR data acquired two and seven years post-fire, detected permafrost thaw subsidence across 34% of the burned tundra area studied, compared to less than 1% in similar undisturbed, ice-rich tundra terrain units. The variability in thermokarst development appears to be influenced by the interaction of tundra fire burn severity and near-surface, ground-ice content. Subsidence was greatest in severely burned, ice-rich upland terrain (yedoma), accounting for ~50% of the detected subsidence, despite representing only 30% of the fire disturbed study area. Microtopography increased by 340% in this terrain unit as a result of ice wedge degradation. Increases in the frequency, magnitude, and severity of tundra fires will contribute to future thermokarst development and associated landscape change in Arctic tundra regions.

Recent Arctic tundra fire initiates widespread thermokarst development

PubMed Central

Jones, Benjamin M.; Grosse, Guido; Arp, Christopher D.; Miller, Eric; Liu, Lin; Hayes, Daniel J.; Larsen, Christopher F.

2015-01-01

Fire-induced permafrost degradation is well documented in boreal forests, but the role of fires in initiating thermokarst development in Arctic tundra is less well understood. Here we show that Arctic tundra fires may induce widespread thaw subsidence of permafrost terrain in the first seven years following the disturbance. Quantitative analysis of airborne LiDAR data acquired two and seven years post-fire, detected permafrost thaw subsidence across 34% of the burned tundra area studied, compared to less than 1% in similar undisturbed, ice-rich tundra terrain units. The variability in thermokarst development appears to be influenced by the interaction of tundra fire burn severity and near-surface, ground-ice content. Subsidence was greatest in severely burned, ice-rich upland terrain (yedoma), accounting for ~50% of the detected subsidence, despite representing only 30% of the fire disturbed study area. Microtopography increased by 340% in this terrain unit as a result of ice wedge degradation. Increases in the frequency, magnitude, and severity of tundra fires will contribute to future thermokarst development and associated landscape change in Arctic tundra regions. PMID:26511650

Recent Arctic tundra fire initiates widespread thermokarst development

DOE PAGES

Jones, Benjamin M.; Grosse, Guido; Arp, Christopher D.; ...

2015-10-29

Fire-induced permafrost degradation is well documented in boreal forests, but the role of fires in initiating thermokarst development in Arctic tundra is less well understood. Here we show that Arctic tundra fires may induce widespread thaw subsidence of permafrost terrain in the first seven years following the disturbance. Quantitative analysis of airborne LiDAR data acquired two and seven years post-fire, detected permafrost thaw subsidence across 34% of the burned tundra area studied, compared to less than 1% in similar undisturbed, ice-rich tundra terrain units. The variability in thermokarst development appears to be influenced by the interaction of tundra fire burnmore » severity and near-surface, ground-ice content. Subsidence was greatest in severely burned, ice-rich upland terrain (yedoma), accounting for -50% of the detected subsidence, despite representing only 30% of the fire disturbed study area. Microtopography increased by 340% in this terrain unit as a result of ice wedge degradation. Increases in the frequency, magnitude, and severity of tundra fires will contribute to future thermokarst development and associated landscape change in Arctic tundra regions.« less

Recent Arctic tundra fire initiates widespread thermokarst development

USGS Publications Warehouse

Jones, Benjamin M.; Grosse, Guido; Arp, Christopher D.; Miller, Eric K.; Liu, Lingli; Hayes, Daniel J.; Larsen, Christopher F.

2015-01-01

Fire-induced permafrost degradation is well documented in boreal forests, but the role of fires in initiating thermokarst development in Arctic tundra is less well understood. Here we show that Arctic tundra fires may induce widespread thaw subsidence of permafrost terrain in the first seven years following the disturbance. Quantitative analysis of airborne LiDAR data acquired two and seven years post-fire, detected permafrost thaw subsidence across 34% of the burned tundra area studied, compared to less than 1% in similar undisturbed, ice-rich tundra terrain units. The variability in thermokarst development appears to be influenced by the interaction of tundra fire burn severity and near-surface, ground-ice content. Subsidence was greatest in severely burned, ice-rich upland terrain (yedoma), accounting for ~50% of the detected subsidence, despite representing only 30% of the fire disturbed study area. Microtopography increased by 340% in this terrain unit as a result of ice wedge degradation. Increases in the frequency, magnitude, and severity of tundra fires will contribute to future thermokarst development and associated landscape change in Arctic tundra regions.

Development and demonstration of smoke plume, fire emissions, and pre- and postprescribed fire fuel models on North Carolina Coastal Plain forest ecosystems

Treesearch

Robert A. Mickler; Miriam Rorig; Christopher D. Geron; Gary L. Achtemier; Andrew D. Bailey; Candice Krull; David Brownlie

2007-01-01

Wildland fuels have been accumulating in the United States during at least the past half-century due to wildland fire management practices and policies. The additional fuels contribute to intense fire behavior, increase the costs of wildland fire control, and contribute to the degradation of local and regional air quality. The management of prescribed and wildland fire...

Quantifying post-fire fallen trees using multi-temporal lidar

NASA Astrophysics Data System (ADS)

Bohlin, Inka; Olsson, Håkan; Bohlin, Jonas; Granström, Anders

2017-12-01

Massive tree-felling due to root damage is a common fire effect on burnt areas in Scandinavia, but has so far not been analyzed in detail. Here we explore if pre- and post-fire lidar data can be used to estimate the proportion of fallen trees. The study was carried out within a large (14,000 ha) area in central Sweden burnt in August 2014, where we had access to airborne lidar data from both 2011 and 2015. Three data-sets of predictor variables were tested: POST (post-fire lidar metrics), DIF (difference between post- and pre-fire lidar metrics) and combination of those two (POST_DIF). Fractional logistic regression was used to predict the proportion of fallen trees. Training data consisted of 61 plots, where the number of fallen and standing trees was calculated both in the field and with interpretation of drone images. The accuracy of the best model was tested based on 100 randomly selected validation plots with a size of 25 × 25 m. Our results showed that multi-temporal lidar together with field-collected training data can be used for quantifying post-fire tree felling over large areas. Several height-, density- and intensity metrics correlated with the proportion of fallen trees. The best model combined metrics from both datasets (POST_DIF), resulting in a RMSE of 0.11. Results were slightly poorer in the validation plots with RMSE of 0.18 using pixel size of 12.5 m and RMSE of 0.15 using pixel size of 6.25 m. Our model performed least well for stands that had been exposed to high-intensity crown fire. This was likely due to the low amount of echoes from the standing black tree skeletons. Wall-to-wall maps produced with this model can be used for landscape level analysis of fire effects and to explore the relationship between fallen trees and forest structure, soil type, fire intensity or topography.

Fire danger rating and fire behavior prediction in the United States

Treesearch

Patricia L. Andrews

2005-01-01

For the seven year period from 1998 to 2004, an average of almost 79,000 fires per year on U.S. Federal and State land burned a yearly average of over 22,000 km2. An average of 1 billion US dollars was spent on suppression each year by the Federal agencies alone. Variation in climate, vegetation, and population across the U.S. leads to significant differences in the...

On the temperature prediction in a fire escape passage

NASA Astrophysics Data System (ADS)

Casano, G.; Piva, S.

2017-11-01

Fire safety engineering requires a detailed understanding of fire behaviour and of its effects on structures and people. Many factors may condition the fire scenario, as for example, heat transfer between the flame and the boundary structures. Currently advanced numerical codes for the prediction of the fire behaviour are available. However, these solutions often require heavy calculations and long times. In this context analytical solutions can be useful for a fast analysis of simplified schematizations. After that, it is more effective the final utilization of the advanced fire codes. In this contribution, the temperature in a fire escape passage, separated with a thermally resistant wall from a fire room, is analysed. The escape space is included in a building where the neighbouring rooms are at a constant undisturbed temperature. The presence of the neighbouring rooms is considered with an equivalent heat transfer coefficient, in a boundary condition of the third type. An analytical solution is used to predict the temperature distribution during the fire. It allows to obtain useful information on the temperature reached in the escape area in contact with a burning room; it is useful also for a fast choice of the thermal characteristics of a firewall.

Light-frame wall and floor systems : analysis and performance

Treesearch

G. Sherwood; R. C. Moody

1989-01-01

This report describes methods of predicting the performance of light-frame wood structures with emphasis on floor and wall systems. Methods of predicting structural performance, fire safety, and environmental concerns including thermal, moisture, and acoustic performance are addressed in the three major sections.

Firing system modification to alter ash properties for reduction of deposition and slagging under low NOx firing conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, D.; Lewis, R.; Tobiasz, R.

1998-07-01

The composition and properties of ash formed during coal firing have a major impact on boiler performance. Higher ash content in the coal can mean higher costs associated with coal handling, transportation, ash removal and ash disposal along with higher costs due to the increased ash content's deleterious effects on pulverizing, combustion and heat transfer. ABB C-E Services, Inc. has conducted research what might be done to minimize the adverse effects of ash on boiler performance for many years. Recently, ABB C-E Services has studied the effects of firing system modifications on ash composition and properties and the effect thesemore » firing system modifications have on overall furnace performance. The subject of this paper is the impact of the installation of the CFS{trademark} yaw angles were varied and particle samples were collected at the waterwalls for the different yaw angles tested. These ash samples were analyzed for ash composition. The results showed that with a larger CFS{trademark} yaw angle (the air stream directed more towards the boiler walls) the base/acid ratio, iron content and sulfur content of the particle samples collected at the waterwall were reduced. This effect is due to several contributing factors: (1) an oxidizing environment produced by injecting more air toward the walls; and (2) an aerodynamic change which impacts the particle combustion time/temperature history.« less

46 CFR 161.002-12 - Manual fire alarm systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... (a) General. A manual fire alarm system shall consist of a power supply, a control unit on which are... using manually operated fire alarm boxes. (3) Other types as may be developed. (c) Power supply. The power supply shall be as specified for automatic fire detecting system by § 161.002-9. (d) Manual fire...

46 CFR 161.002-12 - Manual fire alarm systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... (a) General. A manual fire alarm system shall consist of a power supply, a control unit on which are... using manually operated fire alarm boxes. (3) Other types as may be developed. (c) Power supply. The power supply shall be as specified for automatic fire detecting system by § 161.002-9. (d) Manual fire...

Fire activity increasing as climate changes

NASA Astrophysics Data System (ADS)

Balcerak, Ernie; Showstack, Randy

2013-01-01

Analysis of images from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) satellites shows that more than 2.5 million hectares were burned in 2012 from January through August in the United States. The amount is less than a record 3.2 million hectares in 2011 but greater than the area burned in 12 of 15 years since satellite monitoring began, scientists reported at the AGU Fall Meeting. With satellites "we can detect fires as they're actively burning," said Louis Giglio of the University of Maryland, College Park, at a press conference on 4 December. "We can also map the cumulative area burned on the landscape after the fire's over." He noted that "2012 has been a particularly big fire year" in the United States.

The Effect of Computer-Based Simulation Training on Fire Ground Incident Commander Decision Making

ERIC Educational Resources Information Center

Hall, Kurt A.

2010-01-01

Since the establishment of the first volunteer fire brigades in the United States, firefighters have lost their lives in fire fighting operations at emergency incidents and live-fire training activities. While there are various reasons for these firefighter deaths and injuries, the United States Fire Administration (2002) reported that many of…

Fires in Idaho and Montana

NASA Technical Reports Server (NTRS)

2002-01-01

2000 continues to be the worst fire season in the United States in decades. By August 8, 2000, fires in Montana and Idaho had burned more than 250,000 acres. Resources were stretched so thin that Army and Marine soldiers were recruited to help fight the fires. President Clinton visited Payette National Forest to lend moral support to the firefighters. Dense smoke from Idaho and western Montana is visible stretching all the way to North and South Dakota in this image from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). The image was taken on August 7, 2000. Although the primary mission of SeaWiFS is to measure the biology of the ocean, it also provides stunning color imagery of the Earth's surface. For more information about fires in the U.S., visit the National Interagency Fire Center. To learn more about using satellites to monitor fires, visit Global Fire Monitoring and New Technology for Monitoring Fires from Space in the Earth Observatory. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

Meta-analysis of avian and small-mammal response to fire severity and fire surrogate treatments in U.S. fire-prone forests.

PubMed

Fontaine, Joseph B; Kennedy, Patricia L

2012-07-01

Management in fire-prone ecosystems relies widely upon application of prescribed fire and/or fire surrogate (e.g., forest thinning) treatments to maintain biodiversity and ecosystem function. Recently, published literature examining wildlife response to fire and fire management has increased rapidly. However, none of this literature has been synthesized quantitatively, precluding assessment of consistent patterns of wildlife response among treatment types. Using meta-analysis, we examined the scientific literature on vertebrate demographic responses to burn severity (low/moderate, high), fire surrogates (forest thinning), and fire and fire surrogate combined treatments in the most extensively studied fire-prone, forested biome (forests of the United States). Effect sizes (magnitude of response) and their 95% confidence limits (response consistency) were estimated for each species-by-treatment combination with two or more observations. We found 41 studies of 119 bird and 17 small-mammal species that examined short-term responses (< or =4 years) to thinning, low/moderate- and high-severity fire, and thinning plus prescribed fire; data on other taxa and at longer time scales were too sparse to permit quantitative assessment. At the stand scale (<50 ha), thinning and low/moderate-severity fire demonstrated similar response patterns in these forests. Combined thinning plus prescribed fire produced a higher percentage of positive responses. High-severity fire provoked stronger responses, with a majority of species possessing higher or lower effect sizes relative to fires of lower severity. In the short term and at fine spatial scales, fire surrogate forest-thinning treatments appear to effectively mimic low/moderate-severity fire, whereas low/moderate-severity fire is not a substitute for high-severity fire. The varied response of taxa to each of the four conditions considered makes it clear that the full range of fire-based disturbances (or their surrogates) is

Fire in Eastern Hardwood Forests through 14,000 Years

Treesearch

Martin A. Spetich; Roger W. Perry; Craig A. Harper; Stacy L. Clark

2011-01-01

Fire helped shape the structure and species composition of hardwood forests of the eastern United States over the past 14,000 years. Periodic fires were common in much of this area prior to European settlement, and fire-resilient species proliferated. Early European settlers commonly adopted Native American techniques of applying fire to the landscape. As the demand...

A fire management simulation model using stochastic arrival times

Treesearch

Eric L. Smith

1987-01-01

Fire management simulation models are used to predict the impact of changes in the fire management program on fire outcomes. As with all models, the goal is to abstract reality without seriously distorting relationships between variables of interest. One important variable of fire organization performance is the length of time it takes to get suppression units to the...

General purpose graphics-processing-unit implementation of cosmological domain wall network evolution.

PubMed

Correia, J R C C C; Martins, C J A P

2017-10-01

Topological defects unavoidably form at symmetry breaking phase transitions in the early universe. To probe the parameter space of theoretical models and set tighter experimental constraints (exploiting the recent advances in astrophysical observations), one requires more and more demanding simulations, and therefore more hardware resources and computation time. Improving the speed and efficiency of existing codes is essential. Here we present a general purpose graphics-processing-unit implementation of the canonical Press-Ryden-Spergel algorithm for the evolution of cosmological domain wall networks. This is ported to the Open Computing Language standard, and as a consequence significant speedups are achieved both in two-dimensional (2D) and 3D simulations.

Fire and forest history at Mount Rushmore.

PubMed

Brown, Peter M; Wienk, Cody L; Symstad, Amy J

2008-12-01

Mount Rushmore National Memorial in the Black Hills of South Dakota is known worldwide for its massive sculpture of four of the United States' most respected presidents. The Memorial landscape also is covered by extensive ponderosa pine (Pinus ponderosa) forest that has not burned in over a century. We compiled dendroecological and forest structural data from 29 plots across the 517-ha Memorial and used fire behavior modeling to reconstruct the historical fire regime and forest structure and compare them to current conditions. The historical fire regime is best characterized as one of low-severity surface fires with occasional (> 100 years) patches (< 100 ha) of passive crown fire. We estimate that only approximately 3.3% of the landscape burned as crown fire during 22 landscape fire years (recorded at > or = 25% of plots) between 1529 and 1893. The last landscape fire was in 1893. Mean fire intervals before 1893 varied depending on spatial scale, from 34 years based on scar-to-scar intervals on individual trees to 16 years between landscape fire years. Modal fire intervals were 11-15 years and did not vary with scale. Fire rotation (the time to burn an area the size of the study area) was estimated to be 30 years for surface fire and 800+ years for crown fire. The current forest is denser and contains more small trees, fewer large trees, lower canopy base heights, and greater canopy bulk density than a reconstructed historical (1870) forest. Fire behavior modeling using the NEXUS program suggests that surface fires would have dominated fire behavior in the 1870 forest during both moderate and severe weather conditions, while crown fire would dominate in the current forest especially under severe weather. Changes in the fire regime and forest structure at Mount Rushmore parallel those seen in ponderosa pine forests from the southwestern United States. Shifts from historical to current forest structure and the increased likelihood of crown fire justify the need for

46 CFR 107.257 - Testing of fire hose.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Testing of fire hose. 107.257 Section 107.257 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.257 Testing of fire hose. Each fire hose must be subjected to a...

46 CFR 107.257 - Testing of fire hose.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Testing of fire hose. 107.257 Section 107.257 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.257 Testing of fire hose. Each fire hose must be subjected to a...

46 CFR 107.257 - Testing of fire hose.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Testing of fire hose. 107.257 Section 107.257 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.257 Testing of fire hose. Each fire hose must be subjected to a...

46 CFR 107.257 - Testing of fire hose.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Testing of fire hose. 107.257 Section 107.257 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.257 Testing of fire hose. Each fire hose must be subjected to a...

46 CFR 107.257 - Testing of fire hose.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Testing of fire hose. 107.257 Section 107.257 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.257 Testing of fire hose. Each fire hose must be subjected to a...

Impacts of fire and fire surrogate treatments on ecosystem nitrogen storage patterns: similarities and differences between forests of eastern and western North America

Treesearch

R.E.J. Boerner; J. Huang; S.C. Hart

2009-01-01

The Fire and Fire Surrogates (FFS) network is composed of 12 forest sites that span the continental United States, all of which historically had frequent low-severity fire. The goal of the FFS study was to assess the efficacy of three management treatments (prescribed fire, mechanical thinning, and their combination) in reducing wildfire hazard and increasing ecosystem...

Wood crib fire free burning test in ISO room

NASA Astrophysics Data System (ADS)

Qiang, Xu; Griffin, Greg; Bradbury, Glenn; Dowling, Vince

2006-04-01

In the research of application potential of water mist fire suppression system for fire fighting in train luggage carriage, a series of experiments were conducted in ISO room on wood crib fire with and without water mist actuation. The results of free burn test without water mist suppression are used as reference in evaluating the efficiency of water mist suppression system. As part of the free burn test, several tests have been done under the hood of ISO room to calibrate the size of the crib fire and these tests can also be used in analyzing the wall effect in room fire hazard. In these free burning experiments, wood cribs of four sizes under the hood were tested. The temperature of crib fire, heat flux around the fire, gas concentration in hood of ISO room were measured in the experiments and two sets of thermal imaging system were used to get the temperature distribution and the typical shape of the free burning flames. From the experiments, the radiation intensity in specific positions around the fire, the effective heat of combustion, mass loss, oxygen consumption rate for different sizes of fire, typical structure of the flame and self extinguishment time was obtained for each crib size.

Fire risk in California

NASA Astrophysics Data System (ADS)

Peterson, Seth Howard

Fire is an integral part of ecosystems in the western United States. Decades of fire suppression have led to (unnaturally) large accumulations of fuel in some forest communities, such as the lower elevation forests of the Sierra Nevada. Urban sprawl into fire prone chaparral vegetation in southern California has put human lives at risk and the decreased fire return intervals have put the vegetation community at risk of type conversion. This research examines the factors affecting fire risk in two of the dominant landscapes in the state of California, chaparral and inland coniferous forests. Live fuel moisture (LFM) is important for fire ignition, spread rate, and intensity in chaparral. LFM maps were generated for Los Angeles County by developing and then inverting robust cross-validated regression equations from time series field data and vegetation indices (VIs) and phenological metrics from MODIS data. Fire fuels, including understory fuels which are not visible to remote sensing instruments, were mapped in Yosemite National Park using the random forests decision tree algorithm and climatic, topographic, remotely sensed, and fire history variables. Combining the disparate data sources served to improve classification accuracies. The models were inverted to produce maps of fuel models and fuel amounts, and these showed that fire fuel amounts are highest in the low elevation forests that have been most affected by fire suppression impacting the natural fire regime. Wildland fires in chaparral commonly burn in late summer or fall when LFM is near its annual low, however, the Jesusita Fire burned in early May of 2009, when LFM was still relatively high. The HFire fire spread model was used to simulate the growth of the Jesusita Fire using LFM maps derived from imagery acquired at the time of the fire and imagery acquired in late August to determine how much different the fire would have been if it had occurred later in the year. Simulated fires were 1.5 times larger

Surgical fires: a patient safety perspective.

PubMed

2006-02-01

A surgical fire is a fire that occurs on or in a surgical patient. Such fires are rare--they occur in only an extremely small percentage of surgical cases. Nevertheless, the actual number of incidents that occur each year may surprise many healthcare professionals. ECRI estimates that 50 to 100 or more surgical fires occur each year in the United States alone. And such fires can have devastating consequences, not only for the patient, but also for the surgical staff and for the healthcare facility. Fortunately, through awareness of the hazards-and with emphasis placed on following safe practices-virtually all surgical fires can be prevented. Thus, it's important that surgical fire safety be incorporated into formal patient safety initiatives. In this article, we describe a few surgical fire patient safety initiatives that have been instituted in recent years. In addition, we describe in detail the causes of surgical fires and the preventive measures that are available for healthcare personnel to follow. In addition, we review how staff should respond in the event of a surgical fire.

IET. Stack interior. Masons lay fire brick liner, leaving air ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

IET. Stack interior. Masons lay fire brick liner, leaving air layer between bricks and concrete wall. Date: May 20, 1955. INEEL negative no. 55-1306 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Low-cost, portable fire hose tester

NASA Technical Reports Server (NTRS)

Jocke, R. F.; Miller, R. E.

1975-01-01

Availability of pumping unit permits scheduling and performing required periodic hose tests in proper manner while retaining full fire equipment readiness. Use of pumping unit preserves operating life and capability of pumper truck.

46 CFR 108.407 - Detectors for electric fire detection system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Detectors for electric fire detection system. 108.407... DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.407 Detectors for electric fire detection system. (a) Each detector in an electric fire detection system must be located where— (1) No...

Design and implementation of the monitoring system for underground coal fires in Xinjiang region, China

NASA Astrophysics Data System (ADS)

Li-bo, Dang; Jia-chun, Wu; Yue-xing, Liu; Yuan, Chang; Bin, Peng

2017-04-01

Underground coal fire (UCF) is serious in Xinjiang region of China. In order to deal with this problem efficiently, a UCF monitoring System, which is based on the use of wireless communication technology and remote sensing images, was designed and implemented by Xinjiang Coal Fire Fighting Bureau. This system consists of three parts, i.e., the data collecting unit, the data processing unit and the data output unit. For the data collecting unit, temperature sensors and gas sensors were put together on the sites with depth of 1.5 meter from the surface of coal fire zone. Information on these sites' temperature and gas was transferred immediately to the data processing unit. The processing unit was developed by coding based on GIS software. Generally, the processed datum were saved in the computer by table format, which can be displayed on the screen as the curve. Remote sensing image for each coal fire was saved in this system as the background for each monitoring site. From the monitoring data, the changes of the coal fires were displayed directly. And it provides a solid basis for analyzing the status of coal combustion of coal fire, the gas emission and possible dominant direction of coal fire propagation, which is helpful for making-decision of coal fire extinction.

6. View of mill wall ruins looking E showing arched ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. View of mill wall ruins looking E showing arched openings where fuel was fed to fire Jamaican Train. - Hacienda Azucarera La Esperanza, Mill (Ruins), 2.65 miles North of PR Route 2 Bridge Over Manati River, Manati, Manati Municipio, PR

A fundamental look at fire spread in California chaparral

Treesearch

David R. Weise; Thomas Fletcher; Larry Baxter; Shankar Mahalingam; Xiangyang Zhou; Patrick Pagni; Rod Linn; Bret Butler

2004-01-01

The USDA Forest Service National Fire Plan funded a research program to study fire spread in live fuels of the southwestern United States. In the U.S. current operational fire spread models do not distinguish between live and dead fuels in a sophisticated manner because the study of live fuels has been limited. The program is experimentally examining fire spread at 3...

Wall Interference Study of the NTF Slotted Tunnel Using Bodies of Revolution Wall Signature Data

NASA Technical Reports Server (NTRS)

Iyer, Venkit; Kuhl, David D.; Walker, Eric L.

2004-01-01

This paper is a description of the analysis of blockage corrections for bodies of revolution for the slotted-wall configuration of the National Transonic Facility (NTF) at the NASA Langley Research Center (LaRC). A wall correction method based on the measured wall signature is used. Test data from three different-sized blockage bodies and four wall ventilation settings were analyzed at various Mach numbers and unit Reynolds numbers. The results indicate that with the proper selection of the boundary condition parameters, the wall correction method can predict blockage corrections consistent with the wall measurements for Mach numbers as high as 0.95.

Induced superhydrophobic and antimicrobial character of zinc metal modified ceramic wall tile surfaces

NASA Astrophysics Data System (ADS)

Özcan, Selçuk; Açıkbaş, Gökhan; Çalış Açıkbaş, Nurcan

2018-04-01

Hydrophobic surfaces are also known to have antimicrobial effect by restricting the adherence of microorganisms. However, ceramic products are produced by high temperature processes resulting in a hydrophilic surface. In this study, an industrial ceramic wall tile glaze composition was modified by the inclusion of metallic zinc powder in the glaze suspension applied on the pre-sintered wall tile bodies by spraying. The glazed tiles were gloss fired at industrially applicable peak temperatures ranging from 980 °C to 1100 °C. The fired tile surfaces were coated with a commercial fluoropolymer avoiding water absorption. The surfaces were characterized with SEM, EDS, XRD techniques, roughness, sessile water drop contact angle, surface energy measurements, and standard antimicrobial tests. The surface hydrophobicity and the antimicrobial activity results were compared with that of unmodified, uncoated gloss fired wall tiles. A superhydrophobic contact angle of 150° was achieved at 1000 °C peak temperature due to the formation of micro-structured nanocrystalline zinc oxide granules providing a specific surface topography. At higher peak temperatures the hydrophobicity was lost as the specific granular surface topography deteriorated with the conversion of zinc oxide granules to the ubiquitous willemite crystals embedded in the glassy matrix. The antimicrobial efficacy also correlated with the hydrophobic character.

Ultraviolet Source For Testing Hydrogen-Fire Detectors

NASA Technical Reports Server (NTRS)

Hall, Gregory A.; Larson, William E.; Youngquist, Robert C.; Moerk, John S.; Haskell, William D.; Cox, Robert B.; Polk, Jimmy D.; Stout, Stephen J.; Strobel, James P.

1995-01-01

Hand-held portable unit emits ultraviolet light similar to that emitted by hydrogen burning in air. Developed for use in testing optoelectronic hydrogen-fire detectors, which respond to ultraviolet light at wavelengths from 180 to 240 nanometers. Wavelength range unique in that within it, hydrogen fires emit small but detectable amounts of radiation, light from incandescent lamps and Sun almost completely absent, and air sufficiently transmissive to enable detection of hydrogen fire from distance. Consequently, this spectral region favorable for detecting hydrogen fires while minimizing false alarms.

5. DETAIL VIEW OF OLD, PUNCHTYPE MASTER FIRE ALARM SYSTEM, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. DETAIL VIEW OF OLD, PUNCH-TYPE MASTER FIRE ALARM SYSTEM, LOCATED ON S WALL OF ENGINE STORAGE ROOM; LOOKING S. (Ceronie and Ryan) - Watervliet Arsenal, Building No. 22, Westervelt Avenue & Buffington Street, Watervliet, Albany County, NY

124. FIRE ALARM SYSTEM PANEL AT WEST SIDE OF SOUTH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

124. FIRE ALARM SYSTEM PANEL AT WEST SIDE OF SOUTH WALL, TRANSFORMER ROOM (112), LSB (BLDG. 770) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

Fire and Smoke Model Evaluation Experiment: Coordination of a study to improve smoke modeling for fire operations within the United States

NASA Astrophysics Data System (ADS)

French, N. H. F.; Ottmar, R. D.; Brown, T. J.; Larkin, N. K.

2017-12-01

The Fire and Smoke Model Evaluation Experiment (FASMEE) is an integrative research effort to identify and collect critical measurements to improve operational wildland fire and smoke prediction systems. FASMEE has two active phases and one suggested phase. Phase 1 is the analysis and planning process to assess the current state of fire-plume-smoke modeling and to determine the critical measurements required to evaluate and improve these operational fire and smoke models. As the major deliverable for Phase 1, a study plan has been completed that describes the measurement needs, field campaigns, and command, safety and air space de-confliction plans necessary to complete the FASMEE project. Phase 2 is a set of field campaigns to collect data during 2019-2022. Future Improvements would be a set of analyses and model improvements based on the data collected within Phase 2 that is dependent on identifying future funding sources. In this presentation, we will review the FASMEE Study Plan and detailed measurements and conditions expected for the four to five proposed research burns. The recommended measurements during Phase 2 span the four interrelated disciplines of FASMEE: fuels and consumption, fire behavior and energy, plume dynamics and meteorology, and smoke emissions, chemistry, and transport. Fuel type, condition, and consumption during wildland fire relates to several fire impacts including radiative heating, which provides the energy that drives fire dynamics. Local-scale meteorology is an important factor which relates to atmospheric chemistry, dispersion, and transport. Plume dynamics provide the connection between fire behavior and far-field smoke dispersion, because it determines the vertical distribution of the emissions. Guided by the data needs and science questions generated during Phase 1, three wildland fire campaigns were selected. These included the western wildfire campaign (rapid deployment aimed at western wildfires supporting NOAA, NASA, and NSF

46 CFR 108.413 - Fusible element fire detection system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Fusible element fire detection system. 108.413 Section 108.413 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.413 Fusible element fire detection system...

46 CFR 108.413 - Fusible element fire detection system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Fusible element fire detection system. 108.413 Section 108.413 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.413 Fusible element fire detection system...

46 CFR 108.413 - Fusible element fire detection system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Fusible element fire detection system. 108.413 Section 108.413 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.413 Fusible element fire detection system...

46 CFR 108.413 - Fusible element fire detection system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fusible element fire detection system. 108.413 Section 108.413 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.413 Fusible element fire detection system...

Measuring wildland fire fighter performance with wearable technology.

PubMed

Parker, Richard; Vitalis, Antonios; Walker, Robyn; Riley, David; Pearce, H Grant

2017-03-01

Wildland (rural) fire fighting is a physically demanding and hazardous occupation. An observational study was conducted to explore the use of new technologies for the field study of fire fighters at wildfires and to understand the work pressures of wildland fire fighting. The research was carried out with two fire fighters at real fires wearing microphones, miniature video cameras, heart rate monitors and GPS units to record their actions and location at wildfire events. The fire fighters were exposed to high physiological workloads (heart rates of up to 180 beats per minute) and walked considerable distances at the fires. Results from this study have been used in presentations to fire fighters and non-operational fire personnel to understand the pressures fire fighters are under and how others complete the fire fighting tasks. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fuels planning: science synthesis and integration; forest structure and fire hazard fact sheet 06: Guide to fuel treatments in dry forests of the Western United States: assessing forest structure and fire hazard

Treesearch

Rocky Mountain Research Station USDA Forest Service

2005-01-01

The Guide to Fuel Treatments analyzes a range of potential silvicultural thinnings and surface fuel treatments for 25 representative dry-forest stands in the Western United States. The guide provides quantitative guidelines and visualization for treatment based on scientific principles identified for reducing potential crown fires. This fact sheet identifies the...

Climate change and forest fires.

PubMed

Flannigan, M D; Stocks, B J; Wotton, B M

2000-11-15

This paper addresses the impacts of climate change on forest fires and describes how this, in turn, will impact on the forests of the United States. In addition to reviewing existing studies on climate change and forest fires we have used two transient general circulation models (GCMs), namely the Hadley Centre and the Canadian GCMs, to estimate fire season severity in the middle of the next century. Ratios of 2 x CO2 seasonal severity rating (SSR) over present day SSR were calculated for the means and maximums for North America. The results suggest that the SSR will increase by 10-50% over most of North America; although, there are regions of little change or where the SSR may decrease by the middle of the next century. Increased SSRs should translate into increased forest fire activity. Thus, forest fires could be viewed as an agent of change for US forests as the fire regime will respond rapidly to climate warming. This change in the fire regime has the potential to overshadow the direct effects of climate change on species distribution and migration.

Simulating fuel treatment effects in dry forests of the western United States: testing the principles of a fire-safe forest

Treesearch

Morris C. Johnson; Maureen C Kennedy; David L. Peterson

2011-01-01

We used the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE-FVS) to simulate fuel treatment effects on stands in low- to midelevation dry forests (e.g., ponderosa pine (Pinus ponderosa Dougl. ex. P. & C. Laws.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) of the western United States. We...

Co-firing switchgrass in a 50 MW pulverized coal boiler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ragland, K.W.; Aerts, D.J.; Weiss, C.

1996-12-31

Switchgrass is being co-fired with pulverized coal in a 50 MW wall-fired, radiant boiler at MG&E`s Blount Street generating station. Shredded switchgrass is fed to a hammermill onto a live bottom storage bunker. Twin screw augers move the switchgrass onto a belt conveyor which leads to a rotary air lock valve and through a pressurized pipe to the boiler where it is injected into the furnace at two points between first and second level coal burners. The main objective of the project is to evaluate the boiler performance, slagging behavior, and emissions of the co-fired switchgrass at replacement of ratesmore » of up to 20% by mass (13% by heat input). Initial co-firing tests to examine fuel handling and feeding, combustion behavior, boiler response and emissions are favorable. In November a 100 hour co-fire test is planned.« less

77 FR 45967 - National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-02

... Electric Utility Steam Generating Units and Standards of Performance for Fossil-Fuel-Fired Electric Utility...-fired Electric Utility Steam Generating Units and Standards of Performance for Fossil-Fuel-Fired...

Updated logistic regression equations for the calculation of post-fire debris-flow likelihood in the western United States

USGS Publications Warehouse

Staley, Dennis M.; Negri, Jacquelyn A.; Kean, Jason W.; Laber, Jayme L.; Tillery, Anne C.; Youberg, Ann M.

2016-06-30

Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can generate dangerous flash floods and debris flows. To reduce public exposure to hazard, the U.S. Geological Survey produces post-fire debris-flow hazard assessments for select fires in the western United States. We use publicly available geospatial data describing basin morphology, burn severity, soil properties, and rainfall characteristics to estimate the statistical likelihood that debris flows will occur in response to a storm of a given rainfall intensity. Using an empirical database and refined geospatial analysis methods, we defined new equations for the prediction of debris-flow likelihood using logistic regression methods. We showed that the new logistic regression model outperformed previous models used to predict debris-flow likelihood.

The 2000 fire season: lightning-caused fires.

Treesearch

Miriam L. Rorig; Sue A. Ferguson

2002-01-01

A large number of lightning-caused fires burned across the western United States during the summer of 2000. In a previous study, the authors determined that a simple index of low-level moisture (85-kPa dewpoint depression) and instability (85–50-kPa temperature difference) from the Spokane, Washington, upper-air soundings was very useful for indicating the likelihood...

75 FR 66735 - National Fire Protection Association (NFPA): Request for Comments on NFPA's Codes and Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-29

... Ignitibility of Exterior Wall Assemblies Using a Radiant Heat Energy Source. NFPA 269 Standard Test Method P... for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen Consumption... Plastic Insulation. NFPA 285 Standard Fire Test P Method for Evaluation of Fire Propagation...

Cast Coil Transformer Fire Susceptibility and Reliability Study

DTIC Science & Technology

1991-04-01

transformers reduce risk to the user compared to liquid-filled units, eliminate environmental impacts, are more efficient than most transformer designs, and...filled units, eliminate environmental impacts, arc more efficient than most transformer designs, and add minimal risk to the facility in a fire situation...add minimal risk to the facility in a fire situation. Cast coil transformers have a long record of operation and have proven to be reliable and

46 CFR 28.820 - Fire pumps, fire mains, fire hydrants, and fire hoses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Fire pumps, fire mains, fire hydrants, and fire hoses... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.820 Fire pumps, fire mains, fire hydrants, and fire hoses. (a) Each vessel must be equipped with a self-priming, power driven fire...

How can prescribed burning and harvesting restore shortleaf pine-oak woodland at the landscape scale in central United States? Modeling joint effects of harvest and fire regimes

Treesearch

Wenchi Jin; Hong S. He; Stephen R. Shifley; Wen J. Wang; John M. Kabrick; Brian K. Davidson

2018-01-01

Historical fire regimes in the central United States maintained open-canopy shortleaf pine-oak woodlands on xeric sites. Following large-scale harvest and fire suppression, those woodlands grew denser with more continuous canopy cover, and they gained mesic species at the expense of shortleaf pine. There is high interest in restoring shortleaf pine-oak woodlands; most...

Status of native fishes in the western United States and issues for fire and fuels management

USGS Publications Warehouse

Rieman, B.; Lee, D.; Burns, D.; Gresswell, Robert E.; Young, M.; Stowell, R.; Rinne, J.; Howell, P.

2003-01-01

Conservation of native fishes and changing patterns in wildfire and fuels are defining challenges for managers of forested landscapes in the western United States. Many species and populations of native fishes have declined in recorded history and some now occur as isolated remnants of what once were larger more complex systems. Land management activities have been viewed as one cause of this problem. Fires also can have substantial effects on streams and riparian systems and may threaten the persistence of some populations of fish, particularly those that are small and isolated. Despite that, major new efforts to actively manage fires and fuels in forests throughout the region may be perceived as a threat rather than a benefit to conservation of native fishes and their habitats. The management of terrestrial and aquatic resources has often been contentious, divided among a variety of agencies with different goals and mandates. Management of forests, for example, has generally been viewed as an impact on aquatic systems. Implementation of the management-regulatory process has reinforced a uniform approach to mitigate the threats to aquatic species and habitats that may be influenced by management activities. The problems and opportunities, however, are not the same across the landscapes of interest. Attempts to streamline the regulatory process often search for generalized solutions that may oversimplify the complexity of natural systems. Significant questions regarding the influence of fire on aquatic ecosystems, changing fire regimes, and the effects of fire-related management remain unresolved and contribute to the uncertainty. We argue that management of forests and fishes can be viewed as part of the same problem, that of conservation and restoration of the natural processes that create diverse and productive ecosystems. We suggest that progress toward more integrated management of forests and native fishes will require at least three steps: (1) better

46 CFR 108.404 - Selection of fire detection system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Selection of fire detection system. 108.404 Section 108.404 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.404 Selection of fire detection system. (a) If a...

46 CFR 107.251 - Testing of the fire main.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Testing of the fire main. 107.251 Section 107.251 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.251 Testing of the fire main. Each fire main...

46 CFR 107.251 - Testing of the fire main.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Testing of the fire main. 107.251 Section 107.251 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.251 Testing of the fire main. Each fire main...

46 CFR 108.404 - Selection of fire detection system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Selection of fire detection system. 108.404 Section 108.404 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.404 Selection of fire detection system. (a) If a...

46 CFR 108.404 - Selection of fire detection system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Selection of fire detection system. 108.404 Section 108.404 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.404 Selection of fire detection system. (a) If a...

46 CFR 107.251 - Testing of the fire main.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Testing of the fire main. 107.251 Section 107.251 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.251 Testing of the fire main. Each fire main...

46 CFR 108.404 - Selection of fire detection system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Selection of fire detection system. 108.404 Section 108.404 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.404 Selection of fire detection system. (a) If a...

46 CFR 107.251 - Testing of the fire main.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Testing of the fire main. 107.251 Section 107.251 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.251 Testing of the fire main. Each fire main...

46 CFR 107.251 - Testing of the fire main.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Testing of the fire main. 107.251 Section 107.251 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS INSPECTION AND CERTIFICATION Inspection and Certification § 107.251 Testing of the fire main. Each fire main...

46 CFR 161.002-12 - Manual fire alarm systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the control unit and terminating at manual fire alarm boxes. Power failure alarm devices may be... specifically approved. (b) Types. Manual fire alarm systems shall be one of the following types, or a... using manually operated fire alarm boxes. (3) Other types as may be developed. (c) Power supply. The...

46 CFR 161.002-12 - Manual fire alarm systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the control unit and terminating at manual fire alarm boxes. Power failure alarm devices may be... specifically approved. (b) Types. Manual fire alarm systems shall be one of the following types, or a... using manually operated fire alarm boxes. (3) Other types as may be developed. (c) Power supply. The...

46 CFR 161.002-12 - Manual fire alarm systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the control unit and terminating at manual fire alarm boxes. Power failure alarm devices may be... specifically approved. (b) Types. Manual fire alarm systems shall be one of the following types, or a... using manually operated fire alarm boxes. (3) Other types as may be developed. (c) Power supply. The...

Developing the U.S. Wildland Fire Decision Support System

Treesearch

Erin Noonan-Wright; Tonja S. Opperman; Mark A. Finney; Tom Zimmerman; Robert C. Seli; Lisa M. Elenz; David E. Calkin; John R. Fiedler

2011-01-01

A new decision support tool, the Wildland Fire Decision Support System (WFDSS) has been developed to support risk-informed decision-making for individual fires in the United States. WFDSS accesses national weather data and forecasts, fire behavior prediction, economic assessment, smoke management assessment, and landscape databases to efficiently formulate and apply...

Evaluated community fire safety interventions in the United States: a review of current literature.

PubMed

Ta, Van M; Frattaroli, Shannon; Bergen, Gwendolyn; Gielen, Andrea Carlson

2006-06-01

The purpose of the study was to assess the state of fire prevention research, provide an updated synthesis of evaluated fire prevention programs, and discuss the role of fire fighters and data systems in prevention efforts. The review included all evaluations of U.S. based fire prevention interventions published between January 1998 and September 2004 and any earlier articles about U.S. fire prevention interventions not included in two prior review articles. We retrieved information from each identified study including evaluation findings, involvement of fire service personnel and use of existing data systems. We identified twelve articles: seven reported on smoke alarm interventions, three on multi-faceted programs, and two other programs. Five programs involved fire service personnel in the design, implementation, and/or evaluation, and three used existing data systems. Studies reviewed suggest that canvassing and smoke alarm installations are the most effective means of distributing alarms and increasing the functional status of distributed alarms. The functionality of smoke alarms, an issue noted in earlier reviews, remains a problem. Programs involving partnerships with fire departments have indicated success in preventing fires and deaths, improving smoke alarm ownership and functional status, and improving children's fire safety knowledge. Using existing data systems to target and to evaluate interventions was effective. In the years since prior reviews, some improvements in the rigor of evaluation designs have been made, but there is still a need for high quality evaluations that will inform fire injury prevention efforts.

Climate and forest fires in Montana and northern Idaho, 1909-1919

Treesearch

J. A. Larsen; C. C. Delavan

1922-01-01

The present report is a result of the study of the relation between climate and forest fires in Montana and northern Idaho. This region is designated as District I of the United States Forest Service. The data used are the weather records of the United States Weather Bureau for the regular and cooperative stations, and the detail fire reports of the United States...

Ultrafine and respirable particle exposure during vehicle fire suppression.

PubMed

Evans, Douglas E; Fent, Kenneth W

2015-10-01

Vehicle fires are a common occurrence, yet few studies have reported exposures associated with burning vehicles. This article presents an assessment of firefighters' potential for ultrafine and respirable particle exposure during vehicle fire suppression training. Fires were initiated within the engine compartment and passenger cabins of three salvaged vehicles, with subsequent water suppression by fire crews. Firefighter exposures were monitored with an array of direct reading particle and air quality instruments. A flexible metallic duct and blower drew contaminants to the instrument array, positioned at a safe distance from the burning vehicles, with the duct inlet positioned at the nozzle operator's shoulder. The instruments measured the particle number, active surface area, respirable particle mass, photoelectric response, aerodynamic particle size distributions, and air quality parameters. Although vehicle fires were suppressed quickly (<10 minutes), firefighters may be exposed to short duration, high particle concentration episodes during fire suppression, which are orders of magnitude greater than the ambient background concentration. A maximum transient particle concentration of 1.21 × 10(7) particles per cm(3), 170 mg m(-3) respirable particle mass, 4700 μm(2) cm(-3) active surface area and 1400 (arbitrary units) in photoelectric response were attained throughout the series of six fires. Expressed as fifteen minute time-weighted averages, engine compartment fires averaged 5.4 × 10(4) particles per cm(3), 0.36 mg m(-3) respirable particle mass, 92 μm(2) cm(-3) active particle surface area and 29 (arbitrary units) in photoelectric response. Similarly, passenger cabin fires averaged 2.04 × 10(5) particles per cm(3), 2.7 mg m(-3) respirable particle mass, 320 μm(2) cm(-3) active particle surface area, and 34 (arbitrary units) in photoelectric response. Passenger cabin fires were a greater potential source of exposure than engine compartment fires. The

Ultrafine and respirable particle exposure during vehicle fire suppression

PubMed Central

Fent, Kenneth W.

2015-01-01

Vehicle fires are a common occurrence, yet few studies have reported exposures associated with burning vehicles. This article presents an assessment of firefighters’ potential for ultrafine and respirable particle exposure during vehicle fire suppression training. Fires were initiated within the engine compartment and passenger cabins of three salvaged vehicles, with subsequent water suppression by fire crews. Firefighter exposures were monitored with an array of direct reading particle and air quality instruments. A flexible metallic duct and blower drew contaminants to the instrument array, positioned at a safe distance from the burning vehicles, with the duct inlet positioned at the nozzle operator’s shoulder. The instruments measured the particle number, active surface area, respirable particle mass, photoelectric response, aerodynamic particle size distributions, and air quality parameters. Although vehicle fires were suppressed quickly (<10 minutes), firefighters may be exposed to short duration, high particle concentration episodes during fire suppression, which are orders of magnitude greater than the ambient background concentration. A maximum transient particle concentration of 1.21 × 107 particles per cm3, 170 mg m−3 respirable particle mass, 4700 μm2 cm−3 active surface area and 1400 (arbitrary units) in photoelectric response were attained throughout the series of six fires. Expressed as fifteen minute time-weighted averages, engine compartment fires averaged 5.4 × 104 particles per cm3, 0.36 mg m−3 respirable particle mass, 92 μm2 cm−3 active particle surface area and 29 (arbitrary units) in photoelectric response. Similarly, passenger cabin fires averaged 2.04 × 105 particles per cm3, 2.7 mg m−3 respirable particle mass, 320 μm2 cm−3 active particle surface area, and 34 (arbitrary units) in photoelectric response. Passenger cabin fires were a greater potential source of exposure than engine compartment fires. The wind direction

Estimates of CO2 from fires in the United States: implications for carbon management.

PubMed

Wiedinmyer, Christine; Neff, Jason C

2007-11-01

Fires emit significant amounts of CO2 to the atmosphere. These emissions, however, are highly variable in both space and time. Additionally, CO2 emissions estimates from fires are very uncertain. The combination of high spatial and temporal variability and substantial uncertainty associated with fire CO2 emissions can be problematic to efforts to develop remote sensing, monitoring, and inverse modeling techniques to quantify carbon fluxes at the continental scale. Policy and carbon management decisions based on atmospheric sampling/modeling techniques must account for the impact of fire CO2 emissions; a task that may prove very difficult for the foreseeable future. This paper addresses the variability of CO2 emissions from fires across the US, how these emissions compare to anthropogenic emissions of CO2 and Net Primary Productivity, and the potential implications for monitoring programs and policy development. Average annual CO2 emissions from fires in the lower 48 (LOWER48) states from 2002-2006 are estimated to be 213 (+/- 50 std. dev.) Tg CO2 yr-1 and 80 (+/- 89 std. dev.) Tg CO2 yr-1 in Alaska. These estimates have significant interannual and spatial variability. Needleleaf forests in the Southeastern US and the Western US are the dominant source regions for US fire CO2 emissions. Very high emission years typically coincide with droughts, and climatic variability is a major driver of the high interannual and spatial variation in fire emissions. The amount of CO2 emitted from fires in the US is equivalent to 4-6% of anthropogenic emissions at the continental scale and, at the state-level, fire emissions of CO2 can, in some cases, exceed annual emissions of CO2 from fossil fuel usage. The CO2 released from fires, overall, is a small fraction of the estimated average annual Net Primary Productivity and, unlike fossil fuel CO2 emissions, the pulsed emissions of CO2 during fires are partially counterbalanced by uptake of CO2 by regrowing vegetation in the decades

Grizzly Gulch Fire, South Dakota

NASA Technical Reports Server (NTRS)

2002-01-01

Burning next door to the South Dakota towns of Deadwood and Lead, the Grizzly Gulch fire forced the evacuation of many residents in the first week of July, 2002. In addition, smoke closed many of the roads in the area. At the time the fire's behavior was extreme, with 'torching, spotting, and running.' In other words, the fire was primarily burning along the ground, with entire trees occasionally erupting into flame (torching). At the same time, burning embers were being thrown ahead of the fire (spotting). In some areas the fire was spreading from the crown of one tree to another (running). (This glossary of fire terms has a good list of definitions) The above image shows the fire on the morning of July 1, 2002. Actively burning areas, concentrated on the east (right) side of the fire, are colored red and orange. Dark red areas indicate burn scars, while forest and other vegetation appears green. The exposed rock of the Homestake gold mine, now the National Underground Science Laboratory, is pinkish-brown. The total extent of the fire is oulined in yellow. The image was acquired by the Enhanced Thematic Mapper plus (ETM+) aboard the Landsat 7 satellite. More news about current wildfires in the United States is available from the National Fire Information Center. Image provided by the USGS EROS Data Center Satellite Systems Branch.

Fire severity classification: Uses and abuses

Treesearch

Theresa B. Jain; Russell T. Graham

2003-01-01

Burn severity (also referred to as fire severity) is not a single definition, but rather a concept and its classification is a function of the measured units unique to the system of interest. The systems include: flora and fauna, soil microbiology and hydrologic processes, atmospheric inputs, fire management, and society. Depending on the particular system of interest...

Risk of commercial truck fires in the United States : an exploratory data analysis

DOT National Transportation Integrated Search

2012-06-29

Large trucks are involved in only 8 percent of fatal crashes per year, but 17 percent of fatal fires. The scope of the current body of research is limited. Studies have treated truck fires generally as a subset of vehicle fires or in their own right ...

Estimating canopy bulk density and canopy base height for conifer stands in the interior Western United States using the Forest Vegetation Simulator Fire and Fuels Extension.

Treesearch

Seth Ex; Frederick Smith; Tara Keyser; Stephanie Rebain

2017-01-01

The Forest Vegetation Simulator Fire and Fuels Extension (FFE-FVS) is often used to estimate canopy bulk density (CBD) and canopy base height (CBH), which are key indicators of crown fire hazard for conifer stands in the Western United States. Estimated CBD from FFE-FVS is calculated as the maximum 4 m running mean bulk density of predefined 0.3 m thick canopy layers (...

Assessment of wildland fire impacts on watershed annual water yield: Analytical framework and case studies in the United States

Treesearch

Dennis W. Hallema; Ge Sun; Peter V. Caldwell; Steve Norman; Erika Cohen Mack; Yongqiang Liu; Eric J. Ward; Steve McNulty

2016-01-01

More than 50% of water supplies in the conterminous United States originate on forestland or rangeland, and are potentially under increasing stress as a result of larger and more severe wildfires. Little is known however about the long-term impacts of fire on annual water yield, and the role of climate variability within this context. We here propose a framework for...

Hierarchical control of motor units in voluntary contractions.

PubMed

De Luca, Carlo J; Contessa, Paola

2012-01-01

For the past five decades there has been wide acceptance of a relationship between the firing rate of motor units and the afterhyperpolarization of motoneurons. It has been promulgated that the higher-threshold, larger-soma, motoneurons fire faster than the lower-threshold, smaller-soma, motor units. This relationship was based on studies on anesthetized cats with electrically stimulated motoneurons. We questioned its applicability to motor unit control during voluntary contractions in humans. We found that during linearly force-increasing contractions, firing rates increased as exponential functions. At any time and force level, including at recruitment, the firing rate values were inversely related to the recruitment threshold of the motor unit. The time constants of the exponential functions were directly related to the recruitment threshold. From the Henneman size principle it follows that the characteristics of the firing rates are also related to the size of the soma. The "firing rate spectrum" presents a beautifully simple control scheme in which, at any given time or force, the firing rate value of earlier-recruited motor units is greater than that of later-recruited motor units. This hierarchical control scheme describes a mechanism that provides an effective economy of force generation for the earlier-recruited lower force-twitch motor units, and reduces the fatigue of later-recruited higher force-twitch motor units-both characteristics being well suited for generating and sustaining force during the fight-or-flight response.

Reintroduction of Fire into Fire-Dependent Ecosystems: Some Southern Examples

Treesearch

Dale Wade; George Custer; Jim Thorsen; Paul Kaskey; John Kush; Bill Twomey; Doug Voltolina

1997-01-01

Natural resource problems associated with, or resulting from, attempted fire exclusion are challenging managers across the United States. Critical issues range from epidemic insect and disease conditions to species extirpations. Southern burners continue to demonstrate that seemingly insurmountable constraints can be overcome through commitment and cooperation, and...

Fire social science research from the Pacific Southwest research station: studies supported by national fire plan funds

Treesearch

Deborah J. Chavez; James D. Absher; Patricia L. Winter

2008-01-01

Fire events often have a large impact on recreation and tourism, yet these issues had not been addressed from a social science perspective. To address his, the Wildland Recreation and Urban Cultures Research Work Unit (RWU) of the Pacific Southwest Research Station acquired funding through the National Fire Plan within the community assistance topic area. The three...

46 CFR 109.223 - Fire fighting equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...

46 CFR 109.223 - Fire fighting equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...

46 CFR 109.223 - Fire fighting equipment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...

46 CFR 109.223 - Fire fighting equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Fire fighting equipment. 109.223 Section 109.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Tests, Drills, and Inspections § 109.223 Fire fighting equipment. The master or person in charge...

46 CFR 109.223 - Fire fighting equipment.