Dose calibrators are not usually used to measure the activity of pure beta-emitting radionuclides. In this work, the activity of 32P-sodium phosphate was accurately measured with a Capintec CRC-2 dose calibrator. Using a calibration knob setting of 012 on the 1-mCi range, ...

Commercial reentrant ionization chambers ('dose calibrators') have become the de facto standard instrument for making radioactivity measurements in the radiopharmaceutical industry. Accurate activity measurements, however, depend on the application of the correct calibration factor (dial setting) for the ...

... an air gap, off-axis prescription point and plastic bag containing anesthetic isoflurane gas. The dose rate in ... reduced by addition of the air gap and plastic bag. In conclusion, more accurate dose del...

The objective of radiation therapy is to deliver a lethal dose of radiation to the diseased target while minimizing dose to surrounding healthy tissue. This goal constantly motivates the development of treatment modalities which can deliver dose more conformally. In turn, the advances of modern radiotherapy necessitate new ...

... Title : SIMPLE AND ACCURATE CALIBRATION MODEL FOR HYDROGEN- CONTENT, BETA-PARTICLE BACKSCATTER GAUGES. ...

Calibration Overview Calibration ensures that the data received from the instrument are converted into meaningful and accurate measurements.

... calibration may be sufficient for future re-calibrations. Generally, the static calibration can be done more quickly and more accurately. ...

The irradiation of blood before transfusion into immunosuppressed patients is an increasingly common technique used to prevent graft-versus-host disease. A technical procedure is described for the calibration of blood irradiators, including the determination of absolute dose rate and relative dose distribution over the blood volume. ...

In this work the extent of the linear dose response and the dynamic dose range of N-vinylpyrrolidone-argon based (VIPAR) polymer gels were investigated. VIPAR gels were irradiated using a 6 MV linear accelerator up to 60 Gy and a Nucletron microSelectron 192Ir HDR brachytherapy source to much higher doses to cover a ...

he need is increasing for both high radiation exposures and calibration measurements that provide traceability of such exposures to national standards. The applications of high exposures include: electronic component damage studies, sterilization of medical products and food irradiation. Accurate high exposure measurements are difficult to obtain and ...

The radionuclide 131I has important thyroid-related diagnostic and therapeutic applications. The response of the NPL secondary standard radionuclide calibrator has been measured for commercially available 131I capsules used in these applications. The capsules were assayed in the secondary standard ionization chamber using an appropriate jig. They were then dissolved to enable ...

The Fricke dosimetry is used for accurate measurement of the absorbed dose in water irradiated with x- or gamma rays or high-energy electrons. The method is based on the process of oxidation of ferrous to ferric ions by ionizing radiation and can be used accurately for absorbed dose determination in the range from ...

The use of polymer gel dosimeters in brachytherapy can allow the determination of three-dimensional dose distributions in large volumes and with high spatial resolution if an adequate calibration process is performed. One of the major issues in these experiments is the polymer gel response dependence on dose rate when high ...

treatments fail because of improper calibration and plugged nozzles. Sprayer calibration Proper sprayer calibration is critical to accurate herbicide application. Sprayers that...

- Getting it right Often treatments fail because of improper calibration and plugged nozzles. Sprayer calibration Proper sprayer calibration is critical to accurate herbicide...

The increased utilization of x-ray imaging in image-guided radiotherapy has dramatically improved the radiation treatment and the lives of cancer patients. Daily imaging procedures, such as cone-beam computed tomography (CBCT), for patient setup may significantly increase the dose to the patient's normal tissues. This study investigates the dosimetry from a kilovoltage (kV) ...

The increased utilization of x-ray imaging in image-guided radiotherapy has dramatically improved the radiation treatment and the lives of cancer patients. Daily imaging procedures, such as cone-beam computed tomography (CBCT), for patient setup may significantly increase the dose to the patient's normal tissues. This study investigates the dosimetry from a ...

For over 50 years, electron beams have been an important modality for providing an accurate dose of radiation to superficial cancers and disease and for limiting the dose to underlying normal tissues and structures. This review looks at many of the important contributions of physics and dosimetry to the development and utilization of ...

For over 50 years, electron beams have been an important modality for providing an accurate dose of radiation to superficial cancers and disease and for limiting the dose to underlying normal tissues and structures. This review looks at many of the important contributions of physics and dosimetry to the development and utilization of ...

The accurate determination of personal dose equivalent requires the proper use of appropriate radiological quantities and units, knowledge of the dose equivalent response of the personal dosemeters used and detailed information on the fluence as well as dose equivalent spectra at the workplaces. This information ...

Dosimetry measurements and calibrations have been made at the University of Washington's Fast Neutron Medical Research Facility. The facility is designed to deliver localized neutron doses of a few rads to the testes of volunteer subjects at 2.5 MeV and 14 MeV. Dose measurements were based on the use of tissue equivalent ion ...

The invention is directed to an apparatus for accurately calibrating ergometers so that the work rate produced during exercising on the ergometer can be determined accurately. The apparatus can be used to calibrate any ergometer that utilizes a rotating s...

Values for the dose equivalent are required for radiation protection purposes, but determination of such values can be quite difficult for high energy radiations. The accurate determination of personal dose equivalents in accelerator radiation fields requires the propel use of appropriate radiological quantities and units, knowledge of ...

Radiochromic Dye Dosimeters (Gafchromic DM-100) were used to measure the absorbed doses in liquid samples exposed to a {sup 137}Cs gamma-ray source. The initial calibration of commercially available radiochromic film was performed using a {sup 60}Co gamma-ray source. When exposed to gamma-ray doses of 0.5 to 200 kGy, a color change ...

In this work, personal thermoluminescence dosimeter (TLD) cards type of GN-6770 (holder type 8806) from Harshaw were used for personal neutron dosimetry. The response of the dosimeters has been determined in terms of the personal absorbed dose and personal dose equivalent for different neutron energy components, based on the recommendations of ICRP-60 and ...

Ferrous-cupric sulfate dosimetry is used for accurate measurement of the absorbed dose in water irradiated with x- or gamma-rays or high-energy electrons. It is based on the process of oxidation of ferrous to ferric ions by ionizing radiation. The method is most accurate for absorbed doses in the range from 2 x ...

Both polymer gels and PRESAGE radiochromic solid dosimeter, in conjunction with optical CT scanning system, have been employed to measure 3-D dose distribution. The 3-D dose maps obtained from these systems can provide a useful tool for dose verification on complex treatments such as IMRT, radiosurgery, and RapidArc. These complex ...

Estimating the effective dose E with dosemeters calibrated in terms of the personal dose equivalent H(p)(10), one should take into account that the ratio of these two values, i.e. the conversion coefficient C(k), depends essentially on angular and energy parameters of the incident radiation field and is not always close to unity. ...

The increasing use of electrical stimulation of the brain for relief of pain, spasticity and epilepsy has introduced unfamiliar techniques into clinical neurological and neurosurgical practice. In view of the evidence that excessive levels of stimulation can damage brain tissue, it is of great importance to monitor the dose of stimulation. A review of recent clinical papers ...

The complexity of radiotherapy techniques requires an accurate verification of the dose delivered to the patient during treatment. Recently, the present authors have developed an in patient dose reconstruction method with X-ray beams for 3D conformal radiotherapy. The procedure is based on correlation functions defined by the ratios of ...

Film dosimetry is an attractive tool for dose distribution verification in intensity modulated radiotherapy (IMRT). A critical aspect of radiochromic film dosimetry is the scanner used for the readout of the film: the output needs to be calibrated in dose response and corrected for pixel value and spatial dependent nonuniformity caused ...

The radiation-induced ultraviolet absorption in transparent plastics has been investigated in detail and found to be a convenient, rapid, inexpensive, and accurate method of measuring radiation doses between 10/sup 5/ and 2 x 10/sup 8/ rads. In methyl methacrylate (Perspex) the change in optical density at 2920 A is a linear function of the ...

... Title : Alanine Dosimetry Accurately Determines Radiation Dose in Nonhuman Primates. Descriptive Note : Special publication. ...

A recently developed stochastic resist model, implemented in the PROLITH X3.1 lithography simulation tool, is fitted to experimental data for a commercially available immersion ArF photoresist, EPIC 2013 (Dow Electronic Materials). Calibration is performed using the mean CD and LWR values through focus and dose for three line/space features of varying ...

BackgroundIn nuclear medicine, liquid radiopharmaceuticals for diagnostic or therapeutic purposes are administered to patients by using various types of syringes with different volumes. The activity of each "dose" must be carefully measured and documented prior to administration using an activity calibrator.MethodsCalibrator response is a function of the ...

It is often necessary to estimate the dose of radiation to a fetus from a series of CT scans. To assist in making this process easier and more accurate, we measured fetal doses in an adult anthropomorphic phantom for four CT scanners: Picker 1200, Siemens DRH, GE 9800, and GE 8800. Measurements were made at four kilovoltages (100, 120, ...

A commercial dual photon energy, computer-controlled linear accelerator has a complex collimation and beam delivery system. For accurate dose delivery, six separate motorized elements must be properly positioned for a given beam selection. Experimentally instituted misalignments of the primary electron scattering foils, the primary collimator, the ...

Instrument calibration enables accurate characterization of performance to enable collection and extraction of precise scientific measurements. The calibration ...

... and accurate method for calibrating an instrument for measuring the reflection coefficient and complex permittivity of unknown dielectric materials in ...

... instrument calibrations are usually obtained by usag a very accurate laboratory barometer. The altitude scales on these barometers are based on ...

... AND DEPTH (CTD) PROFILER ... To ensure accurate sound velocity profiles, it is important that CTD sensors are properly calibrated. Techniques ...

... 577 CALIBRATING GPS WITH TWSTFT FOR ACCURATE TIME TRANSFER ... 83% of UTC time links are obtained via GPS observations. ...

This interlaboratory comparison validates the dicentric chromosome assay for assessing radiation dose in mass casualty accidents and identifies the advantages and limitations of an international biodosimetry network. The assay's validity and accuracy were determined among five laboratories following the International Organization for Standardization guidelines. Blood samples ...

Accurate calibration of line-of-sight delay fluctuations in the Earth's atmosphere ... formance of the calibration system of water-vapor-induced path delay. ...

... Linear estimation is a viable method for analyzing mixed pixels under the simplified assumption of accurate reflectance calibration, accurate ...

The study on thyroid volume consists of measuring the scatter component from the thvroid gland by differential scanning after the subject has swallowed a dose of radioactive iodine (I-131), and then to find out the gland volume from the calibration curve, in contrast to other available methods, namely palpation and scintiscanning measurement in two ...

Accurate estimate of absorbed dose to target tumors and normal tissues in the body is an important requirement for establishing fundamental dose-response relationships for radioimmunotherapy. Two major obstacles have been the difficulty in obtaining an accurate patient-specific 3-D activity map in-vivo and ...

A primary limitation of current x-ray CT polymer gel dosimetry is the low contrast, and hence poor dose resolution, of dose images produced by the system. The low contrast is largely due to the low-dose sensitivity of current formulations of polymer gel for x-ray CT imaging. This study reports on the investigation of new dosimeter ...

A primary limitation of current x-ray CT polymer gel dosimetry is the low contrast, and hence poor dose resolution, of dose images produced by the system. The low contrast is largely due to the low-dose sensitivity of current formulations of polymer gel for x-ray CT imaging. This study reports on the investigation of new dosimeter ...

Proton radiotherapy centers that currently use passively scattered proton beams do field specific calibrations for a non-negligible fraction of treatment fields, which is time and resource consuming. Our improved understanding of the passive scattering mode of the IBA universal nozzle, especially of the current modulation function, allowed us to re-commission our treatment ...

The accurate measurement of ion beam dose is a key point of quantitative analytical methods like PIGE, PIXE or RBS. To solve this problem for our Oxford-type scanning nuclear microprobe (SNM), a small-sized compact beam chopper has been developed. Ion beam dose is derived from the observed RBS yield from the surface of a wing after ...

We report here a rapid method of electron paramagnetic resonance (EPR) dosimetry of dental enamel which will allow screening of whole deciduous teeth of children following a nuclear accident. The technique requires virtually no sample preparation and is capable of measuring doses of less than 100 mGy. Teeth may be scanned for threshold dose levels without ...

To improve the methodology for assessing neutron dose at Union Electric's Callaway Nuclear Power Plant, an intercomparison of neutron detectors and dosimeters was performed. Seven different neutron detectors and dosimeters were tested in four different neutron fields utilizing facilities at the Missouri University Research Reactor and at the Southwest Radiation ...

To improve the methodology for assessing neutron dose at Union Electric's Callaway Nuclear Power Plant, an intercomparison of neutron detectors and dosimeters was performed. Seven different neutron detectors and dosimeters were tested in four different neutron fields utilizing facilities at the Missouri University Research Reactor and at the Southwest Radiation ...

This report is part of a series prepared under the auspices of Scientific Committee 46, Operational Radiation Safety. It provides guidance on the calibration of survey instruments for the assessment of ionizing radiation fields and radioactive surface contamination. One essential element in the effective use of survey instruments is the knowledge that instruments are properly ...

Table of Contents: Abstract; Introduction; Electronics; Troubleshooting and Repair; Electronic Setup; Dose Response Calibration and References.

. Calibration An external dose calibrator (Capintec CRC-15R) is used as the gold standard for comparison

The development of high linear energy transfer (LET), passive radiation dosimetry and spectrometry is needed for the purpose of accurate determination of equivalent doses and assessment of health risks to astronauts on long duration missions. Progress in the following research areas is summerized: intercomparisons of cosmic ray equivalent ...

The high dose standards and dissemination system of electron beams are being established at NIM. The graphite and/ or water calorimeters and liquid chemical dosimeter are to be accepted as standards. The transfer dosimeter selected are alanine/ESR dosimeter and radiochromic film (FWT - 60). Several kinds of radiochromic films, undyed cellulose triacetate, polyethylene and blue ...

In the absence of a predictor of beam output in proton therapy using a broad beam, the beam output is obtained for individual treatments by calibrating the beam monitors. The calibration is carried out under conditions similar to the treatment conditions but with a phantom instead of the patient. However, the dose in the phantom a ...

A multi-layer ionization chamber (MLIC) which consists of a stack of parallel plate-type ionization chambers in which the parallel configuration is in the depth direction was developed at the National Institute of Radiological Science (NIRS) and has been used as a field dosimeter for MU calibration since 2002. Although the MLIC can measure depth dose ...

Various forms of Gafchromic films that are increasingly used for dosimetry in radiotherapy offer the prospect of reproducible and accurate high-resolution two-dimensional dose measurements, but there are many unresolved issues regarding the optimal choice of densitometric procedure used for the film's optical density (OD) readout. There are conflicting ...

Autonomous robot task execution requires that the end effector of the robot be positioned accurately

to interface with any higher level langauge. The card has several ..... calibration body was used as an accurate reference in loading the balance. ...

A method for measuring a film sensitometric curve using a single sheet of film exposed with a two field step-and-shoot MLC treatment was developed and tested with Kodak XV2 and EDR2 films. With this technique a film sensitometric curve can be completed in only 10 minutes, making it practical to generate new film calibrations daily. This method is applicable to film ...

The intensity of /sup 137/Cs, /sup 192/Ir, and /sup 226/Ra brachytherapy sources is currently specified in terms of exposure rate as measured in a scatter-free geometry utilizing a long source to detector distance. For reasons of convenience, such sources are routinely calibrated using some type of re-entrant ionization chamber such as the dose ...

The intensity of ('137)Cs, ('192)Ir, and ('226)Ra brachytherapy sources is currently specified in terms of exposure rate as measured in a scatter-free geometry utilizing a long source to detector distance. For reasons of convenience, such sources are routinely calibrated using some type of re-entrant ionization chamber such as the dose ...

In this paper, we discuss the performance of EUV resist models in terms of predictive accuracy, and we assess the readiness of the corresponding model calibration methodology. The study is done on an extensive OPC data set collected at IMEC for the ShinEtsu resist SEVR-59 on the ASML EUV Alpha Demo Tool (ADT), with the data set including more than thousand CD values. We ...

Freshly prepared radiochromic ferrous xylenol-orange (FX) gels optically scanned with a light source exhibit a threshold dose response that is thermally and wavelength dependent. Correction for this threshold dose leads to accurate dose calibration and better reproducibility in multiple ...

The use of magnetic resonance imaging as a readout method for polymer gel dosimetry commonly involves long imaging sessions, particularly when high spatial resolution is required in all three dimensions, for the investigation of dose distributions with steep dose gradients and stringent dose delivery specifications. In this work, a ...

Estimates of biological effects associated with exposure to external radiation fields are generally based on the measured response of passive personnel dosimetry systems to the incident radiation. The increasing number of persons occupationally exposed to mixed neutron and gamma fields and recent questions concerning the relative biological hazards of different types of radiation have emphasized ...

Before a CAM is put into service, it must be calibrated. The flow meter and detector must be calibrated with an external flow meter to provide accurate flow data, and the detector must be calibrated to produce accurate DPM data. Both flow and DPM data ent...

Accurate calibration of accelerometers requires that accurate measurement techniques be developed and maintained. Calibrations of vibration exciters and pickups are performed by comparison with the response characteristics of NBS standard accelerometers o...

A pendulum device using a force transducer is found to be an accurate shock calibrator for accelerometers, preliminary results indicate that vibration calibration data are valid for shock outputs of Endevco Models 2214, 2224, 2224B and 2225. (auth)

This document describes the Hanford External Dosimetry Program as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy (DOE) and its Hanford contractors. Program services include administrating the Hanford personnel dosimeter processing program and ensuring that the related dosimeter data accurately reflect occupational ...

Accurate calculation of absorbed dose to target tumors and normal tissues in the body is an important requirement for establishing fundamental dose-response relationships for radioimmunotherapy. Two major obstacles have been the difficulty in obtaining an accurate patient-specific 3-D activity map in-vivo and ...

Portable neutron rem meters are calibrated at Los Alamos using a Pu- 239/Be neutron source located inside a well. The Los Alamos Neutron Well is calibrated using an Eberline NRD detector that has been calibrated to the source free-in-air. Because the NRD detector's inherent energy response does not closely follow the true ...

A monitoring instrument based on a high-pressure ionization chamber has been developed that measures average dose rates as low as 0.1 mR/h and responds linearly to short pulses at dose rates up to 1.2 x 10/sup 10/ R/h. Its sensitivity can be remotely changed by a factor of 10/sup 4/, to enable accurate measurement of both background ...

Accurate measurements of neutron doses in the containment of a commercial nuclear power plant have been a concern in the last several years. If neutron dosimeters are used to assess exposures in a spectral environment substantially different from that in which they were calibrated, the dose equivalent ...

The design, construction and calibration of a convenient irradiator is described that provides controlled exposure to a uniform external source of well-characterized alpha particles at a dose-rate of 0.99 cGy min-1. The use of a precis- ion photographic shutter allows the accurate delivery of doses as low as 0.01 ...

Manual tank calibrations often have variabilities of both a random and systematic nature that often affect the quality of the data collected for determining accurate calibration equations. When performing the calibration run, data omissions and transcript...

A Faxitron sealed x-ray cabinet, operated at 100 kV, was modified to irradiate monkey testicles, to a uniform, accurately calibrated dose, for work aimed at investigating spermatogenesis in children undergoing radiotherapy. An aluminium filter was added to increase the beam quality and a lead collimating system manufactured to reduce ...

Electronic portal imaging devices (EPIDs) are not only applied for patient setup verification and detection of organ motion but are also increasingly used for dosimetric verification. The aim of our work is to obtain accurate dose distributions from a commercially available amorphous silicon (a-Si) EPID for transit dosimetry applications. For that purpose, ...

Because for IMRT treatments the required accuracy on leaf positioning is high, conventional calibration methods may not be appropriate. The aim of this study was to develop the tools for an accurate MLC calibration valid for conventional and IMRT treatments and to investigate the stability of the MLC. A strip test consisting of nine ...

Because for IMRT treatments the required accuracy on leaf positioning is high, conventional calibration methods may not be appropriate. The aim of this study was to develop the tools for an accurate MLC calibration valid for conventional and IMRT treatments and to investigate the stability of the MLC. A strip test consisting of nine ...

Purpose: At University of California San Francisco, daily or weekly three-dimensional images of patients in treatment position are acquired for image-guided radiation therapy. These images can be used for calculating the actual dose delivered to the patient during treatment. In this article, we present the process of performing dose recalculation on ...

There is a lack of standardized methodology to perform dose calculations for targeted radionuclide therapy and at present no method exists to objectively evaluate the various approaches employed. The aim of the work described here was to investigate the practicality and accuracy of calibrating polymer gel dosimeters such that dose ...

... The five types of ratemeters chosen for project ... COUNTERS, CALIBRATION, SPECIFICATIONS, ERRORS, DETECTORS, DOSE RATE, GAMMA ...

Final comparisons are made between measured and calculated radiation doses around the holes in which the spent fuel was emplaced in the Spent Fuel Test - Climax. Neutron doses were found to be negligible compared with gamma doses. Good agreement was found between the doses predicted by Monte Carlo calculations and ...

Purpose: Volumetric modulated arc therapy (VMAT) involves the simultaneous use of dynamic multileaf collimator (DMLC) techniques and gantry arcing; appropriate quality assurance is therefore required. This article describes the development and implementation of procedures for commissioning VMAT on a commercial linear accelerator (Elekta PreciseBeam VMAT with MLCi and Beam Modulator heads). ...

Calibration of the flash X-ray dose was done in situ with CaF2 total luminescent dosimetry with traceability. ? Threshold dose rates were established for ...

The present invention relates to a device for determining radiation dose and, more particularly, to a standard dose measuring device against which other types of dosimeters may be calibrated.

In this study, we use the quadratic calibration method (QCM), in which an EPID image is converted into a matrix of equivalent path lengths (EPLs) and, therefore, exit doses, so as to model doses in conformal and enhanced dynamic wedge (EDW) fields. The QCM involves acquiring series of EPID images at a reference field size for different ...

+ Proper Tank Mix = Accurate Calibration #12;Examples of calibration & how much to put in the tank BroadcastSprayer Calibration Mike Marshall, Ph.D., Extension Weed Specialist General Information Accurate per acre to fractions of one ounce per acre. Sprayer calibration, ...

Californium-252 is used in a variety of industrial applications to deliver neutron dose. The design of the delivery system, i.e., the system that places the {sup 252}Cf source next to the item being exposed, is a crucial part of a successful irradiator system. This paper reviews different types of delivery systems and discusses the benefits and limitations of each type of ...

A portable spectrometer prototype is built to study wavelength calibration for flat-field grating spectrometers. An accurate calibration method called parameter fitting is presented. Both optical and structural parameters of the spectrometer are included in the wavelength calibration model, which ...

Uncertainties in estimating the potential health impact of a given radiation exposure include instrument measurement error in determining exposure and difficulty in relating this exposure to an effective dose value. Instrument error can be due to design or manufacturing deficiencies, limitations of the sensing element used, and calibration and maintenance ...

A charged particle dosimeter (the Burst Detector Dosimeter or BDD) was designed and fabricated and will be flown on certain of the Global Positioning Satellite (GPS) series of spacecraft. The BDD will monitor the dose received by the GPS spacecraft from the fluxes of electrons and protons in the Earth's radiation belt. The BDD uses absorbers in front of silicon ...

The latest involvement of the Brachytherapy research group of the medical physics program at Hampton University is in the development of a scintillating fiber based detector for the breast cancer specific Mammosite (balloon device) from Cytyc Inc. Recent data were acquired at a local hospital to evaluate the possibility of measuring the dose distribution during breast ...

The latest involvement of the Brachytherapy research group of the medical physics program at Hampton University is in the development of a scintillator fiber based detector for the breast cancer specific Mammosite (balloon device) from Cytyc Inc. Recent data were acquired at a local hospital to evaluate the possibility of measuring the dose distribution during breast ...

... to provide accurate spectroradiometric calibrations in the optical, mid-wave, and longwave infrared spectral regions as well as the near-IR. ...

Jun 19, 2006 ... X-ray Astronomy needs in-flight calibration sources - astronomical ... Since there are no accurate measurements of line intensities yet, ...

This memorandum is a synopsis of the description and operation of the equipment used and the events accuring during the calibration of gauges on the vacuum station over the range of 0.0001 to 650 torr.

This memorandum is a synopsis of the description and operation of the equipment used and the events accuring during the calibration of gauges on the vacuum station over the range of 0.0001 to 650 torr.

... Abstract : A rapid and highly accurate method of calibrating gamma radiation sources such as cesium-137 and cobalt-60 emitters has been devised ...

The report contains a documented computer program for the calibration of comparators used for analytical photogrammetry. The computerized procedure is based on the measurement of 25 grid points whose coordinates are accurately known. The scale errors of t...

Vicarious calibration of ocean color satellites involves the use of accurate surface measurements of

...statement of certification of accurate calibration is on file at the premises; (4) If a tank or its means of measuring is changed...location or position subsequent to original calibration, the tank may not be used until...

... need for accurate radiation dose measurements ... RADIATION MEASURING INSTRUMENTS, *RADIATION DOSAGE, ELECTRONICS, EQUATORIAL ...

... need for accurate radiation dose measurements. ... MEASURING INSTRUMENTS, *DOSIMETERS, *RADIATION DOSAGE, *SCIENTIFIC SATELLITES ...

... the need for accurate radiation dose measurements ... Descriptors : *DOSIMETERS, *RADIATION DOSAGE, *SCIENTIFIC SATELLITES, *RADIATION ...

... to fulfill the need for accurate radiation dose measurements. ... RADIATION, SPACE ENVIRONMENTS, RADIATION DOSAGE, PARTICLE FLUX ...

In the present reporting period we have met with the Pioneer Venus PI to collaborate on the recalibration of the UV spectrometer of Pioneer Venus. The associated data reduction and analysis activities have been completed. The sensitivity of the UV spectrometer has been steadily declining since orbit insertion of Pioneer Venus in 1978 due to aging of the detector tubes. The sensitivity decline is a ...

An experimental irradiation setup was designed to deliver a conformal field of thoracic irradiation to mice. The objective is to provide accurate dosimetric evaluation for the experimental setup, which involves a pie cage device holding up to 10 mice with concentric Cerrobend� shields to collimate the beam. The setup uses 250 kVp X rays, and it also involves an air gap, ...

Radiation therapy accelerators require highly accurate dose deposition and the output must be monitored frequently and regularly. Ionization chambers are the primary tool for this control, but their size, their high voltage needed, and the correction needed for electrons make them unsuitable for use during patient treatment. We have developed a small ...

To protect public health, all deer and feral hogs harvested at the Savannah River Site (SRS) during controlled hunts are monitored for Cs-137. A new monitoring program has been developed by the Environmental Monitoring Section (EMS). To provide increased confidence in dose data and compliance with regulations, many changes have been made to the deer and hog monitoring program. ...

To protect public health, all deer and feral hogs harvested at the Savannah River Site (SRS) during controlled hunts are monitored for Cs-137. A new monitoring program has been developed by the Environmental Monitoring Section (EMS). To provide increased confidence in dose data and compliance with regulations, many changes have been made to the deer and hog monitoring program. ...

The positron emitter 18F continues to be one of the most important imaging radionuclides in diagnostic nuclear medicine. Assays of radiopharmaceuticals containing this nuclide are often performed in the clinic using commercial reentrant ionization chambers, or "dose calibrators". Meaningful quantitative clinical studies require ...

Because some workers have a high potential for significant neutron exposure, the Savannah River Plant (SRP) contracted with Pacific Northwest Laboratory (PNL) to verify the accuracy of neutron dosimetry at the plant. Energy spectrum and neutron dose measurements were made at the SRP calibrations laboratory and at several other locations. The energy spectra ...

It is often necessary to estimate the dose of radiation to a fetus from a series of CT scans. To assist in making this process easier and more accurate, we measured fetal doses in an adult anthropomorphic phantom for four CT scanners: Picker 1200, Siemens DRH, GE 9800, and GE 8800. Measurements were made at four kilovoltages (100, 120, ...

The Canadian high-energy neutron spectrometry system CHENSS was constructed for the Canadian Space Agency CSA to measure accurately the neutron spectrum in low-Earth orbit A large specially formulated viscoelastic scintillator uses proton recoil and good pulse-shape discrimination to measure from a few MeV to about 100 MeV With delays in the NASA flight schedule for the ...

Calibration factors for several makes (Capintec, AtomLab, and PTW) and models of commercially available re-entrant ionization chambers ("dose calibrators") were determined for solutions of 90Y using 10 ml plastic syringes that are used in the administration of the recently approved radioimmunotherapy drug Zevalin. Effects of filling ...

Gafchromic� XR-R films are a useful tool to evaluate entrance skin dose in interventional radiology. Another dosimetric quantity of interest in diagnostic and interventional radiology is the dose area product (DAP). In this study, a method to evaluate DAP using Gafchromic� XR-R films and a flat-bed scanner was developed and tested. Film samples were ...

A new method of generating analog test signals with accurate signal-to-noise .... may have, if desired, the same frequency response, in which ...

... accurate and replicable from a competent laboratory: pH value � chemistry grade pH paper accurate to ±0.05 or calibrated equipment; ...

A measuring assembly which forms together with a calorimeter, a stable and accurate means to measure local absorbed dose in high energy photon or electron beams, is described. The assembly contains AC bridges with phase sensitive detectors which provide good noise rejection and high sensitivity for the measurement of very small temperature changes sensed ...

External audit of the absorbed dose determination from radiotherapy machines is performed using Lithium fluoride (LiF) TLD-100. Optimal parameters needed to obtain highly accurate dosage from LiF powder was investigated, including the setup of the Harshaw 4000 reader. A linear correspondence between the thermoluminescent signal and the mass of the powder ...

Many of the facilities licensed by the Atomic Energy Control Board (AECB) produce neutron radiation fields in occupationally accessible areas. The accurate measurement of these fields and the reliability of personal neutron monitoring systems with necessary energy response, sensitivity and accuracy are of concern to the AECB. This study determined which type of neutron ...

Calibration spots of optically-characterized material placed in the field of view of a spectroscopic system allow calibration of the spectroscopic system. Response from the calibration spots is measured and used to calibrate for varying spectroscopic system operating parameters. The accurate ...

Calibration spots of optically-characterized material placed in the field of view of a spectroscopic system allow calibration of the spectroscopic system. Response from the calibration spots is measured and used to calibrate for varying spectroscopic system operating parameters. The accurate ...

This study was designed to observe the feasibility of the use by NRC licensees of the tissue equivalent proportional counter (TEPC) system as a neutron monitoring instrument. Laboratory tissue equivalent proportional counters were irradiated using /sup 252/Cf sources at NBS and PNL and were irradiated inside containment of four operating nuclear power plants (two boiling water reactors and two ...

To provide for accurate dosimetry in a 137Cs irradiator, the following were investigated: (1) correct mapping of the irradiator cavity's dose distribution, (2) rotated versus stationary dose rate measurements, (3) exposure-to-dose calibration selection for exposure time calculation, and (4) ...

The present paper addresses reference dose measurements using thimble ionization chambers for quality assurance in IMRT fields. In these radiation fields, detector fluence perturbation effects invalidate the application of open-field dosimetry protocol data for the derivation of absorbed dose to water from ionization chamber measurements. We define a ...

Blood pressure and body temperature measurements need to be accurate for correct diagnosis and monitoring. Instruments based on new technologies may not give accurate measurements. This article considers the implications for healthcare professionals. The need for instruments to be traceably calibrated to national standards is ...

... doses. ... were reeolved to provide continuous dose-rate data with respect to accurate time. 29 ... radiation and an estimate of its contribution to the total ...

In developing a policy that will require licensees to calibrate their radiation dose measuring devices and trace such calibrations to approved reference standards, the AECB has consulted recognized experts. This document presents the experts' reports and ...

We present accurately calibrated submillimeter atmospheric transmission spectra obtained with an FTS

The calibration and operational performance of an FTIR-based airborne high-resolution interferometer

The instruments use calibration targets, including a sundial, to determine accurate colors, brightnesses, and other information collected by the instruments ...

... Abstract : The free-burning DC electric arc and plasma jet operating in argon at atmospheric pressure were accurately calibrated and compared ...

... paper discusses issues related to the use of hyperspectral sensors. ... military targets as well as the accurate calibration and atmospheric correction. ...

The equipment used for wind velocity measurement in the KNMI wind tunnel was calibrated in view of displacement of the wind tunnel. Four cup anemometers and three trivanes were used for this investigation. These instruments were calibrated accurately in t...

The methods used to calibrate the pointing direction of the Mars 71 spacecraft scan platform are described. Accurate calibration was required to meet the pointing accuracy requirements of the scientific instruments mounted on the platform. A detailed grou...

Describes the improvements effected during the last ten years, which have made the facility more accurate and versatile. Includes the results of an interorganizational cross-calibration program for reversing thermometers. (Author)

Accurate determinations of fusion neutron yields on the TFTR require that the neutron detectors be absolutely calibrated in-situ, using neutron sources of known strengths. For such calibrations, numerical simulations of neutron transport can be powerful t...

It is well known that, to accurately retrieve the spectrum of the water-leaving radiance and derive the ocean color products from satellite sensors, a vicarious calibration procedure, which performs sensor in-orbit calibration for a whole system (the sens...

This report documents relevant considerations and results from volume calibration studies on eight process tanks in the Integrated Equipment Test (IET) facility. Accurate calibration data for these tanks are an important part of the data base required for...

The feasibility of global calibration of terrestrial reference cells is discussed. A simple, accurate 'secondary' calibration technique based on ratios of test to reference cell currents measured in natural sunlight is described. Different techniques for ...

To permit accurate evaluation of previous airborne measurements, the AFCRL first-generation circular variable filter (CVF) spectrometer was calibrated in the AEROSPACE Research Chamber (7V). Testing consisted of calibration and linearity checks, angular r...

Using current, improved commercial equipment, the authors reexamined the calibration procedure of the dual-probe gamma soil densitometer, using exact density standards. When each instrument is individually calibrated, the procedure, as originally designed, gives consistent and accurate results.

The procedure describes the calibration of the Radio Frequency Laboratories, Inc. Model 33 AC-DC- Meter Calibrator. The test instrument is a self contained unit providing accurate av, dv, ac, or dc outputs. (Author)

...must measure the spirits by using: (1) A tank or bulk conveyance for which a calibration chart is provided, with the calibration charts...as accurate by persons qualified to calibrate tanks or bulk conveyances; or (2) An...

TLD's replaced film badges in the early 1970's for all dose equivalent monitoring, both neutron and photon, and for all locations at SLAC. The photon TLD's, composed of Li-7 loaded teflon discs, are calibrated using conventional gamma-ray sources; i.e., Co-60, Cs-137, etc. For these TLD's a nominal value of 1 nC/mrem is ...

The authors have studied the feasibility of using three new high-sensitivity radiochromic devices in measuring the doses to peripheral points outside the primary megavoltage photon beams. The three devices were GAFCHROMIC� EBT film, prototype Low Dose (LD) Film, and prototype LD Card. The authors performed point dosimetry using these three devices in ...

It has been a challenge to perform accurate 2D or 3D dosimetry in the surface region with steep dose gradient for megavoltage photon beams. We developed a dosimetry method in the superficial buildup region for the 6 and 15 MV photon beams using a radiochromic EBT film stack. Eight radiochromic EBT film strips (3 x 20 x 0.024 cm3) stacked together formed a ...

In the United States, the Department of Energy has established a program to improve neutron dosimetry at facilities where a significant number of workers are exposed to fast neutrons from handling isotopic neutron sources. One facet of this program is the development of small, lightweight personnel monitors to determine dose equivalent as the workers are exposed. These ...

Strontium-90 (beta-emitting) applicators for the treatment of pterygia carry the potential for significant (possibly cataractogenic) lens doses previously calculated with imprecise or inaccurate assumptions. We sought to apply modern dosimetry techniques to this problem using the Monte Carlo computer code MCNP version 4.A to model the human eye irradiated with a commonly ...

Treatment planning in proton therapy requires the calculation of absorbed dose distributions on beam shaping components and the patient anatomy. Analytical pencil-beam dose algorithms commonly used are not always accurate enough. The Monte Carlo approach is more accurate but extremely computationally intensive. The ...

Despite its advantages, the polymer gel-magnetic resonance imaging (MRI) method has not, as yet, been successfully employed in dosimetry of low energy/low dose rate photon-emitting brachytherapy sources such as 125I or 103Pd interstitial seeds. In the present work, two commercially available 125I seed sources, each of approximately 0.5 U, were positioned at two different ...

Despite its advantages, the polymer gel-magnetic resonance imaging (MRI) method has not, as yet, been successfully employed in dosimetry of low energy/low dose rate photon-emitting brachytherapy sources such as 125I or 103Pd interstitial seeds. In the present work, two commercially available 125I seed sources, each of approximately 0.5 U, were positioned at two different ...

Neutron dosimetry has been extensively studied at Hanford since the mid-1940s. At the present time, Hanford contractors use thermoluminescent dosimeter (TLD)-albedo dosimeters to record the neutron dose equivalent received by workers. The energy dependence of the TLD-albedo dosimeter has been recognized and documented since introduced at Hanford in 1964 and numerous studies ...

Neutron dosimetry has been extensively studied at Hanford since the mid-1940s. At the present time, Hanford contractors use thermoluminescent dosimeter (TLD)-albedo dosimeters to record the neutron dose equivalent received by workers. The energy dependence of the TLD-albedo dosimeter has been recognized and documented since introduced at Hanford in 1964 and numerous studies ...

Most radiation safety guidelines in the nuclear industry are based on the data concerning the survivors of the nuclear explosions at Hiroshima and Nagasaki. Crucial to determining these guidelines is the radiation from the explosions. We have measured gamma-ray pulse-height distributions from an accurate replica of the Little Boy device used at Hiroshima, operated at low power ...

Dosimetric verification of delivery for intensity-modulated radiotherapy (IMRT) treatment plans is critical to ensure accurate and safe patient treatments. Commonly, a point dose measurement using a calibrated ion chamber as well as a planar dose measurement using film was traditionally implemented for dosimetric ...

Evaluation of the intracellular distribution of radionuclides used for targeted radiotherapy (tRT) is essential for accurate dosimetry. Therefore, a direct and quantitative method for subcellular micro-autoradiography using radiation sensitive polymers (PMMA, UV1116 and AZ40XT) was developed. The electron exposure dose in radio-labelled cells due to Auger ...

Gafchromic EBT (EBT) films are becoming increasingly popular due to their advantageous properties. When flatbed colour scanners are used for film dosimetry, a good quality control of the scanning device is a crucial step for accurate results. The proposal of this work was to fully assess the performance of the scanner Epson Expression 10000XL in order to quantify all ...

Gafchromic EBT (EBT) films are becoming increasingly popular due to their advantageous properties. When flatbed colour scanners are used for film dosimetry, a good quality control of the scanning device is a crucial step for accurate results. The proposal of this work was to fully assess the performance of the scanner Epson Expression 10000XL in order to quantify all ...

Purpose: To extend the Radiological Physics Centre (RPC) intensity-modulated radiation therapy dose verification protocol to three dimensions using optical computed tomography (CT) scans of ferrous xylenol-orange (FX) gels. Methods and Materials: The dosimetry insert in the RPC head-and-neck phantom was replaced with an FX cylindrical gel dosimeter. Two gels were ...

In this research work, a semi-automatic densitometry system has been developed for large-scale monitoring services by use of film badge dosemeters. The system consists of a charge-coupled device (CCD)-based scanner that can scan optical densities (ODs) up to 4.2, a computer vision algorithm to improve the quality of digitised films and an analyser program to calculate the necessary information, ...

BANG-gel dosimetry offers the potential for measuring the dose delivered by a radiotherapy treatment technique, in three dimensions, with high spatial resolution and good accuracy. The ability to measure comprehensively a 3D dose distribution is a major advantage of the gel dosimeter over conventional planar and point-based dosimeter devices, particularly ...

Dose Calibrator (Capintec, Ramsey, NJ, USA) to calculate the percent injected dose per gram of tissue

... Dosimeter, Electron dose, Proton dose, Space ... Nuclear stars, Space radiation dosimeter, CRR Spacecraft. ... PARTICLE FLUX, PROTONS, TEST AND ...

... from protons (high energy loss), the flux of electrons, the flux of protons, and the rate ... Keywords: Dosimeter; Electron dose; Proton dose; Space ...

... loss), the flux of electrons, the flux of protons, and the ... Originator-supplied keywords include: Dosimeter; Electron dose; Proton dose; Space ...

... dosimeters for X rays in the 1�50 MeV range be calibrated in terms of absorbed dose to ... ...

The data obtained from these tests determine the dose rate of the two cobalt sources in SRTC. This testing used chemical dosimetry to measure the dose rate of a radioactive source.