Calibration of thermoluminescence and film dosemeters for skin doses from high-activity microparticles
The use of EXT-RAD™ extremity TLDs and radiochromic film to measure doses from primarily beta-emitting microparticles is discussed. Specific calibration techniques have been developed, using both Monte Carlo modelling and experiments. Results for a 90Sr/90Y microparticle are presented to illustrate the general techniques and to demonstrate reasonable agreement between the dosimetry methods. (Source: Radiation Protection Dosimetry)
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Eakins, J. S., Hager, L. G., Tanner, R. J. Tags: Paper Source Type: research
A study on the uncertainty for the routine dosimetry service at the lebanese atomic energy commission using harshaw 8814 dosemeters
The personal dosimetry service at the Lebanese Atomic Energy Commission uses Harshaw 8814 cards with LiF:Mg,Ti detectors. The dosemeters are read in a Harshaw 6600 TLD reader. In the process of accreditation for the ISO 17025 standard(1), different influence factors are investigated and the uncertainty has been determined. The Individual Monitoring Service Laboratory—LAEC reads the dosemeters once it receives them from the customer, and new cards are immediately given for the next wearing period. The wearing period is 2 months. The dosemeter results are reported to the customers without background subtraction. Both H...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Rizk, C., Vanhavere, F. Tags: Paper Source Type: research
Comparison of different padc materials and etching conditions for fast neutron dosimetry
Etched-track polyallyl diglycol carbonate (PADC) dosemeters have been in use at the Paul Scherrer Institute since 1998 in neutron dosimetry for individual monitoring. In the last years, the availability of PADC materials from different manufacturers has grown, and different etching conditions were proposed, with the intention to improve the quality and overall performance of PADC in individual neutron monitoring. The goal of the present study was to compare the performance of different PADC materials and to investigate the influence of different etching conditions on sensitivity to fast neutrons and lower detection limit. ...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Assenmacher, F., Boschung, M., Hohmann, E., Mayer, S. Tags: Paper Source Type: research
Generalisation of radiator design techniques for personal neutron dosemeters by unfolding method
A novel technique for designing a radiator suitable for personal neutron dosemeter based on plastic track detector was discussed. A multi-layer structure has been proposed in the previous report, where the thicknesses of plural polyethylene (PE) layers and insensitive ones were determined by iterative calculations of double integral. In order to arrange this procedure and make it more systematic, unfolding calculation has been employed to estimate an ideal radiator containing an arbitrary hydrogen concentration. In the second step, realistic materials replaced it with consideration of minimisation of the layer number and c...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Oda, K., Nakayama, T., Umetani, K., Kajihara, M., Yamauchi, T. Tags: Paper Source Type: research
Stability of the neutron dose determination algorithm for personal neutron dosemeters at different radon gas exposures
Since 2008 the Paul Scherrer Institute (PSI) has been using a microscope-based automatic scanning system for assessing personal neutron doses with a dosemeter based on PADC. This scanning system, known as TASLImage, includes a comprehensive characterisation of tracks. The distributions of several specific track characteristics such as size, shape and optical density are compared with a reference set to discriminate tracks of alpha particles and non-track background. Due to the dosemeter design at PSI, it is anticipated that radon should not significantly contribute to the creation of additional tracks in the PADC detector....
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Mayer, S., Boschung, M., Butterweck, G., Assenmacher, F., Hohmann, E. Tags: Paper Source Type: research
Dosimetric properties of the new tld albedo neutron dosemeter awst-tl-gd 04
A new official albedo dosemeter based on thermoluminescent detectors has been introduced in 2015 by the individual monitoring service of the Helmholtz Zentrum München for monitoring persons who are exposed occupationally against photon and neutron radiation. To enhance the sensitivity for fast neutrons, a new badge with an enlarged albedo window has been developed at TU Dresden. The properties of the new albedo dosemeter are discussed, and the results of official intercomparisons and field calibrations are shown. (Source: Radiation Protection Dosimetry)
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Haninger, T., Henniger, J. Tags: Paper Source Type: research
Edel: enea dosemeter for eye lens
Since the publication of International Commission on Radiological Protection statement in 2011 on tissue reaction, eye lens radiation protection played an important role in exposed personnel dosimetry. For this reason, the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) Individual Monitoring Service decided to study a prototype to fulfil specific requests (e.g. for survey in interventional department and intercomparisons). On the basis of such preliminary investigation, a new eye lens dosemeter was developed. The new dosemeter, named EDEL (ENEA Dosemeter for Eye Lens), was c...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Ferrari, P., Mariotti, F., Campani, L. Tags: Paper Source Type: research
Simplified practical test method for portable dose meters using several sealed radioactive sources
Sealed radioactive sources which have small activity were employed for the determination of response and tests for non-linearity and energy dependence of detector responses. Close source-to-detector geometry (at 0.3 m or less) was employed to practical tests for portable dose meters to accumulate statistically sufficient ionizing currents. Difference between response in the present experimentally studied field and in the reference field complied with ISO 4037 due to non-uniformity of radiation fluence at close geometry was corrected by use of Monte Carlo simulation. As a consequence, corrected results were consistent ...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Mikamoto, T., Yamada, T., Kurosawa, T. Tags: Paper Source Type: research
Comparison methodologies for calibration of hp(10) personal dosemeters using iso 4037 and iso 29661 standards
The calibration of electronic personal dosemeters at the Portuguese ionizing radiation metrology laboratory uses the standard IEC 61526 for calibration methodology. This standard describes the irradiation geometry for testing and indicates that the standard ISO 4037-1, 2, 3 and 4 should be used. The ISO 4037 establishes that the reference point of test is a point in the radiation monitor, known or established, and the calibration phantom should be placed on its back in order to simulate the trunk body. Recently, ISO published another standard, the ISO 29661, that changes the reference point from the radiation monitor ...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Cardoso, J., Santos, L., Carvalhal, G., Oliveira, C. Tags: Paper Source Type: research
Dosimetric quality assurance interpreted for iso 17025 in public health england's personal dosimetry service
Many individual monitoring services (IMSs) have long experience in delivering high-quality dosimetry, and many follow rigorous quality assurance (QA) procedures. Typically, these procedures have been developed through experience and are highly effective in maintaining high-quality dose measurements. However, it is not always clear how the range of QA procedures normally followed by IMSs maps on to the various requirements of ISO 17025. The Personal Dosimetry Service of Public Health England has interpreted its QA procedures both in operating existing services and in developing a new one. (Source: Radiation Protection Dosimetry)
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Gilvin, P. J., Gibbens, N. J., Baker, S. T. Tags: Paper Source Type: research
Characterization of an active dosemeter according to iec 61526:2010
The active personal dosemeter, RaySafe i2, allows the measurement and record of Hp(10) in real time, every second, via wireless technology for real-time display on a portable computer and/or a local network. The system seems particularly attractive for individual monitoring at clinical facilities where high intensity and varying radiation fields may occur, as it enables the user to acknowledge and optimize the dose and dose rate values in real time for each procedure. Prior to its use, the system was characterized at the Metrology Laboratory of Ionizing Radiation of IST-LPSR aiming at the metrological characterization...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Cardoso, J., Santos, J. A. M., Santos, L., Alves, J. G., Oliveira, C. Tags: Paper Source Type: research
Investigation of the extended range rem-counter smartrem-linus in reference and workplace fields expected around high-energy accelerators
Radiation survey instrumentation is adequate for the use around high-energy accelerators if capable to measure the dose arising from neutrons with energies ranging from thermal up to a few gigaelectronvolts. The SmartREM-LINUS is a commercial extended range rem-counter, consisting of a central 3He-proportional counter surrounded by a spherical moderator made of borated polyethylene with an internal shield made of lead. The dose rate indicated by the SmartREM-LINUS was investigated for two different irradiation conditions. The linearity and the angular dependence of the indicated dose rate were investigated using reference ...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Hohmann, E., Trovati, S., Strauch, U., Mayer, S. Tags: Paper Source Type: research
Current status of individual dosimetric monitoring in ukraine
About 50 000 workers are being occupationally exposed to radiation in Ukraine. Individual dosimetric monitoring (IDM) is provided by 77 dosimetry services and laboratories of very different scale with a number of monitored workers ranging from several persons to ~9000. In the present work, the current status of personal dosimetry in Ukraine was studied. The First National Intercomparison (FNI) of the IDM labs was accompanied by a survey of the laboratory operation in terms of coverage, types of dosimetry provided, instrumentation and methodologies used, metrological support, data recording, etc. Totally, 34 laboratories re...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Chumak, V., Deniachenko, N., Makarovska, O., Mihailescu, L.- C., Prykhodko, A., Voloskyi, V., Vanhavere, F. Tags: Paper Source Type: research
Eurados intercomparisons on whole-body dosemeters for photons from 2008 to 2014
Starting in 2008 the European Dosimetry Group (EURADOS) has been performing international intercomparisons on photon whole-body dosemeters for individual monitoring services. These intercomparisons were organised (on a biannual basis) in 2008, 2010, 2012 and 2014, each time with a similar set-up but with small alterations in the subsequent irradiation plans. With an increasing number of participants and participating systems, this intercomparison action has become an important tool for individual monitoring services to test their whole-body dosimetry systems, compare their results with other services or systems and to impr...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Figel, M., Stadtmann, H., Grimbergen, T. W. M., McWhan, A., Romero, A. M. Tags: Paper Source Type: research
Use of a simple thermalised neutron field for quality acceptance of whole body tlds
The individual monitoring service of Public Health England (PHE) uses Harshaw™ whole-body and extremity thermoluminescent dosemeters (TLDs) with high-sensitivity lithium fluoride LiF:Mg,Cu,P, together with Harshaw 8800™ automated readers. The neutron-insensitive, 6Li-depleted variety of TLD material is used by PHE because the service provides separate neutron and photon dosemeters. The neutron dosemeters are not sensitive to photons and vice versa. Since insensitivity to neutrons is a supply requirement for TLDs, there is a need to test every new (annual) consignment for this. Because it is thermal neutrons tha...
Source: Radiation Protection Dosimetry - September 7, 2016 Category: Radiology Authors: Gilvin, P. J., Baker, S. T., Eakins, J. S., Tanner, R. J. Tags: Paper Source Type: research
