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The assessment of exposure to cosmic radiation on board aircraft is one of the preoccupations of organizations responsible for radiation protection. The cosmic radiation particle flux increases with altitude and latitude and depends on the solar activity. The radiation exposure has been estimated on several airlines using transatlantic, Siberian and transequatorial routes on board subsonic and supersonic aircraft, to illustrate the effect of these parameters: Measurements have been obtained with a tissue equivalent proportional counter using the microdosimetric technique. Data have been collected at maximum solar activity in 1991–1992 and at minimum in 1996–1998. The lowest mean dose rate measured was 3 μSv/h during a Paris-Buenos Aires flight in 1991; the highest was 6.6 μSv/h during a Paris-Tokyo flight using a Siberian route and 9.7 μ Sv/h on Concorde in 1996–1997. The mean quality factor is around 1.8. The corresponding annual effective dose, based on 700 hours of flight for subsonic aircraft and 300 hours for Concorde, can be-estimated between 2 rnSv for least-exposed routes and 5 mSv for more exposed routes. [Copyright &y& Elsevier]

Measurements of the radiation environment inside the Mir space station were performed with a tissue equivalent proportional counter (TEPC) during the Antares mission in 1992, and over a long period following it. Interesting results concerning radiation measurements show (a) the South Atlantic Anomaly crossing, (b) the increase of radiation near the poles, and (c) the effects of solar particle events (the most important one occurring in early November 1992). This data also provides information about the dose and the quality factor of the radiation to which the cosmonauts were exposed during different missions. These data are compared with measurements obtained using a solid state detector. [Copyright &y& Elsevier]

Abstract: Ambient dose-equivalent results from an in-flight comparison between different tissue-equivalent proportional counters and silicon diode spectrometers from seven European institutes are presented and compared with calculations using the EPCARD computer program. The measurements were performed on 40000 and 32000ft in narrow target areas at latitudes and . Keeping the altitude and geographic position almost constant provided unique conditions for comparisons. The different measuring systems as well as the calculations are in remarkably good agreement, with an average standard deviation in the ambient dose equivalent between 6% and 21%. The ratio between calculated and measured ambient dose-equivalent rates varies between 0.91 and 1.09, with an average of . Nevertheless some systematic differences in the experimentally determined ambient dose equivalent and its low-LET and high-LET components are noticed and discussed. It is concluded that the standard deviation between different instruments can through optimization and harmonization of the calibration procedures be reduced by up to a factor of two. [Copyright &y& Elsevier]

Abstract: This paper presents a measurement campaign carried out in six medical electron linear accelerator facilities to evaluate occupational exposure associated with photons and secondary neutrons for several encountered configurations. No strong correlation between dose and configuration has been observed. Assuming realistic hypotheses, the annual effective dose to staff due to external exposure has been estimated to 0.9mSv, 54% associated with the decay of activation products and 7% due to exposure to leakage neutrons. [Copyright &y& Elsevier]

Abstract: Following a radiological accident on 11 March 2006 in an industrial irradiation facility involving one victim, a physical dosimetry was reconstructed using on site measurements and numerical simulations in order to estimate as accurately as possible and as quickly as possible the dose received and its distribution throughout the organism so that doctors may fine tune their diagnosis and prescribe the most suitable treatment. The data compiled from the experimental reconstruction resulted in a first estimation of the distribution of the dose in the victim''s organism. The numerical simulations indicated a dose gradient corresponding to a factor of 2 in anteroposterior and between the pelvis and the skull. [Copyright &y& Elsevier]

Abstract: This paper presents the current state of a project from the laboratory of ionizing radiation dosimetry of the IRSN (France) concerning the development of an instrumented anthropomorphic phantom for the direct measurement of the effective dose. Contrary to other applications fields where anthropomorphic phantoms are currently used (radiotherapy dose control or spatial studies), the main challenge of this project is to develop small detectors to place inside the phantom sensible to the low-dose rates found at workplaces. A numerical study for photon irradiation fields has proved the feasibility of such an instrument and has determined the positions of the detectors for each organ in order to correctly evaluate the effective dose. Some results of this numerical study are presented here as well as a preliminary schematic description of the prototype detector. [Copyright &y& Elsevier]

The European Radiation Dosimetry Group (EURADOS) is a network of organizations and scientists promoting research and development in the dosimetry of ionizing radiation, contributing to harmonization in dosimetry practice across Europe, and offering education and training in areas relevant for dosimetry. As a registered non-profit association under German law, EURADOS is currently running eight active working groups (WGs): WG2 on "Harmonization of Individual Monitoring", WG3 on "Environmental Dosimetry", WG6 on "Computational Dosimetry", WG7 on "Internal Dosimetry", WG9 on "Dosimetry in Radiotherapy", WG10 on "Retrospective Dosimetry", WG11 on "Dosimetry in High-Energy Radiation Fields", and WG12 on "Dosimetry in Medical Imaging". This paper presents recent scientific results obtained within these working groups, and additionally highlights the role of EURADOS as an organization which contributes to the development of a systematic strategy of radiation protection research in Europe. [ABSTRACT FROM AUTHOR]