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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]

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]