Assessing exposure to cosmic radiation during long-haul flights
Bottollier-Depois, J.F.; Chau, Q.; Bouisset, P.; Kerlau, G.; Plawinski, L.; Lebaron-Jacobs, L.
IRPA-10: 10. international congress of the International Radiation Protection Association Hiroshima (Japan) 14-19 May 2000, P1a-39.
Publié également dans Radiation Research (2000), 153, 526-532
The assessment of exposure to cosmic radiation on board air craft is one of the preoccupations of organizations responsible for radiation protection. Cosmic particle flux increases with altitude and latitude and depends on the solar activity. The exposure has been estimated on several airlines using transatlantic, Siberian and transequatorial routes on board subsonic and supersonic air crafts, to illustrate the effect of these parameters. Measurements have been realized with a tissue equivalent proportional counter using the microdosimetric technique. Such a system provides the absorbed dose, the ambient dose equivalent, the mean quality factor and the dose distribution as a function of lineal energy. Data have been collected at maximum solar activity in 1991-92 and at minimum in 1996-98. The lowest mean dose rate measured was 3 muSv.h-1 during a Paris-Buenos Aires flight in 1991. The highest was 6.6 muSv.h-1 during Paris-Tokyo flight using Siberian route and 9.7 muSv.h-1 on Concorde in 1996-97. 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 mSv for least-exposed routes and 5 mSv for more exposed routes.