ANNUAL PER-CAPITA DOSES OF THE JAPANESE FROM COSMIC RADIATION EXPOSURE IN COMMERCIAL FLIGHTS

Annual per-capita aviation doses of the Japanese people from commercial flights were calculated for 6 years period from 2009 (solar minimum) to 2014 (solar maximum) using the flight routes provided by major Japanese airlines. For international flights, the area other than Japan was separated to nine regions and collective effective doses were estimated from the number of the Japanese flyers to those regions multiplied by the calculated aviation route doses to representing cities. Collective effective doses for domestic flights were estimated as the products of the collective distances (man km) and the unit-distance route dose determined from three major routes. The flyer-average, annual per-capita dose from the international flights was estimated as 54 μSv and one-flight average dose from the domestic flights was 1.7 μSv. As the Japanese population average, the annual per-capita dose was 8.3 μSv, of which nearly 90% was from the international flights.