Measurement of cosmic radiation exposure of aircraft crew at commercial aviation altitudes

The measurement results of ambient dose equivalent rate in an aircraft, performed by a standard portable dosimeter, at a non-commercial flight Belgrade - Podgorica at altitudes up to 9000 meters, are shown. By numerical interpolation of the measurement results, a functional dependency of the ambient dose equivalent rate on the altitude of the airplane flight is determined, obtaining a good agreement with the reference values. For commercial airlines in the Balkan region, total ambient dose equivalent, regarding the aircraft crew occupationally exposed to radiation in the course of a flight, was calculated and the maximum permitted number of flight hours per year, was estimated.