Measurement of radiation exposure of the staff of jets by means of thermoluminescent detectors

The effect of cosmic radiation exposure to the staff and passengers of transport jets flying in the height of 9 to 17 km was investigated. The sources of radiation fields in upper atmosphere are reviewed, their average contributions and periodic variations are summarized. The characteristics of flights of transports, the take-off and landing are taken into consideration for the estimation of exposure doses as correction factors for the nominal heights and flying times. Theoretical considerations are compared with the data measured on board of TU-154 jets of Hungarian Airlines MALEV using thermoluminescent dosimeters of type CaF2:Mn. The average exposure of aircraft staff is approximately twofold of that under terrestrial conditions. As the MALEV flights are regularly short, mostly inside Europe, comparison with data from the literature concerning mainly intercontinental flights, supports the present results. (D.Gy.)