On the retrospective dose from X-ray interference radiation during work on military radar equipment

In radar equipment, mainly vacuum electron tubes are used to generate the high-frequency pulses, which are to be treated as X-ray sources of interference because of the necessary high operating voltage. Due to the diverse range of applications and wide power range of military radar equipment, many different designs and types of electron tubes are also encountered there, whose possible emission of X-ray interference radiation at workplaces of technical personnel must be considered. In a broad investigation, the possible exposure of employees to radar equipment of the German Federal Armed Forces and the former National People's Army of the GDR is examined for the entire period of use since the end of the 1950s. The technical analysis and available measurement records show that X-ray exposure of technical personnel can be ruled out for the majority of radars. The dose rate values registered for certain types of radar equipment show a broad distribution, so that dose considerations based on maximum values result in a considerable overestimation of the doses received on average.