Gammafet - fixed-wing gamma survey for the detection of radioactive materials. Finnish support to IAEA

Finland has the operational capability to make airborne gamma ray measurements in emergency situations. The original purpose of airborne radiation mapping was to determine hazardous areas containing radioactive fallout after nuclear accidents or the use of nuclear weapons. Regular exercises are held annually to keep operational functionality at high level for this purpose. The knowledge and achieved practice can easily be extended to use in international radiation monitoring campaigns. The presented guidelines are based on Finnish knowhow, but it is not limited to use with Finnish equipment. The report describes the method and its usability in detecting the chain of nuclear material production using aerial gamma ray measurements. Technical details are given on how to manage measurement tasks, and information is also given on what is detectable from an aeroplane and how it is detected. The ability to use the airborne detection system has been tested to reveal the use of undeclared nuclear material. Various scenarios were considered with which to reveal clandestine nuclear material production, enrichment, and nuclear waste trails. The exercises arranged during this programme show that it is possible to reveal such clandestine activities. The fixed-wing gamma measurement technique developed under this contract is ready for detecting significant amounts of nuclear material efficiently and cost effectively. Large areas can be screened to find suspicious sub-areas for more accurate inspection. The approximate cost of screening is USD 17.4 per square kilometre. (orig.)