An integrated software package for control and data analysis of aerial gamma spectrometric system (AGSS)

Quick determination of the profile of ground contamination following a potential fallout of radionuclides over a wide area around a nuclear power plant in a post accident situation is of great importance for emergency management. An aerial gamma spectrometry system (AGSS) developed for this purpose consists of high efficiency NaI(Tl) scintillation detectors, an 8085 microprocessor based 256 channel scanning pulse height analyzer, a global positioning system (GPS) and a radio modem. In an aerial survey, the AGSS mounted in an aircraft scans the radionuclides contamination on ground as it simultaneously collects spectral and positional information in contiguous time intervals. For the programmed functioning of the AGSS, an integrated software package has been developed using micro soft visual basic operating under MS Windows. The software package correlates the spectral and positional data acquired by the AGSS in test flights over contaminated ground and maps the activity profile on-line onto a digitized site-map of the area. The package also facilitates simultaneous transmission of the information to a emergency control centre by means of the radio modem and its parallel processing. Several features of the software like zooming of a selected area for close scrutiny, on-line assessment of the radiological status of any desired area just with a mouse click etc., are incorporated in the package to make it comprehensive, user friendly and as a powerful aid in quick decision making process. The package also includes interactive communication with the AGSS for setting up various system parameters, initiation of the monitoring, on line interruption in monitoring to perform the processing of current spectrum for checking channel drift etc. The system software has been tested by deploying the system in a helicopter and flying over areas with simulated ground contamination in three successive aerial exercises. (author)