By the Area Specific Stripping (ASS) method for NaI gamma detectors it is possible in a simple way obtain the parameters (stripping factors) that are needed for being able to discern between natural radioactivity signals and signals from manmade radioactivity and radiation anomalies in general. The method has earlier been tested only for a few sets of Danish AGS and CGS data. 1. One of the goals of the project has been to investigate to which extent is it possible to use the ASS method for a number of different sets of gamma spectra recorded by different teams with different types of equipment in different environments. 2. Another goal of the project has been to investigate why (earlier) one sometimes got oddly-looking ASS parameters that worked correctly when seen from a mathematical point of view but seemingly had no physical meaning. 3. It was also a goal that the successful parts of the ASS technique should be developed to a point where other Nordic teams could use it for practical purposes.
gamma spectrometry, stripping, lost sources, height dependency