Calculation of Minimal Detectable Activity for Scintillation Detection Systems

Abstract

This paper analyzes the statistical approach to the determination of minimum detectable radioactivity for nuclear medicine counting data. Based upon measurements of the background level and detector counting efficiency this method allows calculation of the counting time necessary to detect a specified minimum amount of radioactivity. This method is important both in the application of bioassay measurements of radiation workers for measuring thyroid burden and in the measurement of radioactive wipe test samples.