Instruments for monitoring airborne radioactivity

Abstract

The author reviews some of the methods and instruments developed at Harwell Laboratory for monitoring airborne particulate activity in (1) ducts and stacks which might carry radioactive aerial effluents; (2) working areas within nuclear facilities where a hazard from airborne radioactivity might exist; and (3) the breathing zones of individuals who might be exposed. Instruments for both real-time and retrospective measurements are described. Particular attention is given to instruments using alpha spectrometry and individual compensation against each radon and thoron daughter; discrimination by decay rate; extended-range monitors and combined alpha beta monitors.<>