Design And Development Of A Plastic Scintillator Based Whole Body Beta/Gamma Contamination Monitoring System

Plastic scintillation detectors based whole body beta/gamma contamination monitors are developed for use in radiation facilities. This microcontroller-based multi-detector system uses 13 plastic scintillator detectors, with minimized dead detection zones, monitoring the whole body, and conforming to the contamination limit prescribed by the regulatory authority. This system has the features for monitoring hands, feet, head, and face beta/gamma using contamination monitors and portal exit monitors. It can detect gamma sources at a dose rate of 10 nGyh(-1). The system is calibrated using beta sources Sr-90/Y-90, Tl-204, and Cl-36, and the efficiency is found to be 29%, 22%, and 18%, respectively. The minimum detectable beta/gamma contamination is 0.15 Bqcm(-2), which is significantly less than the minimum detection objectives on head, face, hands, and feet.