Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

Fergus R. W.
Health Physics: August 1970
Papers: PDF Only

A personnel hand and shoe monitor, PERCI {derived from PERsonnel Contamination Instrumentation), has been developed to provide simultaneous detection of alpha, beta and/or gamma contamination. Automatic operation provides uniform survey sensitivity that is independent of the user. Logic circuitry prevents incomplete surveys and causes “go” or “no-go” instructions to be flashed on an illuminated display panel. Alpha, beta and/or gamma events for each channel are detected with a large area gas flow detector and pulse separation circuitry. A unique background compensation feature implements statistical computation for each survey by comparing the actual number of events during the survey cycle with a number predicted from the background events preceding the cycle. Reliable operation with stable calibration is assured with solid state circuitry and appropriate feedback. Consistent performance with infrequent false alarms characterizes the operation of this monitor. Sensitivity has been demonstrated on many occasions when the monitor has detected contamination on the user that could not be located with conventional survey instruments.

©1970Health Physics Society