A Personnel Radiation Dosimeter with Storage for Preset Alarm and Continuous Readout

The circuit design of a gamma radiation dosimeter is described which permits continuous monitoring of accumulated radiation dosage. An electro-chemical integrating and storage device permits continuous readout in Roentgens followed by a preset audible alarm with an exponential horn tuned for maximum audio output with minimum power input. Any radiation dose rate can be monitored by selecting a G-M detector that gives the desired range. The unit described has a readout range of 200 R and will operate in a radiation field up to 1000 R/hr with an accuracy to within ±5% in an operating temperature range from 0° to 60 °C. The unit weighs less than one pound and has the capability to be clipped to the user's belt, allowing freedom of activity during emergency rescue operations or other hazardous assignment.