Survey instrument response to beta radiations

It is noted that available survey instruments do not have the beta measurement characteristics needed for accurate dose rate assessments. Such instruments have severe angular and energy dependence. In addition, beta measurements often require corrections for the source geometry response of the detector to permit accurate assessments. Studies were performed to characterize present instruments and to determine optimum characteristics for a field instrument. Results of the studies were used to specify and procure an instrument with improved characteristics. The results of the studies and the design of the instrument are described. It is shown that a thin collection volume improves the instrument response. This was verified by the development of a prototype instrument. The instrument is microprocessor-based, permitting corrections for source geometry and automated compensation for ambient temperature and pressure changes