The testing of radiation protection instruments used for the monitoring of surfaces contaminated with radioactive material

A national scheme for the calibration of protection instruments is being prepared. The National Physical Laboratory will maintain suitable primary standards of dose. Test procedures compatible with the national scheme are recommended for surface contamination monitoring instruments used for radiation protection in medical environments. Three types of radiation tests are described: (1) Standard calibrations carried out at laboratories holding secondary standards supplied by the NPL: (2) Laboratory checks to verify the calibration annually, using facilities available in most hospital physics departments: (3) Operational checks in the department where the instrument is normally used, employing available facilities. Permissible variations in instrument readings and typical response data for various types of detector are given. (author)