Personnel dosimetry intercomparison studies

Personnel Dosimeter Intercomparison Studies (PDIS) have been conducted at Oak Ridge National Laboratory's DOSAR Facility. The third PDIS was held during the period March 15-16, 1977, and the fourth PDIS was held during the period March 14-16, 1978. Several independent organizations participated in these intercomparisons using TLD albedo, NTA film, and track-etch dosimeters for the neutron measurements and TLD and film dosimeters for a gamma measurements. The dosimeters which were shipped to the DOSAR Facility, were exposed at the Health Physics Research Reactor (HPRR) to neutron dose equivalents of the order of 500 mrem, produced by operating the HPRR at a power level of two watts. The HPRR, used unshielded, with a 12-cm-thick Lucite shield or a 13-cm-thick steel shield, provided three well-documented neutron and gamma-ray spectra. For the third PDIS the participants measured neutron dose equivalents of 675 ± 168 mrem, 721 ± 186 mrem, and 558 ± 307 mrem for the unshielded, steel-shielded and Lucite-shielded configurations, respectively. For the gamma dose equivalent measurements, the results were 25 ± 14 mrem, 25 ± 14 mrem, and 83 ± 35 mrem for the same exposure configurations. Only preliminary results for the fourth PDIS are available; however, the results seem to be similar to those of the previous study. (author)