Evaluation of the neutron dosimeter used by Martin Marietta Energy Systems, Inc., ability to meet the requirements of the American National Standard for Personnel Neutron Dosimeters (neutron energies less than 20 MeV) ANSI N319-1976

摘要

An evaluation of the neutron dosimeter used by the Centralized External Dosimetry System of Martin Marietta Energy Systems, Inc., was performed, and the dosimeter was shown to meet the requirements of the American National Standard for Personnel Neutron Dosimeters, ANSI N319-1976. This report details the requirements of the Standard, describes the tests performed, and evaluates the results of testing. To demonstrate compliance with the Standard, dosimeters were irradiated with a (sup 252)Cf source while mounted on a standard phantom. Dose was measured using the routine methodology employed by the Centralized External Dosimetry System for neutron dosimetry. The ability to accurately measure neutron dose was compared to specific performance criteria from the Standard. This includes testing the lower limit of detection, upper limit of detection, precision of results, and the capability to detect neutrons in a high gamma dose environment. In addition to neutron exposure, the dosimeters were required to be exposed to environmental factors including temperature extremes, high humidity, exposure to room light, and a drop to a hard surface. Only after exposure to these conditions were the dosimeters read, with results compared to the requirements of the Standard. Normal use factors of routine neutron dosimetry influencing the accuracy, sensitivity, or precision of the dosimetry system were also evaluated to measure their impact on dosimeter response.