skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Determination of the response function for the Portsmouth Gaseous Diffusion Plant criticality accident alarm system neutron detectors

Technical Report ·
DOI:https://doi.org/10.2172/471366· OSTI ID:471366

Neutron-sensitive radiation detectors are used in the Portsmouth Gaseous Diffusion Plant`s (PORTS) criticality accident alarm system (CAAS). The CAAS is composed of numerous detectors, electronics, and logic units. It uses a telemetry system to sound building evacuation horns and to provide remote alarm status in a central control facility. The ANSI Standard for a CAAS uses a free-in-air dose rate to define the detection criteria for a minimum accident-of-concern. Previously, the free-in-air absorbed dose rate from neutrons was used for determining the areal coverge of criticality detection within PORTS buildings handling fissile materials. However, the free-in-air dose rate does not accurately reflect the response of the neutron detectors in use at PORTS. Because the cost of placing additional CAAS detectors in areas of questionable coverage (based on a free-in-air absorbed dose rate) is high, the actual response function for the CAAS neutron detectors was determined. This report, which is organized into three major sections, discusses how the actual response function for the PORTS CAAS neutron detectors was determined. The CAAS neutron detectors are described in Section 2. The model of the detector system developed to facilitate calculation of the response function is discussed in Section 3. The results of the calculations, including confirmatory measurements with neutron sources, are given in Section 4.

Research Organization:
Lockheed Martin Utility Services, Inc., Piketon, OH (United States)
OSTI ID:
471366
Report Number(s):
POEF-LMUS-85; ON: DE97005929; TRN: 97:012371
Resource Relation:
Other Information: PBD: Mar 1997
Country of Publication:
United States
Language:
English