Neutron dosimetry at commercial nuclear plants. Final report of Subtask C: /sup 3/He neutron spectrometer

Technical Report · Sat Sep 01 04:00:00 EDT 1984

OSTI ID:6517869

Brackenbush, L W; Reece, W D; Tanner, J E

In commercial nuclear power plants, personnel routinely enter containment for maintenance and inspections while the reactor is operating and can be exposed to intense neutron fields. The low-energy neutron fields found in reactor containment cause problems in proper interpretation of TLD-albedo dosimeters and survey instrument readings. This report describes a technique that can aid plant health physicists to improve the accuracy of personnel neutron dosimetry programs. A /sup 3/He neutron spectrometer can be used to measure neutron energy spectra and determine dose equivalent rates at work locations inside containment. Energy correction factors for TLD-albedo dosimeters can be determined from the measured spectra if the dosimeter energy response is known, or from direct measurements with dosimeters placed on phantoms at locations where the dose equivalent rate has been measured. This report describes how to assemble a spectrometer system using only commercially available components, how to use it for reactor energy spectrum measurements, and how to analyze the data and interpret the results. Both /sup 3/He and multisphere spectrometers were used to measure neutron energy spectra and dose equivalent at three PWRs and one BWR. In general, the /sup 3/He spectrometer measures higher dose equivalent rates than the multisphere spectrometer. In the energy range from 10 keV to 1 MeV, the dose equivalents measured by the /sup 3/He spectrometer and multisphere spectrometer agree within about 35% for the spectra measured.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6517869
• Report Number(s): NUREG/CR-3610; PNL-4943; ON: TI85001037
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220900* -- Nuclear Reactor Technology-- Reactor Safety
440102 -- Radiation Instrumentation-- Radiation Dosemeters
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CONTAINMENT
DOSIMETRY
EVALUATION
HE-3 COUNTERS
INSPECTION
MAINTENANCE
MEASURING INSTRUMENTS
NEUTRON DETECTORS
NEUTRON DOSIMETRY
NEUTRON SPECTROMETERS
NUCLEAR FACILITIES
NUCLEAR POWER PLANTS
PERSONNEL
POWER PLANTS
PROPORTIONAL COUNTERS
RADIATION DETECTORS
REACTOR MAINTENANCE
SPECTROMETERS
TESTING
THERMAL POWER PLANTS