DOSE-ATTENUATION VARIATION WITH INCIDENT GAMMA-RAY ENERGY IN TWO-LEGGED CONCRETE AND STEEL DUCTS
Abstract
Gamma-ray dose-attenuation factors were measured in concrete and steel ducts. For concrete, 3-foot-square and 11-inch-square ducts were used with Au(198) (0.412 Mev), Cs(137) (0.662 Mev), and Co(60) (1.25 Mev) gamma -ray sources. Attenuation factors for given geometries were compared as a function of incident gamma-ray energy. The relative effectiveness of steel and concrete ducts of a given geometry was determined. The attenuation factor decreases monotonically with increasing energy in concrete ducts. In the 11-inch steel duct the attenuation factor for the high-energy source (Co(60)) was greater than for the low-energy source (Cs(137)). In comparing the 11-inch concrete and 11- inch steel ducts, it was found that dose rates in the concrete duct were higher by a factor of about 2. Measured attenuation factors were compared with values obtained using a computer code based on the albedo concept. It was found that calculated attenuation factors agree to within + or -30% of the measured attenuation factors.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1966
- Accession Number
- AD0630697
Entities
People
- J. M. Chapman
Organizations
- Naval Facilities Engineering Service Center