AN EXPERIMENTAL EVALUATION OF ROOF REDUCTION FACTORS.

Abstract

A major portion of the radiation dose received within a structure is due to the fallout deposited on the roof. The report describes experiments conducted to measure the attenuation introduced by the roof to this radiation as a function of the mass thickness and the solid angle fraction subtended by the roof source to a detector in the structure. The first series of experiments conducted on a roof of an inhomogeneous mass distribution, determined the attenuation introduced by mass thicknesses of 0, 48.6, 97.2, and 145.8 psf. Qualitative agreement between data from these experiments and calculated values made in an infinite homogeneous media is good. Measured dose rates from a rectangular source array of eccentricity 1.5 agreed within 10 per cent with a circular source array subtending the same solid angle fractions. A second series of experiments designed to closely simulate the analytical model used in the theoretical calculations was conducted for mass thicknesses of 0, 48.6, 97.2, and 145.8 psf. A maximum discrepancy of 15% is shown between theory and experiment for all mass thicknesses investigated. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1966
Accession Number
AD0645661

Entities

People

  • C. Mcdonnell
  • J. Velletri

Tags

DTIC Thesaurus Topics

  • Agreements
  • Attenuation
  • Detectors
  • Dose Rate
  • Eccentricity
  • Radiation
  • Radiation Effects
  • Test And Evaluation
  • Thickness

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Nuclear Civil Defense.
  • Solar Physics