Neutron spectra and dose equivalent inside reactor containment

A study was undertaken to measure, characterize and evaluate neutron radiation dose equivalent rates and neutron energy spectra at six nuclear power sites in the U.S.A. The measurement data include: 1) neutron dose and dose equivalent rates inside and outside containment buildings; 2) neutron spectral and flux distributions; 3) monitoring with albedo, film and fission fragment neutron dosimeters; and 4) correlations of dosimeter data and instruments with flux and spectral distributions. A multisphere spectrometer system consisting of five polythene spheres of various sizes was used to unfold the neutron spectrum. Various results are presented for tissue equivalent proportional counters (TEPC) and it is shown that monitoring instruments read a factor of approximately 2 higher than reality in well scattered neutron fields inside containment buildings. (UK)