NTS:

Abstract

This report summarizes the Spring 1991 2-m Box experiments that were performed at the These studies were sponsored by the Defense Nuclear Agen c y (DNA) under the Radiation Program to obtain mea s ured data for benchmarking the Adjoint Monte Carlo Code System, MASH, Version 1.0. The MASH code system was developed for the Department of Defense and NATO for calculating neutron and gamma - ray radiation fields and shielding protection factors for armored vehicles and military structures against nuclear weapon radiation. In the 2 - m Box experiments, neutron and gamma - ray dose rates and reduction factors were measured in the free - field and as a function of position on an anthropomorphic phantom that was placed outside and inside a borated polyethylene lined steel - walled 2 - m box. The data were acquired at a distance of 400 - m from the APRF reactor. The measurements were performed by APRF, Armed Forces Radiobiology Research Institute (AFRRI), Etablissement Technique Central de l' Armement (ETCA), and Harry Diamond Laboratory (HDL). Calculations were carried out by the Oak Ridge National Laboratory (ORNL) and Science Applications International Corporation (SAI C ). The purpose of these experiments was to measure the neutron and gamma-ray dose rates as a function of detector location on the phantom for cases when the phantom was in the free - field and inside of the box. Neutron measurements were made using a BD - 100R bubble detector and gamma - ray measurements were made using thermoluminescent detectors (TLD). C alculated and measured data were compared in terms of the C / M ratio. DNA mandated that C / M values of ±20% defined acceptable limits for qualifying the MASH code in replicating integral parameters. factors were carried out by and good