Gamma dosimetry with ultraviolet-transmitting plexiglas

The effect of gamma radiation from two previously uninvestigated sources, namely a manganese isotope cell and a nuclear reactor after shutdown, on the optical properties of ultraviolet-transmitting plexiglas was studied to determine the possibility of using this material for dosimetry.The relation between the optical density and the total integrated dose from both sources was found to be linear, thus favoring the use of the plastic for dosimetry. However, for decay gammas from the reactor, the relation is linear only when the plastic is kept at a low temperature (0°C) during exposure to radiation.The effect of bleaching was also investigated. It was found that lowering the temperature preserves the induced optical density for a long time. Storing under vacuum did not affect the rate of bleaching to a great extent.