Apparent dose equivalents resulting from severe heating of film dosimeters

Unusual reported dose equivalents due to high-energy photons for two individuals prompted the investigation of the effects of severe heating conditions expected in closed vehicles during southwestern summer months on commercial film dosimeters. A historical review of dosimetry records revealed several additional reported high-energy photon exposures for individuals using only beta-emitting radioisotopes during hot summer months. Between 20-100% of experimentally heated badges had apparent dose equivalents exceeding the minimal detectable dose equivalent that were not flagged as being heat damaged or having unusual exposure patterns by the dosimetry companies. Reported dose equivalents for these badges were as high as 2.1 mSv.