Environmental monitoring by CaSO4:Dy TL dosimeters

The thermoluminescent dosimeters of high sensitivity are useful for monitoring the area near nuclear installations. CaSO4:Dy TL dosimeters have high sensitivity and low fading so that by means of them the dose from the background can be measured with an accuracy of 10-20%. An increase of 2 mR in the background can be observed and doses as high as 1000R can be registered with an accuracy of 5%. The measuring method and results are reported here. For two years these CaSO4:Dy dosimeters have been successfully used at the site of the Central Research Institute for Physics. (K.A.)