An integrating thermoluminescent Rn daughter personal dosimeter

An integrating Rn daughter dosimeter using conventional Dy-doped CaSO4 thermoluminescent (TL) material has been developed for use as a personal monitor. The dosimeter was found to have a linear response over the range 0.5 WL-h to 25 WL-h and to be insensitive to the state of equilibrium of the Rn daughters. The use of the dosimeter to monitor both 222Rn and 220Rn daughters is described. The limiting sensitivity of the dosimeter, at a sampling rate of 1 L min-1, was determined to be 0.1 WL-h for 222Rn daughters and 0.5 WL-h for 220Rn daughters. The application of the thermoluminescent dosimeter (TLD) to occupational monitoring of 222Rn and 220Rn daughters is discussed.