Calibration of a solid state nuclear track detector for the measurement of indoor levels of radon and its daughters.

Time-integrated measurements of environmental radiation levels are commonly carried out using solid state nuclear track detectors (SSNTD). These detectors are particularly suitable for monitoring indoor radiation, however they should be calibrated for the measurement of the levels of radon (Rn) and its daughters likely to be found in dwellings. This paper reports the results of experiments conducted to calibrate cellulose nitrate film. LR-115 type II, which is used for the measurement of Rn levels in indoor environments of dwellings in India. The detector was exposed to varying concentrations of Rn inside an exposure chamber both in Bare and in Cup with membrane modes. We obtained calibration factors of 1.05 x 10(-3) tracks cm2 day-1 per pCi m-3 (2.84 x 10(-2) tracks cm-2 day-1 per Bq m-3) and 4.8 x 10(2) tracks cm-2 day-1 per WL of Rn.