Dose Delivered by Unit Amount of Tritium Released into the Environment
Dose conversion values (DCV: Sv/kg-Tritium release) associated with a release of tritiated hydrogen (HT) to the atmosphere have been studied in the field experiment performed at Chalk River Laboratories in Canada in 1987. For a near ground-level release of HT, DCVs of 2×10<SUP>-2</SUP> and 3×10<SUP>-3</SUP> Sv/kg-Tritium were evaluated at distances of 100 and 400m on the mean plume centerline, respectively. An important finding was that less than 1% of the respective doses was attributed to the primary HT plume (by submersion) and the rest to HTO (by inhalation plus skin absorption) which was formed due to conversion of the HT to HTO in the environment. A comparison to a postulated HTO release under experimental conditions predicted that corresponding dose conversion values may reach approximately 90 and 70 times greater than those of the HT release at respective distance. Extrapolation of these experimental dose conversion values into those in maximum-exposed conditions (MEC) was made. It was predicted that the ratios of dose conversion values between HTO to HT releases under the MEC were about 20 at 100m (6 at 400m), though a release of HTO is approximately 25, 000 times more radio-hazardous than a release of HT if no conversion of HT to HTO is assumed to occur in the environment. The present results were compared with those of the French HT release experiment in 1986.
- Journal of nuclear science and technology
Journal of nuclear science and technology 34(2), 176-184, 1997-02-25
Atomic Energy Society of Japan