| produced in nuclear industry.HTO,whether in liquid or gaseous state, is a very important radioactive effluence in nuclear power plant.HTO is absorbed easily by human body and lead to internal irradiation.Thesis researched the concentration of the HTO and OBT of the professionals and the public body , calculating the HTO and OBT dose.We researched the factors which influenced measurement of urine tritium, comparing four sample pretreatment methods, directly distill stripping, adding KMnO4 to distill stripping, adding K2S2O8 to distill stripping, directly distill stripping together with adding H2O2.The results shown that the method of adding K2S2O8 to distill stripping could use to be measuring total HTO, the method of adding KMnO4 to distill stripping could use to be measuring HTO, the method of directly distill stripping together with adding H2O2 could use to be measuring large number of samples in a short time.We researched the concentration of urine tritium of workers intaking 3H. The results shown that the concentration ratio of organically bond tritium to total tritium was from 0.93% to 9.14% in the normal work condition, with an average of 4.02%, the accumulated-effective doses of HTO to total dose was 87.02%, the accumulated-effective doses of OBT to total dose was 12.98%, so the proportion of organically bond tritium could not be neglected. Through profile, we researched the biology elimination half-time of HTO and OBT. The biology elimination half-time of HTO in the human body was on an average of 12.41 days, the biology elimination half-time of OBT in the human body was an average of 40.19 days .We researched the concentration of urine tritium of public body. The results shown that the concentration ratio of organically bond tritium to total tritium was from 1.22% to 8.63%, with an average of 5.20%.The dose was 2.05×10-7Sv,not more than the limits(1mSv). In addition,we used the method of ICRP recommended and the Chinese standard to estimate the dose of the HTO and OBT, the difference was found between 5% and 6%.Using the air samples collected in the nuclear power, we researched the concentration of HTO and OBT. The results shown that the maximum of annual intake of HTO is 3.73×104Bq, the minimum of annual intake of HTO was only 1.87×104Bq, all of the annual intake of total tritium were much smaller than the annual intake limit of 3×109Bq.In normal working conditions and hours, accumulated-effective doses that respiratory and skin means the annual intake of tritium caused was no more than 2.04×10-7Sv, including working hours and resting and sleeping time, total accumulated-effective doses of tha staff was no more than 2.53×10-7Sv,far less than the limit of annual dose 20mSv.Based on daily food consumption and dietary composition for Chinese reference man and the concentration of HTO and OBT around environment Base,a mode of intake estimation and dose assessment via various food chains was made in this paper. The results shown that the public average annual intake estimation of HTO was 1.98×104Bq ,and the public average annual intake estimation of OBT was 1.02×104Bq.The public average annual accumulated-effective doses of 3H was 1.27μSv.In practical work, some workers continued to intaking tritium for a period of time, we used body fluid metabolism and nuclide metabolism dynamics model to research the accumulation of internal tritium, metabolism and the accumulated-effective doses under a sustained intake of tritium conditions. The results shown that while estimating of HTO retention, there were difference between less than 1%; while estimating of OBT retention, there were difference to be 39.04%...
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