Tritium behavior in the environment and absorption dose

1)利用UFOTRI代码计算了核反应堆假想事故释放氚的辐射吸收剂量。如果氚化水以1Bq/秒的速率释放1小时。从100m高空堆叠进入环境，在顺风2km处地面最大吸收点的吸收剂量为8E-16 ~ 9E-15Sv。这些吸收剂量值的差异主要发生在不同的环境温度和湿度条件下。进一步的调查正在进行中。2)在核反应堆氚处理实验室对安全处理方法进行了检验。对于工人的安全保护而言，机房监控系统比烟囱监控更重要。有人建议，在发生事故的情况下，在短工作时间内，室内空气中的氚浓度应估计比攻击空气中的氚浓度高30-40倍。3) 50毫西弗/年的辐射吸收剂量对氚搬运工人真的安全吗？1毫西弗/年的辐射剂量对核设施周围的公众也是安全的吗？日本人每年的自然辐射吸收剂量为1.5mSv，医疗辐射吸收剂量为2.3mSv，世界平均水平为2.4mSv/年。氚化水的摄入量为6x10E7Bq，为1mSv/y。将6x10E7Bq的氚化水分批喂给老鼠，对身体没有明显的影响。4)通过重水释放试验研究了影响水稻和甘薯中氚行为的转移因子。

1) The radiation absorption dose of tritium in an imaginary accidental release from a nuclear reactor was calculated using UFOTRI code. If tritiated water was released for 1hour at a rate of 1Bq/sec. into the environment from the stack of 100m in high, the absorption doses at the maxim point, 2km of downwind, on the ground were from 8E-16 to 9E-15Sv. These differences of absorption dose values were primarily occured with different temperature and humidity conditions in the environment. Further investigations are now underway.2) Safety handling methods were examined in the tritium handling laboratories of a nuclear reactor. Room monitoring system was more important for safety protection purpose of workers than stack monitoring. It was suggested that, in case of accident, tritium concentration in room air in a short duration of working time should be estimated 30-40 times higher than that in attack air.3) Fifty mSv/y of radiation absorption dose is really safe for tritium handling workers? One mSv/y radiation dose is also safe for the public around nuclear facilities? Annual radiation absorption dose in Japanese is 1.5mSv from natural radiations, 2.3mSv from medical radiation, and the world average is 2.4mSv/y. The intake of tritiated water, 6x10E7Bq, gives 1mSv/y. The administration of total 6x10E7Bq of tritiated water in lots to a mouse produced no recognizable somatic effects.4) Transfer factors on tritium behavior in rice and sweet potato were examined in heavy water release experiments.