Dynamic evaluation of environmental impact due to tritium accidental release from the fusion reactor

•Dynamic tritium concentration in the air and human body evaluated on the time scale.•Different intake forms and relevant radiation dose assessed to find out the potential relationships.•HT and HTO release amount limits for arbitrary accidents proposed for the fusion reactor according to dose limit.

As one of the key safety issues of fusion reactors, tritium environmental impact of fusion accidents has attracted great attention. In this work, the dynamic tritium concentrations in the air and human body were evaluated on the time scale based on accidental release scenarios under the extreme environmental conditions. The radiation dose through various exposure pathways was assessed to find out the potential relationships among them. Based on this work, the limits of HT and HTO release amount for arbitrary accidents were proposed for the fusion reactor according to dose limit of ITER. The dynamic results aim to give practical guidance for establishment of fusion emergency standard and design of fusion tritium system.