Safety assessment of VHTR hydrogen production system against fire, explosion and acute toxicity

Murakami, Tomoyuki; Nishihara, Tetsuo ; Kunitomi, Kazuhiko 

Japan Atomic Energy Agency has been developing a nuclear hydrogen production system by using heat from the Very High Temperature Reactor (VHTR). This system will handle a large amount of combustible gas and toxic gas. The risk from a fire, an explosion and an acute toxic exposure caused by an accident of chemical material leakage at the hydrogen production system is assessed. It is an important subject in design to ensure the safety of the nuclear plant and the risk for the public health to be sufficiently small. This report provides the basic policy about the safety evaluation on the accident of the fire, the explosion and the toxic material release from the hydrogen production system near the nuclear plant. Based on this policy, we performed a safety analysis of the GTHTR-300C. This analysis provides us with useful information about a separation distance from the nuclear plant to the hydrogen production system and a prospect that the accident of the hydrogen production system does not significantly increase a risk for the public.