Abstract: In order to reduce the occurrence of fire and explosion accidents ， a risk assessment approach integrating Bayesian network and bow-tie analysis was proposed. Firstly， the fault tree is established and transformed into Bayesian network. Then the weak points which might lead to accidents can be pinpointed by calculating the importance of each basic event. The bow-tie analysis is given on the weak points to work out the precautions and control measures， and the reduction of accident frequency is calculated after taking control measures for the weak points. The reasons for such accidents can be found accurately by this approach， which helps to take appropriate precautions and control measures so as to effectively reduce the occurrence of biomass gasified fire and explosion accidents.

Key words: biomass gasification, FTA(fault tree analysis), Bayesian network, bow-tie analysis, fire and explosion accident