Abstract: In order to deal with the inconsistency of element level allocation in CRM, a new risk matrix analysis method, considering the cognitive uncertainty of risk decision makers, was proposed. Firstly, the risk indexes were calculated by adopting the “multiplication principle” of level numbers. The risk indexes were used as the basis for level allocation of risk matrix. Secondly, the decision maker's attention coefficients were incorporated to describe the influences of potential risks. The traditional risk index calculation model was modified by the attention coefficients. Then, the modified continuous probability consequence diagram (CPCD) was mapped to the CRM. The risk matrix element levels were allocated based on the principle of maximum risk index. The risk level quantification process of a certain type of cryogenic liquid hydrogen filling system on a certain space launching site was analyzed by this method. The results show that risk level allocation schemes of different filling procedures can be obtained with the modified risk index model,and that the cognitive uncertainty of risk decision makers has an influence on risk level allocation of the cryogenic liquid hydrogen filling system.

Key words: conventional risk matrix(CRM), risk index, cognitive uncertainty, space launch site, cryogenic liquid hydrogen filling system