In order to prevent the overhaul accident of crude oil storage tank

the improved job hazard analysis（JHA） method is used to analyze the overhaul risk of crude oil storage tank. First

analyze the overhaul operation stage and operation steps of crude oil storage tank

identify the hazardous and harmful factors in the operation process based on the categories of accident causes

and then use the risk grade evaluation method to semi quantify the risk grade of each operation step. Finally

formulate corresponding safety control measures for different hazardous and harmful factors. Taking the overhaul of a crude oil storage tank in Zhoushan as an example

the JHA method was improved. The results showed that there were 20 operation steps and87 hazardous and harmful factors in the tank overhaul and tank cleaning operation phase. The risk level determined that the risks were 15 IV risks

19 III risks

0 II risks

and 0 I risks

indicating that the safety risks in the tank overhaul and tank cleaning operation phase were controllable. This method could comprehensively identify the hazardous and harmful factors in the tank overhaul operation. And the risk level is basically consistent with the actual situation

which can effectively achieve the hierarchical management and control of tank overhaul risk and improve the operation safety management level of oil storage enterprises.