In Probabilistic Safety Assessment(PSA),organizational risks contribute greatly to the safety of a nuclear power plant.The paper researches on how to figure out organizational risk in a framework of PSA.On the basis of a conception framework of transmitting organizational structure to a PSA analysis pattern,the paper classifies organizational risk elements.The classified elements are influenced by Performance Shaping Factors(PSF)and are calculated in Human Reliability Analysis.Calculating the PSFs can es...