I want to make it more clear
From the output of stress report in OPE, SUS, and OCC load cases in any node check the allowable whether it will meet one of F*SMYS*T, 0.8*SMYS, 0.9 SMYS.
If it meets F*SMYS*T we can say %max. stress comes from hoop stress
If it meets 0.8*SMYS we can say %max. stress comes from longitudinal stress
If it meets 0.9*SMYS we can say %max. stress comes from equivalent stress
Caesar II only reports the highest % stress between three.