Dear Raja,

Assume for ASME B31.3 code, the correct combination for (OCC)*** are:
SUS+(max wind)
SUS+(U = earthquake)
SUS+(F = concetric force due to PSV discharge)


L?? W+P+T+D+U1 (OPE)
L?? W+P+T+D-U1 (OPE)
L?? W+P+T+D+U2 (OPE)
L?? W+P+T+D-U2 (OPE)
L?? W+P+T+D+U3 (OPE)
L?? W+P+T+D-U3 (OPE)
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L?? W+P+T+D+F (OPE)
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to have U1,-U1, U2, -U2, U3, -U3, and F use the same like L11~L14. The case number drop starting from L7 if we include U and F. Note U1, U2, and U3 could occur in the same time which will generate many load cases if you want in complete combination.