Dear 1/2mario,

Onshore pipeline for gas transmission: ASME B31.8
Offshore pipeline: ASME B31.8 chapter VIII

The value of allowables can be found in c2quick.pdf file located in Caesar directory. For ASME B31.8 chapter VIII the stresses checked simultaneously for Hoop, Longitudinal, Equivalent stress in OPE, SUS, and OCC load cases. You will be able to know which stress between three is the maximum one from the allowable.