Flange rigidity is one of the criteria that would need to be met when rating older equipment to later Codes. The rigidity check used to be in Non-mandatory appendix S then later moved into Appendix 2. Our recommendation is to perform this check even for older flanges.
As INSPECT contains all of the functionality of COMPRESS, it is a good option for fabrication shops that also perform rerates for their clients during turn around periods. Many owner/operators have inspection data and send it to the fabricator so they can assess the vessel since the equipment is in the shop for work.