NORSOK M-710 is the gold standard for RGD qualification of HPHT elastomers. Test fixtures expose O-rings to methane or 90/10 He/CO₂ at 150°C/15 MPa for 72 h, then decompress at 20 bar/min. Post-test, cross-sections must show no internal cracks >80 µm. Only seals passing four consecutive lots earn the official NORSOK compliance stamp used by Equinor, Shell, and TotalEnergies. https://globalsealstech.com/product/rgd-rapid-gas-decompression-o-rings/