Situations where foreign materials do not require re-inspection

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We are now facing a somewhat special situation: a tower vessel was designed using the foreign material grade S32205. Initially, it was agreed that the calculations would be based on the allowable stress values specified in the national standard S22053, with subsequent rechecking of the chemical composition and mechanical properties in accordance with relevant regulations. However, after the customer adjusted the parameters, the tower has now become a device of a different category, with a working pressure of 0.06 MPa. For this reason, the manager hopes to have the materials retested to eliminate that, which could save some costs. To better match the characteristics of materials used abroad, the allowable stress was replaced with that of SAME; however, the allowable stress for S22053 cannot be found in Section D, so the stress value for S31803 was used instead. I always feel that it’s a bit awkward to use foreign allowable stress values with the design methods based on national standards. Moreover, although tower vessels are not in the same category, the requirements for them should be stricter. But the manager meant that since it’s outside the category, there’s no need to follow the tolerance specifications. I hope to hear the opinions of experts here.