Hi,
Talking from an EPC point of view, where we have to prepare data sheet, and add flange rating for flanges.
We select flange rating by comparing MAWP with allowable rating of flange.Whereas nozzle are applied to nozzle only
Now after code Interpretation BPV-VIII-1-16-85, is it mandatory to check all standard flanges against the nozzle loads? My main worry is do we need to mention in data sheet to project specification that vendor needs to check standard flanges against nozzle loads.

Regards,
manj

IMO, you can follow the code Interpretation BPV-VIII-1-16-85 together with code case 2901.
In practice, the problem of that interpretation was the missing formal method to perform such calculations. It is well known that applying the pressure equivalent method comparing with flange pressure rating is very conservative.

Case 2901 solved the problem and is reasonable. That's made the interpretation reasonable, too.