I'm in a bit of a grousy mood this morning, so bear with me. The last time the acronym "BWR" was used, it meant "Benedict-Webb-Rubin." I think you mean "boiling water reactor..." Because there are so many engineers from so many different disciplines, it's always best to spell out acronyms.
Ok, rant over.
I'm not a Code expert, but I believe the answer is "it depends." Many nuclear plants in the US were not built to ASME Section III (because it didn't exist at the time.)
You will probably get a much more definitive answer if you post on forum292 or even forum794. If you do decide to post on another forum, either red-flag this post to delete it or provide a cross-reference to the other thread so that people realize it's cross-posted.
Patricia Lougheed
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