Hi there. I see your problem here. The lack of punctuation lends ambiguity to the language. I would expect a formal document like this to be more concise. From context, An assumption can be made though, and re-written thus, it becomes clearer: For category A and B oil tankers other than those constructed on or after 1 January 2017, check whether all cargo tanks constructed and utilized to carry oil are separated from the outer shell by a distance of not less than 0,76 m. I read PAME PART IIA: CHAPTER 1 – PREVENTION OF POLLUTION BY OIL. It seems clear that the context is all about oil tankers and their cargo carrying specifications.

Thank you，Benjamin, for answering my question so carefully and thoughtfully. Your answer is very clear and very helpful. I think I have got it.