First of all, try the American Petroleum Institute for their guidelines, recommended practices, and reports. There are plenty and the industry uses them.
Several standards to be familiar with: API 510, API 570, API 579, and API 653. All deal with inspection of equipment and all have training/certification available. Take a look at the API catalog under "Inspection of Refinery Equipment", which starts on page 51, I think. There you will find a lot of documents referring to inspection.
The next item is to look up the ASME Boiler Codes and Piping Codes.
And, if you don't have trained/certified personnel, training and certification is VERY important to having a properly staffed inspection group. So, you will need to look into that.
There are probably other standards I have left out, but those are the basics. There is a book: "The Petroleum Refinery Engineer's Handbook" by JF Strachan (Philosphical Library, New York) (1956) that gives some basic philosophy on setting up a department. But, there may be some newer books that do the topic much better. (I know that some of the things discussed are really outdated.)
Whew! I don't envy you having to set all this up. There is much more involved than what I describe here. Just one question: Have you ever thought about contracting this work out?
Enjoy!
