This inspection code covers the in-service inspection, repair, alteration, and rerating activities for pressure vessels and the pressure- relieving devices protecting these vessels. This inspection code applies to most refining and chemical process vessels that have been placed in service. This includes:

• vessels constructed in accordance with an applicable construction code
• vessels constructed without a construction code (non-code)-A vessel not fabricated to a ecognized construction code and meeting no known recognized standard
• vessels constructed and approved as jurisdictional special based upon jurisdiction acceptance of particular design, fabrication, inspection, testing, and installation.
• non-standard vessels-A vessel fabricated to a recognized construction code but has lost it's nameplate or stamping.