ASME BPVC Section VIII - Rules for Construction of Pressure Vessels Division 1: Design and Fabrication of Pressure Vessels provides requirements applicable to the design, fabrication, inspection, testing, and certification of pressure vessels operating at either internal or external pressures exceeding 15 psig. The vessels discussed in this Standard may be fired or unfired. This standard also contains appendices that provide further information on supplementary design criteria, nondestructive examination and inspection acceptance standards. Rules pertaining to the use of the U, UM and UV Code symbol stamps are also included.