All ASME Code vessels are inspected by an approved Code inspector. The manufacturer will supply Code papers signed by the inspector. The nameplate on the vessel will be stamped to signify it has met the requirements of the Code. One of these requirements is that the vessel was tested to 1.5 times MAWP. However, this is only one of the requirements. The mere fact that a vessel is tested to 1.5 times MAWP does not signify that it has met all the design and quality assurance safety aspects of the Code.
It must be pointed out that a Code stamp does not necessarily mean that the vessel is fabricated in accordance with critical nozzle dimensions or internal devices as required by the process. The Code inspector is only interested in those aspects that relate to the pressure-handling integrity of the vessel. The owner must do his own inspection to assure that nozzle locations are within tolerance, vessel internals are installed as designed, coatings are applied properly, etc.