PD 5500
PD 5500 "Specification for unfired, fusion welded pressure vessels" is a code of practice that provides rules for the design, fabrication, and inspection of pressure vessels.
PD 5500 was formerly a widely used British Standard known as BS 5500, but was withdrawn from the list of British Standards because it was not harmonized with the Europeran Pressure Equipment Directive. In the United Kingdom it was replaced by EN 13445. It is currently published as a "Published Document" by the British Standards Institution.
