BS EN ISO 23251 applies to pressure-relieving and vapour-depressuring systems. Although intended for use primarily in oil refineries, it is also relevant to petrochemical facilities, gas plants, liquefied natural gas (LNG) facilities and oil and gas production facilities. The information provided is designed to aid in the selection of the system that is most appropriate for the risks and circumstances involved in various installations.
This International Standard specifies requirements and gives guidelines for examining the principal causes of overpressure. It also determines individual relieving rates and selecting and designing disposal systems. These include such component parts as piping, vessels, flares, and vent stacks. BS EN ISO 23251 does not apply to direct-fired steam boilers.
This standard has been amended to include implementation of ISO and CEN updates and the implementation of ISO corrigendum.