ANSI/API Standard 2000, Sixth edition, November 2009

ISO 28300:2008 (Identical), Petroleum, petrochemical and natural gas industries- Venting of atmospheric and low-pressure storage tanks.

This International Standard covers the normal and emergency vapor venting requirements for aboveground liquid petroleum or petroleum products storage tanks and aboveground and underground refrigerated storage tanks, designed for operation at pressures from full vacuum through 103,4 kPa (ga)[15 psig]. Discussed in this International Standard are the causes of overpressure and vacuum; determination of venting requirements; means of venting; selection, and installation of venting devices; and testing and marking of relief devices. This International Standard does not apply to external floating-roof tanks.