Definition(s)
Rated Relieving Capacity
Relieving capacity used as the basis for the application of a pressure-relief device, determined in accordance with the pressure-design code or regulation and supplied by the manufacturer. NOTE The capacity marked on the device is the rated capacity on steam, air, gas or water as required by the applicable code.
Source: API STD 521, Pressure-relieving and Depressuring Systems, Fifth Edition, January 2007 (Addendum May 2008). Global Standards
Rated Relieving Capacity
Flow capacity of a relief device expressed in terms of air flow at standard or normal conditions at a designated pressure or vacuum. NOTE Rated relieving capacity is expressed in SCFH or Nm3/h.
Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global Standards