A Restrictive Flow Orifice (RFO) is a type of orifice plate. They are used to limit the potential danger of an uncontrolled flow from, for example, a compressed gas cylinder by:
- limiting the accidental release of a hazardous gas (flammable, toxic, etc.) resulting from regulator or other component failure,
- restricting flow in a system in order to assure adequate pressure relief valve sizing and system over pressure protection, or
- restricting flow from bulk sources