Definition(s)
Gas, protective
The gas used for pressurization or for the dilution of flammable gases to a level well below their lower explosive limit, usually below 25% LFL/LEL. The protective gas may be air, nitrogen, other nonflammable gas, or a mixture of such gases.
Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards
Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards