scope:

Applicability.

This standard shall apply to fire and explosion prevention during cleaning and purging activities for new and existing flammable gas piping found in electric-generating plants and in industrial, institutional, and commercial applications.

Coverage of fuel gas piping systems shall extend from the point of delivery or source valve to the gas-consuming equipment isolation valve.

For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. [54:1.1.1.1(A)]

For undiluted LP-Gas systems, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators where no meter is installed. Where a meter is installed, the point of delivery shall be the outlet of the meter. [54:1.1.1.1(A)]

For facilities that produce flammable gas for consumption on site, the point of delivery or source valve shall be the discharge isolation valve for the gas-producing equipment.

Coverage of flammable gas piping systems other than fuel gas piping systems shall extend from the source valve serving the gas supply system to the gas-consuming equipment isolation valve.

Nonapplication of Standard.

This standard shall not apply to the following items:

(1)* Piping systems covered by NFPA 2

(2)* Piping systems covered by NFPA 51

(3) Fuel-dispensing facilities covered by NFPA 52

(4)* Piping systems covered by NFPA 54

(5)* Piping systems covered by NFPA 55

(6)* Piping systems covered by NFPA 58

(7)* LP-Gas (including refrigerated storage) at utility gas plants (see NFPA 59)

(8)* LNG facilities covered by NFPA 59A

(9)* Vehicle fuel dispensers

(10) Commissioning and maintenance of gas-consuming equipment

(11) Vent lines from pressure relief valves or devices unless such vent lines are also used for purging of flammable gas piping systems

(12)* Systems regulated by U.S. Department of Transportation (DOT) 49 CFR 100-199

(13)* Gathering lines from well pads to gas processing facilities

(14) Well pad piping systems