With the absence of an OSHA Flammable Gas standard I have been using NFPA 58 since 1994 and it is one of my all time favorite RAGAGEPs. I am always pushing clients to use it for their flammable gases, as well as the IFC Chapter 58, especially when their flammable gases are stored/processes/handled as a Liquidfied Pressurized Gas. This 2020 Edition has some nice revisions and upgrades to consider…
- fire resistance ratings
- schedule 10 steel piping has been allowed for use in aboveground vapor service only (SAFTENG NOTE: no way in H_LL I would promote this)
- austenitic stainless steel has been allowed as a piping material
- fire extinguishers are NOW PROHIBITED LP-Gas pressure fires unless the source of fuel can be shut off promptly
- inspection of the face seal on CGA 791 and CGA 793 connections prior to filling
- new piping purge requirements/procedures, and others.
In the 2020 edition, new requirements for fire resistance rating and noncombustible materials have been added to specify when materials are required to have a certain fire resistance rating or when they must be noncombustible. Schedule 10 steel piping has been allowed for use in aboveground vapor service only and austenitic stainless steel has been allowed as a piping material.
Fire extinguisher requirements have been revised to specify that fire extinguishers shall not be used for LP-Gas pressure fires unless the source of fuel can be shut off promptly, a revision that removes conflict between industry standards and this code when choosing a fire extinguisher for an application.
Requirements have been added to require inspection of the face seal on CGA 791 and CGA 793 connections prior to filling because defects in the connection face seal will degrade the effectiveness of the seal; if any defects are found on the face seal, the cylinder is not to be refilled and the valve is to be replaced.
Purging of piping within the scope of NFPA 58 has been revised in the 2020 edition to direct the user to the purging procedures of NFPA 54, regardless of the system’s operating pressure. In previous editions, NFPA 56 had been referenced for purging procedures; however, LP-Gas systems under the scope of NFPA 58 are excluded from consideration in NFPA 56. While NFPA 54’s scope only covers LP-gas systems up to 125 psig (0.86 MPag), the purging procedures in NFPA 54 are also appropriate for NFPA 58 applications.
Revisions were made to Chapter 15, Operations and Maintenance, to specifically reference operations and maintenance requirements and to remove a number of unrelated installation requirements. Additionally, the scope of Chapter 15 has been revised to exclude systems regulated by the U.S. Department of Transportation because its requirements for operations and maintenance are more stringent.