Codes and standards published by NFPA are displayed as read-only under license from NFPA solely for use within this system. NFPA material may not be downloaded, printed, reproduced, or transferred.

Charging or evacuating flammable gas piping systems can be a dangerous endeavor without proper safety protocols in place. NFPA 56: Standard for Fire and Explosion Prevention During Cleaning and Purging of Flammable Gas Piping Systems provides a valuable foundation for making safety-related decisions while developing procedures for these activities.

The 2014 NFPA 56 contains many key requirements for ensuring the development of safe procedures for cleaning and purging flammable gas piping systems, including:

• Identifying a safe discharge point
• Notifying and training personnel involved in such activities
• Preventing the development of a flammable gas mixture in occupied areas

The NFPA 56 framework can be adapted to almost any industrial environment where flammable gas is used. This edition has been updated to reflect some requirements where pressure relief valves and their associated piping are used to discharge gas during a cleaning or purging process. (In some plants, it is not possible to bypass the pressure relief devices during these steps.)