According to NFPA standards, where should the purging of piping systems primarily occur?

The purging of piping systems should primarily occur outdoors to ensure safety and compliance with NFPA standards. When purging, combustible gases are expelled, which poses a risk if done in enclosed spaces where they could accumulate and create a hazardous environment. Outdoor purging allows any released gas to safely dissipate into the atmosphere, reducing the risk of ignition and ensuring that any flammable vapors do not build up in confined areas. This practice aligns with safety protocols designed to protect personnel and property from potential hazards associated with gas buildup.

In contrast, purging indoors or in confined spaces can increase the risk of explosive atmospheres. While specialized testing facilities and venting chambers might provide controlled conditions, they are not the primary locations specified for the purging process according to NFPA guidelines.