Grounding Electrical Equipment to Underground Sprinkler Piping
The use of underground fire protection piping for electrical grounding increases the potential for stray ground currents and increased galvanic corrosion, which is why such use is prohibited by NFPA 24 Section 10.6.8. Grounding to piping systems that could have nonconductive piping or joints is especially dangerous, since it may not provide the expected ground. In no case should the underground piping be used as a grounding electrode for electrical systems. Electrical equipment should be grounded in accordance with NFPA 70®, National Electrical Code®.