National Electrical Installation Standards

Standards as High as Your Own

Thursday, August 16, 2018


I have a job at the NIH facility in Bethesda Maryland that I need to run a nitrogen line to a room being remodeled. We want to run the nitrogen line through an electrical room. The nitrogen line would run over several electrical panels. Can I run the nitrogen line over the electrical panels, Is this acceptable with the NEC codes? Nitrogen is non combustible in fact it takes the air away from a fire should a fire start in the electrical panel. I would appreciate your response to this question, Thanks for your time. If the nitrogen line can run in the electrical room code you please provide me with a code number.

Walt Ugolick



Hey Walt thanks for your question. The NEC does not specifically define electrical rooms or generally require them. Spaces about electrical equipment operating at 1000 volts and less is covered by 110.26. Switchboards, switchgear, panelboards, and motor control centers have dedicated space rules as stated in 110.26(E). The dedicated space is the depth and width of the equipment and extends to 6 feet above the equipment unless a structural ceiling is lower than the 6-foot dimension. If the "panels" in your example are actually panelboards then the nitrogen lines cannot be located in the dedicated space but could be located above the dedicated space if any space exists above the 6 ft dimension.

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