Natural Gas Generators
by Brad Keyes, CHSP, on Nov 11, 2020 12:00:34 AM
Q: In looking over NFPA 110, edition 2010, it does not make any distinction to the emergency generator prime mover being anything but diesel powered. Because of the equipment section in the Definitions identifies any equipment used in connection with the supply of emergency power is in fact part of the EPS. We have a natural-gas powered EPS. Is it required to perform in the same manner as diesel powered equipment and be tested and maintained in the same fashion per NFPA 110?
A: No, I believe section 220.127.116.11 of NFPA 110-2010 is the answer you’re looking for. It mentions spark-ignition generators are to be tested monthly with available load for 30-minutes or until the water temperatures become normal and the oil pressures stabilize. You are correct, though, in saying there are other sections of NFPA 110-2010 that specifically references diesel powered generators.
For your circumstances, you may ignore those sections that are specific to diesel powered generators, but all other sections would apply. This means you are exempt from having to do annual load bank tests if you do not meet the 30% rule, but you are required to conduct the 3-year 4-hour load test.