What is NFPA's policy/code on refueling mission critical portable diesel generators while engine is running?
NFPA 30, Flammable and Combustible Liquids Code has some requirements:
2018 NFPA 37 has some requirements that may applicable. You may have to a closed piping system to refuel the tank while the engine is running. There is much more information in this standard for installing closed piping system.
NFPA 37 does not apply to portable engines. The generator should be shut down and allowed to cool down before being refueled.
NFPA 37 applies to portable engines that remain connected for use in the same location for a period of one week or more per Section 1.3.1 of the standard. This applies to engines on generators.
A closed pipe system for refueling the tank is a consideration for fueling the engine while its running.
I misspoke on NFPA 37. Read the manufacturer's operation instructions on how to refuel the generator. The following is from the operational manual from a manufacturer of diesel trailer mounted generators.
DO NOT fill fuel tank near an open flame, while smoking, or while engine is running. DO NOT fill tank in an enclosed area with poor ventilation.
I concur with you.
I agree that NFPA 37 applies to portable engines that remain connected for use in the same location for a period of one week or more per Section 1.3.1 of the standard. This applies to engines on generators.
But I am not sure for the portable generator.
If you were to use a portable generator as power source whenever a Level 1 or 2 EPSS is out of order, the requirements of NFPA 110, Standard for Emergency and Standby Power Systems concerning fuel systems. 2016 NFPA 110: 126.96.36.199 refers to NFPA 37 for fuel tanks and systems.
To keep the generator operational at all times without power shutdown and cool off, the fuel system is to comply with NFPA 37. I see closed pipe fuel system allowed by NFPA 37 may be a viable solution. Or running another portable generator wired so one could be shut down and cooled off for refueling.
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