_Ix
Member
- Location
- Denver, CO
Hey all,
The AHJ recently tagged us for an undersized fuel tank for a mid rise core/shell office building. The generator will be serving a fire pump and Article 701 loads.
I've reached out to peers in the industry, as well as my Cummins rep and none of them have had a problem with this before. I would like to see if anyone else has had experience in this matter.
The AHJ is citing NFPA 110 - 5.5.3: "The main fuel tanks shall have a minimum capacity of at least 133 percent of either the low-fuel sensor quantity specified in 5.5.2 or that specified in Table 4.1(a)."
Referring to Table 4.1 appears to indicate that the generator needs to run for 8 hours as indicated by NFPA 20 - 9.6.2.3: "The generator fuel supply capacity shall be sufficient to provide 8 hours of fire pump operation at 100 percent of the rated pump capacity in addition to the supply required for other demands."
Basically, the minimum tank size for any generator serving a fire pump is going to be 8 hours X 133% = 10.64 hours. This far exceeds the NEC's minimum run time of 2 hours. My gut feeling is that this seems excessive and perhaps there is some code misinterpretation, but I wanted to see if anyone else has experience dealing with this.
Thanks.
The AHJ recently tagged us for an undersized fuel tank for a mid rise core/shell office building. The generator will be serving a fire pump and Article 701 loads.
I've reached out to peers in the industry, as well as my Cummins rep and none of them have had a problem with this before. I would like to see if anyone else has had experience in this matter.
The AHJ is citing NFPA 110 - 5.5.3: "The main fuel tanks shall have a minimum capacity of at least 133 percent of either the low-fuel sensor quantity specified in 5.5.2 or that specified in Table 4.1(a)."
Referring to Table 4.1 appears to indicate that the generator needs to run for 8 hours as indicated by NFPA 20 - 9.6.2.3: "The generator fuel supply capacity shall be sufficient to provide 8 hours of fire pump operation at 100 percent of the rated pump capacity in addition to the supply required for other demands."
Basically, the minimum tank size for any generator serving a fire pump is going to be 8 hours X 133% = 10.64 hours. This far exceeds the NEC's minimum run time of 2 hours. My gut feeling is that this seems excessive and perhaps there is some code misinterpretation, but I wanted to see if anyone else has experience dealing with this.
Thanks.