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If a duct detector is installed, and the mechanical unit has a capacity of less than 2,000 CFM, it is required by code for the duct detector to be connected to the fire alarm panel?
Alternatively, removing the detectors can be considered in this situation. Looking for relevant code and standard basis. We're under the 2021 IFC, 2021 IBC, and 2019 NFPA 72. Thank you! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
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What NFPA Standard(s) apply for two diesel generator tanks?
Two diesel generators (not emergency or standby), outside (but have enclosures) with each diesel tank stored underneath, the tank is rectangular in shape and has ~5,000 gallons of diesel fuel. Looking at the following code path; IMC Chapter 13 for fuel oil piping and storage and IFC Chapter 6--> 605.4 Fuel Oil Storage Systems --> storage above ground in quantities exceeding 660 gallons --> NFPA 31; OR IMC Chapter 9 engine and gas turbine-powered equipment and appliances. Is this approach correct? In reviewing both NFPA 37 and NFPA 31, both seem to be applicable; however, when it comes to "outside aboveground tanks" of this capacity, they both reference NFPA 30 (Section 6.3.3 for NFPA 37 and 7.9.3 for NFPA 31). So here's the main question - is NFPA 30 applicable here? I base this on a few things: 1. NFPA 30 Scope section 1.1.2 item 9 - it says it is NOT applicable to "liquids in fuel tanks of... stationary engines" ; and 2. All the boundary and tank to tank separation requirements throughout chapter 22 are based on the diameter of the tank. This leads me to believe this standard was not written for the type of tanks I have, but instead typical giant circular storage tanks.? Any insight is greatly appreciated. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA 72 (2016) Section 17.7.5.3 says a duct smoke detector is required in the supply air duct; on the other hand, the IMC (2020) Section 606.2.1 says a duct smoke detector is required in the return air duct.
Which should I follow? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe If you have an open office area with (2) AHUs, each AHU supply fan provides 1,500 cfm of supply air and return air that is fully ducted and has no common plenum.
Would duct detectors be provided on the supply side of each AHU? Do you combine the "CFM" since both units serve the same area? If not, would you ever cumulatively add multiple units of CFM? This has been an ongoing question as each of our AHJs sees it differently. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Four-story office building wants to shut down five large air handlers nightly. Purpose is to lower energy costs when building is unoccupied. This will cause all fire/smoke dampers (FSDs) to close (the smoke detectors in return ducts need minimum operational air velocity).
The FSDs are mostly original from 1985-1988. Only UL tested for 5000 cycles and no dynamic. I cannot find a code reference to prohibit this and believe that the FSDs are already near the end of their functional lifespan. Many have been replaced due to bad actuators, binding jack shafts and missing blades. Anyone know of a code reference to prohibit this use or when a FSD must be replaced? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe [Moderator's note: since the first lithium battery question a few weeks ago, we've been flooded with more questions on the topic. We'll do our best to not overburden everyone here but still keep with the topics people are asking. As always, we're thankful for you all!]
Could anybody point out some publications that deal specifically with the ventilation of lithium-ion batteries during off-gassing and how the ventilation should be controlled? I am familiar with FM Global Loss Prevention Datasheet, and NFPA 855, and I went through some publications such as FIA, however from those I only get that there should be sufficient ventilation. I am more interested in the off-gas detection part of the design. The ventilation should be turned on and ESS turned off at the first sign of explosive gasses, but what gasses should those be? H2, CO, C2H4, CH4, or all mentioned in a combination? Not sure how to proceed in this. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For a smoke control stair pressurization system designed in accordance with IBC 909 and IMC 513, does the code require a duct smoke detector on the supply fan?
Does the installation of a smoke damper at the stairway boundary factor into this requirement? (i.e. IBC 717.3.3.2 requires a detector within 5 feet of a smoke damper). Normally this motorized smoke damper is closed and then automatically opens upon activation of a specific fire alarm signal. NFPA 92 6.4.6.2 does require a duct detector on the stair pressurization supply fan; however, I'm unaware of a similar requirement in IBC/IMC. NFPA's intent is to detect smoke on the air supply and shut down the unit before smoke compromises the stairway. For elevator hoistways that require smoke control, IBC 909.21.4.2 states to provide a detector. I would have expected a general statement in IBC 909.12 with the same intention as NFPA 92; however, I do not see a similar requirement in the IBC/IMC for stairways. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a project with a comment from the AHJ stating that the dryer vent cannot terminate to the exterior condominium wall, which is the egress wall for the condominium exit exterior breezeway on that floor.
We're under NFPA 101 (regarding Section 30-3.6.3 for Unprotected Openings). Is a duct penetration considered an unprotected opening? Dry vents cannot have fire/smoke dampers, so can it just be a metal duct? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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