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Under NFPA 13, how far away should an intermediate temperature sprinkler be from a two-bulb, 500-watt bathroom heat lamp?
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In a 3-story building with 3 standpipes, one of which is a combination standpipe/riser, and the standpipes are manual wet, with 50 psi.
On a 5-year test, how do I flow 1000 gpm (no pump) at 100 psi? Do I involve the fire department? The old hydraulic plates showed 70-50 at 260 flow. Three years later, they are showing 50-40 at 320 flow. So I cannot pass this, even though the water supply has diminished. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We are completing a buildout for a spec suite; the shell warehouse building was just constructed and has a fire sprinkler supervising panel.
The fire department is saying we have to tie the duct detector into the fire alarm panel. This building does not have fire alarm, only sprinkler monitoring. Are they correct in saying we have to tie in the duct detector? Thank you! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a contract that calls for concealed, extended coverage horizontal sidewalls in an area with a Turf Switchblade Acoustic Ceiling. The issue I'm running into is that the Tyco RFIII EC HSW has a maximum distance below the ceiling of 12", and the acoustic has a maximum dimension of 9.4" down from the ceiling.
Therefore, I won't have the 4" minimum distance between the deflector and the obstruction. Has anyone else encountered this type of issue? Has anyone found a concealed sidewall extended coverage that can be 18" below the ceiling? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe According to NFPA 20, for any pump installation, the NPSH supplied must be at least equal to the NPSH required for the operating conditions specified.
So does the NPSHₐ need to be continuously maintained at or above the NPSHᵣ during pump operation? During the operation of the fire pump, the liquid level of the fire water tank will keep dropping, which may lead to a situation where the NPSHₐ is lower than the NPSHᵣ (unless the fire water tank is built at a very high elevation). Is this situation permitted? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We are designing a project that has a porch area (approximately 88-ft long x 23-ft deep) at grade with occupied enclosed building space above it (the building overhangs the porch by 23-ft).
To avoid a costly dry-pipe system for this area, the CM is looking to serve this area from dry sidewalls connected to the buildings automatic wet sprinkler system. Is anyone aware of any dry sidewall heads (exposed or concealed) for this application that can throw 23-ft? The building will have a fire pump so the extra pressure would not be an issue. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am modeling the elevator pressurization system in CONTAM to demonstrate compliance with SBC 201 (IBC-based) requirements.
Normally, we use simplified spreadsheets, but code enforcement now requires performance verification through simulation. In a model where the elevator shaft is adjacent to a protected service lobby, shell and core area, and a loading bay, is it sufficient to demonstrate pressure differentials only along the egress path (shaft → lobby → stair), or should other adjacent but enclosed spaces also be included? What method do you recommend for extracting and presenting results—direct export from simulation (as in ASHRAE Applications, Fig. 21 Ch. 54) or summarized plots similar to Fig. 11.13 in the Handbook of Smoke Control Engineering, 2nd Ed.? Lastly, when modeling the shaft, should it be defined as a flow path with cross-sectional area and perimeter replicated across all floors, except the top floor? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For scissor stairs having 2 separate standpipe risers (one of them is a combined sprinkler and standpipe system) running 12 floors, how do we size the pump flow rate required?
Can we argue that we can use a 500GPM pump since the Risers are in close proximity to each other and are within one stairwell, or should we use a 750GPM pump following the NFPA 14 sizing of 500GPM plus 250 GPM per additional riser? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Could anyone point me to statistics to show how likely a single interlock pre-action sprinkler system is to spuriously or falsely activate?
A client is concerned about possible water damage in a high-voltage switchroom that could damage their gear and cause a lengthy business interruption. I have tried examining NFIRS data, but its format makes it difficult to analyze without a background in relational databases. I would like to explain the relative risk to the client in terms of 'it's a 1 in 100,000-year event you are concerned about' or whatever the stats point to. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe How do you coordinate what dialing out method with the client/telecom group, etc.?
A new fire alarm system, let's say a college building, for example, what do you typically see? Does the college have its own monitoring station? Do you dial out signals via cellular or internet, or both? Do dial-out signals go to both the college monitoring station (say, a life safety office) and a central monitoring station? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can someone explain NFPA 13 20.5.3.1.3 for Multiple Row Racks?
Unless the requirements of 20.5.3.1.3.1 or 20.5.3.1.3.2 are met, multiple-row racks without solid shelves shall be considered racks with solid shelves. Section 20.5.3.1.3.1 Multiple-row racks without solid shelves shall be considered open racks where both transverse and longitudinal flue spaces are provided at maximum 5 ft (1.5 m) intervals. 20.5.3.1.3.2 Multiple-row racks without solid shelves shall be considered open racks where transverse flue spaces are provided at maximum 5 ft (1.5 m) intervals and the rack depth does not exceed 20 ft (6.1 m) between aisles that are a minimum width of 3.5 ft (1.1 m). Does this mean you have to have a 6-inch flue space on all 4 sides of each pallet load every 5ft within the rack, OR a 6-inch transverse flue space every 5ft, but the rack cannot be deeper than 20ft? Is it one or the other, and do you see one more often than the other? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a quick question about estimating the pressure requirements for an automatic wet sprinkler system during the initial design phase.
Qm = d X (Area per Sprinkler) = (0.15) X (130sqft) = 19.5 gpm Estimated Total Flow (ETF) = Qm X N X F plus hose demand = (19.5 gpm) X (12 sprinklers) X (1.30 for spray pattern overage) + 250 gpm (Outside Hose Stream) = 554.2 gpm Minimum pressure needed for the system. = (19.5gpm/5.6K) = 12.13 psi for the most demanding sprinkler + another 20-35 psi for potential friction loss throughout the reference. The total estimated pressure needed would be 47.13 psi, not factoring in elevation change. The 20-35 psi for potential friction loss is an engineering judgement based on experience. What is the recommended potential friction loss for an initial design phase, and where would it be referenced at? I need to reference the source of recommended potential friction loss for the project. SFPE, NFPA or etc? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Question in relation to ESFR sprinklers. Per NFPA 13 2016 Section 8.12.5 - obstructions 12" to 24" wide, the sprinkler must be 2 feet away.
There is no specific code for obstructions larger than 24"; does this mean these obstructions would always require coverage beneath? I ask because I have a 36" cable tray - if it's centered between two branch lines, can I apply the code to half the obstruction? In this case, the head would be further than 2' from 18" of the obstruction on both sides. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a project where there are small bumpouts on either side of a room that are sized just big enough to store an accordion ceiling partition when not in use. The partition divides a bigger classroom into two smaller classrooms when used.
Do I need to somehow have sprinkler coverage in the bumpouts? The small areas are only exposed when the partition is deployed, which results in two even smaller spaces on each side of the partition. NFPA 13 Section 9.2.9.1 seems like one possible code section to allow an omission. What are your thoughts on this allowance? Seems challenging to incorporate sprinkler protection in those small areas and not very practical for the low fire hazard they present. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In an automated warehouse, is it feasible to replace the in-rack sprinklers with ceiling sprinklers on the upper racking levels?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a project involving an outdoor dust collector. My firm specified a dry-pipe sprinkler system for it.
The contractor asked if an antifreeze loop would be acceptable as a substitute, and we said no, as the AHJ does not want to deal with the maintenance side of an antifreeze loop long term. The contractor states that the head connection in the collector is pendent instead of upright, and they can't go with the dry system because of trapped water concerns. I think a dry pendant sprinkler would work as it's allowed (even required if an upright is not used) by FM Data Sheet 2.0. Anyone install a dry pendent in a dust collector, and have any drainage issues or had to add a drum drip or other means of drainage to make the system work long term? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a hotel building that requires a standpipe in each of the two staircases. One of the stair shafts has a door to the outside at grade level, but there is no door to the first level inside. The lowest level with an interior door is the second floor, which has its own hose connection.
It doesn't make sense to provide a hose connection at the ground floor, but is there a code basis to support this? Thanks! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Thanks for fueling a stronger community this season! Here are the top contributors for October!
Does anyone have experience with bench testing pressure-reducing FHV's?
We have horizontal corridors in a hospital, and having a fire hose and flow noise/water in certain areas is not an option. NFPA 25 2020 Edition, A.13.5.2.2 allows bench testing (i.e. remove the FHV, take it outside to conduct the 5-year test). Has anyone performed this? What is the procedure, and did the AHJ find it acceptable? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Good morning, I'm designing sprinklers for a Class III warehouse. The warehouse has a ridge vent that's currently enclosed on the side walls.
What ceiling height should be considered for the design: the average ceiling height or the height of the center of the ridge vent? The lower part of the ridge vent is 39.66 ft, and the upper part is 41.5 ft. If I consider 39.6 ft as the height, I could work with a 25.2 kPa sprinkler at 25 psi, but if I consider 41.5 ft, I should consider a pressure of 40 psi, and the fire pump would change. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe My coworker and I are disagreeing about townhomes.
Can each townhouse (3 total) have its own NFPA 13D system? Or do they need to have one total system? Each townhouse has a 1-hr separation in the form of UL U347. I cannot find anything that says they can't each have their own, but he is saying he can't find anything to say they can, to which I have always said if it doesn't say no, then it's usually allowed. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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