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I have a dry pipe system in which all test connections have an auxiliary drain except one. That one test connection is the farthest and highest connection, which is then piped down to ground level.
At ground level, the test valve is in a heated room and drains out through the wall. That pipe was filled with water (we don't know why) right to the top of the attic, froze, and burst an elbow. Should this test connection have had an auxiliary drain where the maintenance person checking for condensate and all other test connections likely would have found the filled test connection? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
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What is the NFPA Commodity Classification for fruit in plastic bins (for example, cherries, floor-stacked 20 ft. high)? The bins are open on top with holes for drainage and are full of cherries. Do the bins make this Class I a Class IV or Group A plastic instead?  Where are we with the newest clean agents?
I'm running into an interesting scenario where the discussion of the phasing out by 3M of the NOVEC 1230 agent is coming up. I mentioned the competitors to NOVEC 1230 that we're aware of - FK-5-1-12 but they are interested in the next-gen stuff because they don't want to have to redo anything in the near future. Does anyone have any experience with the Fluoro-K or any other newer, lesser used in the past but now have to look into agents? I'm aware of Victaulic's Vortex and CO₂ options, but I'm asking about chemical agents. I look forward to hearing your thoughts and experience. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can the Quick Response Reduction be used for an above-ceiling calculation for upright heads in an interstitial combustible space?
The combustible roof deck is approximately 13'-0 above the finish floor with a ceiling of 9'-0" below. Assuming the space from the roof deck to the ceiling is 4'-0", this allows a maximum 40% reduction. Or does the calculation need to go to the finished floor for a -3 x 13/2 + 55 for a 35.5% reduction? Which is correct? Is the ceiling, in this case, the floor with only 4'-0" elevation for applying the reduction in the interstitial space, allowing the full 40% reduction? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is the additional flow described by NFPA 13 27.2.4.2.5 (2019) based on the original minimum design area or the minimum area after modifications?
Say I have a light hazard system with low ceilings. The default minimum area is 1,500 sqft but is reduced to 900 per Section 19.3.3.2.3.1. The calculation on the sprinklers in that 900 sqft area results in 128 gpm total flow (not including the hose allowance). If the additional flow in 27.2.4.2.5 is based on the original 1,500 sqft, then I would need to add 22 gpm of extra flow on the main to get the minimum of 150 gpm running through the main. If the additional flow is based on the 900, then I'm already meeting the requirement of 90 gpm, and I can ignore the additional flow requirement. Similarly, we start at 1500 sqft in a dry attic system, but it needs to be increased to 2,535 sqft minimum due to the dry system and sloped ceiling. Will the minimum flow as per 27.2.4.2.5 be 150 gpm or 254 gpm? This sometimes comes up when using specialty attic sprinklers, which allow for fewer operating sprinklers in the calculation. It comes down to the definition of "minimum design area". Is this the original minimum area, or the modified minimum area? In my designs I've been defaulting to the larger of the two demands to be conservative, but what is the actual intent of this clause? I haven't found any discussions relating to the changing of the minimum design area. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA 13 is clear about a limit of 10 feet under a building before pipe needs to turn up and into a building (with exceptions for trenching).
What about pipe exposed within a basement? Is there a limit to how far an underground service can run exposed within the building before the system riser? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Has anyone ever used a slosh damper water tank on a roof as part of the fire reserve for the building?
The project is located in NYC. If so, are there any special requirements that need to be adhered to? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have an exterior elevator on a two-story building, required by ADA.
The required smoke detector outside the elevator door, installed under the soffit overhang, will quickly fill with dust/dirt. Any thoughts about using a heat detector at this spot that ties into the elevator recall requirement? I am the AHJ. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Best Practice suggests that a single FDC supply all fire sprinkler systems in a building, so no matter which FDC the fire department pumps into, all of the systems would be supplemented.
Is there a requirement in any code (except local, village, state amendments, etc.) that requires a fire department connection to connect to all systems? Or, can each system have its own FDC, provided it's properly labeled as to what system(s) are being pressurized by that particular FDC? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a requirement from a client to use K25.2 sprinklers on a building up to 50-ft in height.
The design criteria that is provided under NFPA 13 is 12 K25.2 sprinklers at 50 psi, but this criteria is not available in Chapter 13 of NFPA 13. Does anyone know where this came from, or whether it's appropriate? It's for up to a 50-ft roof for protection of cartoned, non-expanded Group A plastics. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a project for which someone else did the flow test for me. At the test hydrant, I have a static of 69 psi and a residual of 64 psi at an elevation of 238'. According to the information I was given at the flow hydrant, I have a static of 24 psi and a pitot of 25 psi at an elevation of 308'. With a coefficient of .90, they show a flow of 839 gpm. My question is - do you think it is acceptable to use a flow test showing a pitot reading higher than the static read at the same hydrant? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  Subject: Two story convenience opening separation from corridors. NFPA 101 (2021 edition) Section 8.6.9.1 permits convenience openings for two adjacent stories. But, these convenience openings shall be separated from corridors (requirement #3) and further states that separation should be by a smoke partition (requirement #5). How do you define a corridor versus an open floor area or lobby per NFPA 101, since no definitions are given within the code? Jurisdiction is required to follow NFPA 1 and NFPA 101. For example, a building has a large assembly space on the second floor. All doors from the assembly space lead to a ~40'-0" wide circulation space (+200'-0" long in the other direction). To reach the building exit stair, occupants from the assembly room must traverse the 40'-0" wide circulation space. Within this circulation space is a ~20'-0" x 40'-0" vertical opening that connects the 1st and 2nd floor. Should this circulation space be considered a corridor, and should the vertical opening be prohibited from being classified as a convenience opening without a smoke partition separating from the corridor? Or is the 2nd floor space to be considered an open floor area, with exits immediately accessible in different directions (NFPA 101 7.5.1.1.1) and not consider it a corridor? The width of the circulation space seems too wide to be defined as a corridor but NFPA only provides minimum width requirements for corridors, and no maximum width for a space to be considered a corridor as far as I can determine. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  If the fire sprinklers for an entire area or building have to be replaced, such as if they are more than 50 years old, is there any problem or benefit (hydraulically) from increasing the replacement sprinklers to the next higher K-factor (e.g., K5.6 to K8.0 or K8.0 to K11.2), especially for production and storage areas?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Forward Flow Test Confusion... I have an NFPA 13R system built in 2013 that doesn't have any hose connection(s) for forward flow testing. The sprinkler contractor is saying they're unable to conduct the test.
I am attempting to understand the codes around this topic and ran into several questions. First, NFPA 25: 2020 NFPA 25 13.7.2.3 states, "Where connections do not permit verification of the forward flow test at the minimum flow rate of system demand, tests shall be conducted at the maximum flow rate possible." Can someone please explain what this means exactly? My second question concerns using the main drain to conduct the forward flow test if it's sized appropriately. A previous Meyer Fire blog post, "Solutions for the Overlooked Forward Flow Test," Option 4, mentioned the 2016 NFPA 13 A8.16.2.4.2, but I cannot find that section in the 2019 version. Has this method changed somehow? Can the sprinkler contractor use the main drain as a means to conduct the forward flow test? If so, what else does the AHJ need to know? Calcs to prove drain size can flow system demand? Pitot reading? Thank you for reading and I'd love to find some clarity. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is there anything in the code that specifically talks about EV (Electric Vehicle) charging stations?
Anything that might say "If you are adding EV Stations in a garage the sprinkler system must be checked, upgraded or analyzed?" Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Our facility is exploring constructing two large (7,200 ft²) facilities for media blasting and coating large steel structures.
The facilities have a ceiling height of approximately 40' and are enclosed via a large roll-up door on one end. The coating systems are categorized as flammable liquids. There has been some internal debate on how to categorize these per the IFC - as "spray rooms," which would require fire suppression, or "spraying spaces," which the IFC does not have a prescriptive requirement for fire suppression. The commentary in the IFC notes that spraying spaces are typically "unenclosed", leading us to lean towards considering these spray rooms, even though they make up the entirety of the building versus a portion of it. We've reached out to some of the local AHJs, who all seem to agree with the spray room determination. However, the builder of the structures has indicated that most of their installations have not required suppression, even when reviewed by the local AHJ. Is categorizing these structures as "spray rooms" the wrong application of the term? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In NFPA 14, Sections 7.12.2.2(2) (2019) or 10.7.2.2(2) (2024) state that a "minimum of two FDCs shall be provided for each zone for the following: (1)* High-rise buildings (2) Buildings or multiple attached buildings exceeding 900 ft (274.3 m) perimeter distance." Neither edition defines "perimeter". Is it measured where the building meets grade? Should it account for all exterior walls? Two building which share similar "A" length and "B" width dimensions can produce vastly different "perimeters" depending how they're measured. (See image below.)  Thanks in advance.
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Over the weekend, an owner had a flooding incident due to a broken hose valve cap (the hose outlet valve was apparently in an open/partially open position).
The owner is requesting retrofit of 2½" hose outlet connections on their standpipes with valve tamper switches. Does anyone supply tamper switches for 2½" hose valves, or hose outlet valves with built-in tamper switches? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I'm working on an interesting scenario in which the client would like one main line into the building for fire and to tee off that line inside the building, with one line going to a giant indoor tank that holds 350,000 gallons.
It would be filled just one time per year. Assume 1,000 gpm for 6 hours that one time per year. First - do you all see this as a possibility right off the bat? We were talking about putting motorized valves wired back to FACP that shut off if the fire protection activates flow as a potential solution if it could work. Initially I asked about a water tank for that until I learned it was 350,000 gallons. Second - is it even possible to calculate out in that scenario? One thing I love about FPE is the unique, always challenging scenarios that come up regularly. I'm looking forward to figuring out how we're going to handle this facility. Thanks in advance for any input. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a residential project using NFPA 13 and are trying to determine whether the 8-residential sprinkler increase (or 3,000 sqft increase) applies.
Does this project require the sprinkler design below the ceiling using I-joists with sprinklers omitted from the concealed spaces, which are allowed under NFPA 13-2022 Section 9.2.1.6, if the I-joists defining the 160 ft³ compartments are not lined with a minimum 1/2" thick GWB adjacent to the web? The designer is using NFPA 13 Section 9.2.1.6 to omit sprinklers in the concealed space. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Before the Super Bowl on Sunday, it's time to celebrate our top players (ba dum chhhh). Thank you!
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