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Hello everyone, I’m dealing with a fire sprinkler system installed after 1984 that uses the sprinkler model shown below. I need to replace the sprinklers without changing the system’s overall characteristics. Unfortunately, I can’t find the original datasheet for this model. I can test the activation temperature and the K-factor, but I’m unsure whether this sprinkler is of the conventional type. Could anyone help me confirm if it’s a conventional sprinkler or provide any technical information about it? Thank you in advance for your help! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe 
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Are sprinklers required within an enclosed (conditioned) pedestrian walkway that connects two fully sprinklered buildings?
The walkway is 80 feet (25+ meters) wide and 26 feet (8 meters) above a roadway where vehicle loading and unloading may occur (temporarily parked vehicles are not considered storage). Is the walkway considered an exterior projection from each connecting building, and since it is an occupied space, will sprinklers be required under the walkway structure? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Forward flow testing for dry systems As an AHJ, this seems like a simple question, but I cannot find an answer.
We are diligent in enforcing the annual forward flow for wet systems. So, how do we verify the available water supply meets the hydraulic GPM requirements for dry systems? The annual dry trip test tells us only that water is available and the backflow device opens. We do have one occupancy that placed a shutoff valve ("slam valve") near the top of the riser. They close that valve for the annual test and trip the system, only allowing water in that small section of pipe where they also installed hose valves for the flow test with pitot readings. The valve is chained open normally. How do others measure GPM annually on dry systems to ensure it meets the designed system demand? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a church with a raised platform (wood construction) that is not accessible and is a concealed space. We typically have not provided sprinklers for this type of space. The AHJ is stating sprinklers are required per NFPA 13.
Are sprinklers required for a combustible, concealed space below a raised platform? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Good morning, I am in Florida and use the Florida Fire Prevention Code 8th Edition, which references NFPA 1 and 101 (2021), NFPA 72 (2019), NFPA 96 (2021), and NFPA 17A (2021).
I have a mixed occupancy strip mall that is fully sprinklered and has a fire alarm that was initially installed to monitor the sprinklers only. One tenant upgraded the panel to accommodate a full fire alarm for their unit. A different tenant, mercantile class C, in the strip mall has installed a hood and hood suppression system along with duct detectors for their upgraded AC system. The ducts serve only their unit and do not cross demising walls or serve other units. My interpretation is that the duct detectors and hood suppression systems must be tied into the building's fire alarm. Is this correct? Another question, would this tenant then need to upgrade their unit to include pulls and notification appliances? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Hello, I am trying to figure out what commodity classification vinyl doors are.
I am designing a fire sprinkler system for a warehouse that stores doors and windows with the main materials being wood, glass, and vinyl. Doing a google search vinyl doors are typically made out of PVC (polyvinyl chloride). NFPA 13 - 2019 - Table A.20.4(b) lists the following: PVC (polyvinyl chloride) products, up to 20 percent plasticizer - Class III PVC (polyvinyl chloride) products, greater than 20 percent plasticizer - Group A Nonexpanded Table A.20.4.3 Examples of Class III Commodities has Furniture; wood (doors, windows, cabinets, etc.); So I'm thinking the next question that I need to ask is how much plasticizer is used in vinyl doors? I'm thinking it is less than 20% and use Class III. Any thoughts? Thank you! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe How are we supposed to approach Fire Alarm requirement for elevator recall on key lock private elevator (elevators that goes directly into an apartment)?
I'm working on a new 3 story small apartment building where the first floor is only S-2 occupancy with no dwelling units and the 2nd and 3rd are R-2. Each floor classified as R-2 has 3 apartments and each one has a corresponding elevator that goes from the 1st floor and enter directly to each apartment. Access to each apartment is granted with a key that goes into the elevator. The building will have sprinklers likely NFPA 13 and will have smoke detectors with sounder base inside the dwelling units for notification. My question is how would you approach the elevator recall in this case taking into account that the only common area that the elevator land to on the whole building is the S-2 garage on the first floor? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I'm working with a not-so-good flow test on a project that will require a pump because of the flow test.
Where this is getting in the muck is the test flow rate being 712 gpm. The hydrant is about 565 feet from the entry and about 4 feet below finished floor elevation. This is a 5-story, light hazard with 2 standpipes, so the standpipe demand is 750 gpm. Flow test had 44 psi static and 34 psi residual with a 0.9 coefficient through the 2.5" outlet. As you know this is a 750 gpm system demand. The person over me is adamant that we not separate the sprinkler and standpipe systems out - sprinklers and then standpipe - by code when it comes to fire pumps. Even though this is a low-rise building and all we are technically concerned with is an automatic sprinkler system, and if the responding FD has an engine/pumper, the manual standpipe is in their realm. The argument is that they don't want a "partially automatic system" on any project; if a fire pump is to be provided for the project, they insist that the standpipe system connected to it must also be automatic. Back to the 750 gpm thing. At 34 psi, we have 712 gpm, obviously. The thing here is putting a 111 psi, 750 gpm pump on. They're concerned with the NPSH of the pump and not the duty point or the 150% rated test goals. (1) When a fire pump is provided to meet the needs of the sprinkler system, are the standpipes required to be automatic? (2) Is there a requirement here for automatic standpipes that I'm missing? The local jurisdiction has no amendments that affect standpipe requirements different than the model IBC. (3) Is an automatic standpipe here even achievable given the limits of the water supply, or are we causing more issues in testing down the road? If it was local, the FMs have already told me that's close enough and we will make up any flow from our trucks. What am I missing here? I understand clearly that at 20 psi the flow is 1,124 gpm. That's not what I'm trying to accomplish. I am attempting to make the combined system fully automatic per policy at 750 gpm and I'm told it's all good to go. Help a man at wit's end out here. TLDR: How would you approach manual vs. automatic standpipes when a fire pump is provided for a 5-story sprinkler system, but a 750 gpm pump could overtax the water supply? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Throughout my career, I have heard the term "turn the heads up for temporary protection during construction."
I've had bosses require uprights to be installed, and I've had bosses who just use the existing pendents and literally just turn the heads up. Which is correct? Would the length of construction determine it? How have others done this? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Does a panoramic or free-standing elevator have to be in a fire-rated shaft if it's not penetrating a floor assembly? IBC 3002.1 requires shaft enclosures per Sections 712 and 713 and opening protections for the shaft, but in this photo example of an elevator in an open atrium, I wouldn't think it's penetrating a floor slab, so it would be required to be in a shaft. I believe that the wall facing the floor would need to be rated accordingly, but not the rest of the shaft. I'm pretty sure this makes sense, but I don't see any code language that would explicitly say this is right. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  How does the main drain test differ from the hydrant flow test in analyzing a water supply?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Standpipe hydraulic placards - are they required? You don’t see too many of them, so it would be difficult to find out how much psi max to pump in I don’t see many at the FDCs. Some fire marshals ask for one, others do not. I feel I’m the only one providing them. NFPA 14 6.8 requires them and tells you what to put on them (2016 to present). I place them at the exterior FDCs, base of standpipes, at the tested valves, and at the fire pump. Why aren’t the signs enforced? Are you seeing these regularly? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  Does NFPA provide guidance on campus-style fire pump design?
Can I provide two water services (one from each building) and serve out to two buildings? NFPA 20 4.9 implies that campus-style designs are acceptable, but I am not seeing any code lines referencing any further requirements for such a design. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am working on an NFPA 13 hotel where the most demanding guest room is protected by 3 sprinklers: 1 sidewall (16x20) and 1 pendent (14x14) in the guest space, which totals 275 ft², and 1 pendent (14x14) in the bathroom. If the room meets all the requirements for the room design method, am I required to pick up a 4th sprinkler from the corridor? If not, then based on Section 19.4.1.3, would the sidewall sprinkler be allowed to use the listed flow, as the room area divided by 2 sprinklers would be less in this case? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  I am working in a warehouse with an existing ESFR system at the ceiling level. The new tenant is going to have manufacturing occupancies below, with no high-piled storage. We are utilizing the 2025 edition of NFPA 13.
There is a lot of ductwork being added to the spaces, and a question has come up regarding round and square ducts between 24 and 48" wide/diameter, and if protection is required below. For example, there is a series of (5) 42" Ø fabric ducts (Ductsox) running across a space. The top of the ductwork is approximately 6' below the deflectors of the 16.8K ESFR sprinklers overhead. When looking at section 14.2.10.3.4, I am interpreting the rules as follows - If a fixed obstruction is larger than 24" wide, and it isn't placed in accordance with table 14.2.10.2.1(a), it will require supplemental sprinklers regardless of the distance below the ESFR sprinklers. Obstructions over 48" will still always require supplemental sprinklers, and obstructions less than 24" won't need supplemental sprinklers if they can comply with one of the options 2-6 in 14.2.10.3.4. The confusion comes in with the reference to Table 14.2.10.2.1(a). Others in my office are interpreting the rules to mean that since the obstruction is greater than 31" below the deflectors, it would be acceptable to omit supplemental sprinklers underneath. I am of the belief that Table 14.2.10.2.1(a) doesn't apply at all since the obstruction is greater than 31" down from the deflectors - Since they don't comply with any of the other options in 14.2.10.3.4, supplemental sprinklers should be installed below obstructions between 24" and 48" wide when spaced more than 31" below the deflectors. What is your take on this? Are sprinklers required for obstructions between 24-48" wide when more than 31" below the deflectors? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When a new fire pump controller is installed or replaced, is an acceptance test required?
I suppose I know the answer, but I am looking for a code basis. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Assuming a jurisdiction requires sprinkler pipe to be bonded to the building grounding system, would a sprinkler system fed from a fire pump be considered bonded since it is attached to the pump which is already grounded?
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In sub-grade parking garages, with PRV fire hose valves/floor controls - for testing purposes, would you connect a PRV fire hose valve to the express drain via hose and pump vertically to get to the exterior grade to discharge? Are there any issues with this method during testing to consider? PRV floor control would be hard piped to the express drain and utilize the same pathway to the exterior. Then at the bottom of the express drain has a ball valve, acting as an auxiliary drain only. It can discharge to a gravity drain system, whether storm or sanitary, whatever your local AHJ permits. Or is everyone trying to discharge into a gravity drain at the bottom of the stairs and hoping to not flood anything? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  What is your method for determining whether to use a tree, looped, or gridded sprinkler system?
I would think that in most cases, a tree-shaped layout is sufficient, but I'm curious to your take as to why you'd choose otherwise. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Have 5 stories of parking with about 15 levels of residential floors above. For an enclosed, heated/conditioned garage we can use a wet system.
If we're using Extra Hazard Group 2 with high temp sprinklers or 11.2k sprinklers, which reduces our design area we know we need to account for "0.40 gpm/sqft x 2,000 sq.ft. = 800 gpm demand" at least. A PRV floor control valve like a 2-1/2" Zurn ZW5004 tops out at 500 gpm per the data sheet. Would it be possible to utilize two of these floor controls from different stairs and have an interconnected system on those levels? Or would it be better to utilize to try and separate the garage level sprinkler system from the standpipe for those levels and use a master pressure reducing valve station on ground level to feed the 5 garage levels? Would a redundant pressure reducing valve at a master pressure reducing valve station be necessary if the sprinkler feed is separated from the standpipe feed for those levels? Or could I just use a grooved 6" pilot-operated PRV like a Cla-Val 90G-21 (listed for 1763 gpm) before a floor control on garage levels? (a combined sprinkler/standpipe configuration) Lots to this, appreciate the feedback in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When calculating overhead systems with in-rack sprinklers, how much in-rack demand is added to the calculations?
I assume all in-racks within the most remote area, but want to ask to be sure I'm getting this right. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe As an AHJ, I would like to ask what other AHJ's enforce for sprinklers in R-3 Occupancies when home health or Boarding Care businesses open facilities in single-family homes?
Please explain your reasoning as well as thresholds like 5 or more, etc. We're evaluating what our requirements and/or enforcement should be. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe TL;DR:
How can surge/water hammer forces be managed in very tall high-rise fire protection system using a single high-pressure pump (~365 psi) without exceeding equipment ratings or NFPA limits? Question: Trying to pre-plan in my mind for some upcoming pretty tall highrises where design teams would like to utilize 1 pump in lieu of a high/low multi-pump set up. I'm coming up with a couple of challenges. For the sake of the problem lets assume the static pressure at the fire pump discharge flange is 365 psi. I'm concerned that fire pump starting methods might create shockwaves/water hammer in high-pressure standpipes whether it be at the start of the pump like across-the-line or end of the curve spike like a wye-delta closed might see. How concerning is creating surge forces that exceed coupling/PRV valve/Pressure Relief Valve listed ratings? First reaction for many like me has always been to utilize soft-start but electrically with generators soft-start has a much higher load that has to be accounted for in the generator sizing because of the electrical engineers have to size them as across-the-line because of the bypass & 600% FLA. Maybe they just have to suffer on their design for FPs to be what it needs to be, but am trying to be accommodating where it makes sense. Is the general method to rely on a main relief valve in these high-pressure systems? NFPA 14 limits us to 400 psi but I'm not finding pressure relief valves that are listed high enough for the static pressure of the system i.e. cal-val at 300 psi, Victaulic at 350 psi. Is anyone utilizing anything like an Amtrol Surge-Trol Tank type products? Maybe VFD controllers to flatten/lower the static pressure? Some additional concerns in my mind are PRV hose valves have a 400 psi rated value and some couplings for example Victaulic might be rated at 365 psi. I know there are higher rated couplings on the market, like 500 psi, but if my static pressure on the system is 365 psi, I could see a surge force exceeding the rated values (zero math to support that claim). I'm struggling to quantify the possible surge force values in the design phase and how to handle that. Reading SFPE Handbook of Fire Protection Engineering 5th edition Water Hammer section pg 1407, it's focused mostly on the closing of valves, and still wrapping my head around if those equations can be applicable/same for pump starting forces. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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