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
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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 I have a project with two existing 900 sqft apartments above a non-sprinklered marine repair garage. Only the apartments are required to be sprinklered.
Can I sprinkler the two apartments per NFPA 13D, or do I have to do per NFPA 13R? I know the definition of dwellings says no more than two dwelling units in 13D. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is it okay to design a fire protection system for a building using street pressure for the lower garage dry-pipe system, and using a fire pump for the upper floors when required?
If so, does NFPA 13 have a diagram for this? Also, how is the system piped to avoid starving the street pressure system when the fire pump engages? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In an area subject to freezing, we have a remote FDC that supplies a riser room at the same level. The feed is through underground pipe.
Is the base of the FDC required to have an automatic drain similar to what's at the base of dry barrel fire hydrants? If not, how are these FDC's typically drained after use? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a two floor building with a hydraulic elevator that is required to have sprinkler protection. Getting to the sprinkler in the pit from first floor is not possible.
My question is, can we feed the sprinkler in the pit from the second floor? Just pick a corner and pipe along the wall? The elevator inspector is telling us that our pipe can not run along the wall in the hoistway. How true is this? Is there circumstances where pipe can run up or down the hoistway, per code? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We are a large metropolitan area with multiple universities that have been operating for decades with high levels of hazardous materials. They want to have separated control areas, but their building construction does not meet current requirements.
On one side we can only enforce the code that these were built to, which was BOCA or even no building code at the time, but on the other hand, there is a reason why control areas came about in the first place. As they cannot easily upgrade the structure to meet 2-hr requirements, I am planning on just using equivalent level of safety through sprinkler protection and other factors, but was wondering if anyone had experience doing enforcement like this? Is NFPA 45 enforceable here? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a 119-gallon double-wall fuel tank for our diesel fire pump.
Our tank rep believes we only need (2) vents total: (1) an emergency vent for the interstitial space and (1) a combined normal/emergency vent for the primary tank. We have received pushback that we need (3) vents: (1) normal for the primary tank, (1) emergency for the primary tank, and (1) emergency for the interstitial space. We are having difficulties finding any requirements either allowing or not the combination of the emergency and normal vent lines of the primary tank (NFPA, building code, or UL 142). Do any of you know if the combination of these vents is typically allowed? What do you typically see for the venting of a diesel fire pump fuel tank? Note, this job does fall under 2022 California Building Code, but I am still interested in what is common even outside of California. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe If I have an in-rack system that needs to be calculated with the ceiling system, does the ceiling system need to be positioned above the most demanding racking? This might result in neither individual component area used being the most demanding of their type. Or do I calculate the most demanding rack along with the most demanding ceiling? I drew a quick-and-dirty sketch of a warehouse with the most demanding rack in red, the most demanding ceiling area in green, and the water source in blue. If the two areas are not lined up, this goes against the assumption that only one fire is happening in the building at a time. I'm thinking that the two need to be averaged over each other to come up with the most demanding single area, even if the most demanding ceiling or rack are not involved.
Thanks in advance for your input. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In reviewing the top articles from 2024, I re-read #11 regarding forward flow. As an AHJ, this is something we have been focusing on for the last four years and have uncovered multiple water supply issues.
My question is related to NFPA 13 and the 2-1/2” hose valve that is required for every 250 gpm (950 L/min) of system demand. From the fire suppression side, we usually generalize that a 2-1/2” hose valve can only flow 250 gpm. However, in our forward flow testing and research, we have found that a 2-1/2” hose valve off a main riser can actually flow almost 600 gpm. So my question to the forum technical design experts is, if we are getting an adequate gpm flow for system demand from the pitot reading, do we really need to flow a hose valve for every 250gpm of system demand? In other words, if system demand is 450 gpm and we are getting that from a single 2-1/2” hose valve, is that accurate and acceptable? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA references are based on current editions. While NFPA 101, Section 30.3.1.1.4 (New Apartments) allows vertical penetrations to be protected with a 1-hour rating when sprinklered, NFPA 101, Section 30.5.2 requires HVAC equipment to comply with NFPA 90A.
According to NFPA 90A, Sections 9.1.3 and 6.8.3, a higher level of protection is required for shafts that penetrate more than four floors (2-hr fire rated and fire dampers). Does the exception provided in NFPA 101 permit reducing the required fire rating to 1-hour for duct shafts, or does NFPA 90A take precedence? I'm curious to hear different perspectives on this. I can understand both sides of the issue but find it challenging to justify allowing a 1-hour fire rating for a vertical exit within a New Apartment while requiring a 2-hour fire rating for the duct shafts. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Keeping politics out of it, what most likely happened to the fire hydrants in Pacific Palisades, California?
Or looking at both possibilities, what likely happened if all water reservoirs were full and what likely happened if the reservoirs were empty or under repair? I presume 40 or 50 fire pumper trucks over-taxed a perfectly functioning water system to the point where supply tanks could not be replenished fast enough. Additionally is a California water reservoir a body of treated water that fills the underground piping system & storage tanks? Or, is a reservoir a body of water (near by) that is waiting to be treated, and then enter the distribution piping? Looking for a better understanding from those that might be more informed and knowledgeable on the subject here. Thanks. Moderator's note: Major cultural events have a tendency for discourse to go political quickly. This is a technical forum for technical discussion on topics relevant to the fire protection industry, and not a location for political discourse. We welcome and appreciate civil discourse that's informative and helpful. Please refrain from political commentary as it will be removed from this site. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What is an acceptable means to inspect/supervise underground fire line isolation valves in a "roadway box?"
These are non-indicating and unsupervised valves on a fire line. They do not have a lockable lid and may be in a drive or roadway, i.e. subject to traffic. If you recommend a seal, please be descriptive of how that would be practical. NFPA 13 provides the following applicable guidance: 16.9.3.3.1 Valves on connections to water supplies, sectional control and isolation valves, and other valves in supply pipes to sprinklers and other fixed water-based fire suppression systems shall be supervised by one of the following methods: (4) Valves located within fenced enclosures under the control of the owner, sealed in the open position, and inspected weekly as part of an approved procedure. Thanks for your help. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In NFPA 25-2017 Chapter 5 addresses "Loaded sprinklers." Of course, this has been a "LOADED" question for years and everybody's interruption of what that is whether or not NFPA gives a decent explanation of it.
My question is, we have a customer that we've performed a sprinkler test by removing an X amount of sprinklers and sending it away to a third party lab for testing which samples came back as a pass - but the question has come up asking if sprinklers remain to be loaded the same if not more over the years. What would be the timeline for re-testing? Would it follow the 10 year re-test? Or 5 Year sprinkler testing that NFPA 25 requires for sprinklers in "hazardous" environment areas? As this plant has over 600 sprinklers and getting up to them and cleaning them every year is not practical, that option is not on the table. See NFPA 25-2017 code for the discussion on it. Thanks for your take. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am a project manager currently building a SCIF in Northern Virginia. I was told by the landlord that we couldn't use Schedule 80 PVC for di-electric breaks as they have had a PVC break causing millions of dollars of damage prior. We don't like wrapping/grounding the pipe.
Have you run into this? Do options exist, and what would you recommend to isolate through a SCIF? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe From my AHJ perspective and in regards to flexible drops and tenant improvements, where you typically don't receive hydraulic calcs, how are you then accounting for their equivalent lengths and friction loss?
I know some AHJ's require new calcs whenever these are being used period. I'm interested to see how others handle this. Thank you! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am working on a sprinkler system where the corridor has a wooden ceiling, as shown below. Upright sprinklers protect the space above the ceiling.
I want to know whether the pendent sprinklers below the ceiling are also required? Is this an open grid ceiling under NFPA 13? The ceiling has the following characteristics: Bamboo ceiling panels with mesh void and solid wood frame with galvanized black metal rods as hangers for proper support, panels are to have a consistent panel size of 15 cm void between each panel and the wall and 30 cm void between the panels for the greenery to be hung. Can anyone help me in this case? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am hoping for some help here. I have a cold storage facility that has racks in it. Customer is adamant they do not want in-rack sprinklers. Building is 30-ft tall to the peak, storage is at 25-ft, racks are push back/drive in 29' deep with no longitudinal flue space. They are storing a Class I commodity.
Is there a ceiling-only design that's possible, for a dry system, for this? Or a direction for me to look into? It's not a conditioned space, just a big ice box. I would greatly appreciate any help or feed back, thanks. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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