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I'm working with a city inspector who is adamant that we add a second non-rising stem valve (NRS) in the fire sprinkler service main just before the building. The first valve being in the street at the live-tap location with the roadway box.
Is a valve required on the service main before the building? The requested location would place the valve under the sidewalk, accessible by T-handle wrench only, prohibiting reliable supervision of any kind. I can't seem to find any language in NFPA 24 that I can use to argue against the second unsupervised valve. I don't see any value in the position the inspector has taken and requested a copy of the city ordinance requiring the additional valve. Installing the second valve wouldn't be a huge deal but certainly seems like an unnecessary opportunity for an unsupervised valve to get closed or fail. I would like to hear what others in this community think and if anyone has something to offer. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
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Has anyone designed a dry manual standpipe for a pier or dock standpipe system in the past?
My question is in regards to materials used for the pipe. With the tides rising and falling my client is struggling to find an approved material that will allow for enough flexibility. I walked an adjacent marina to our project and it looked like they used 4" heavy-duty rubber tubing to run out the standpipe lines and transitioned to steel only for the vertical 2 1/2" up to the hose valves on the dock. Any information to point us in the right direction would be helpful. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What does "listed for fire protection use" actually mean?
The Department of Defense specifications Section 21 13 13 calls for backflow preventers to be "listed for fire protection use". From what I have found, there is no such specific listing. Has anyone else heard of this? Thank you for your input. Hi everyone - thanks for answering my previous questions and for checking out today's as well.
I have three projects all connected to the same central fire pump assembly. It's a huge network of pipe running for miles. The client is having a problem with the fluctuating pressure (up and down) on the network for some reason that affects the fire pump's suction pressure. It's in series, and connected to each project. The client refuses to add a break tank and cut the fluctuation. In your experience, is there any alternative solution available? Would a pressure relief valve help? What would happen when the pressure is less than design? Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In regards to installing pressure reducing stations for separating areas of the building into different pressure zones, NFPA 14 calls out that the FDC needs to be installed downstream of the pressure reducing valves.
Is a separate FDC required for each pressure zone? If you provide just one FDC, and the fire department supplies the system for an upper floor of a high-rise, you will exceed the maximum working pressure of the lower systems. I'm not sure how that's possible to avoid. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can the pipe from a remote FDC at the front of our building route under the building slab to connect to our fire pump room at the back of the building? The Fire Pump Room is on the basement level. This is for a six-story hotel with a partial basement along the back portion of the building that is open to a lower grade level in back. Here's a sketch below.  The fire marshal requires a remote FDC at the sidewalk in front of the building. Our fire pump room happens to be on the opposite side, in the back.
The most straightforward routing is below the building, but it is minimum 60' of run which certainly exceeds the 10' maximum distance allowed for the fire supply from NFPA 13. Going above the first floor ceiling is challenging given all the interiors/ceilings, public spaces, and glass at the street front. Given that the FDC pipe is normally-dry and not pressurized, do we have the same restrictions of 10' max below grade? Even if not, can't say I'm thrilled about having that many joints below our building above. Thanks for your help/thoughts! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Do open (exterior) stairs need standpipes?
If the stairs are more than 50% open, sprinkler protection is not required but what about standpipes? This building has three stairways. Two are interior and one is open and on the exterior. Standpipes are provided in the two interior stairways. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a plan reviewer that is not accepting our proposed design for a manual standpipe calculation.
The calculation shows a required pressure on the fire department pumper truck to be a minimum of 217 PSI. It has been confirmed that the pumper truck can reach and/or exceed 250 PSI. The AHJ is requesting that we increase the standpipe from 4-inch to 6-inch, which is not alleviating the higher pressures as we are still above 175 PSI. This would be a first for me to have to install pressure reducing hose valves on a manual wet standpipe. My understanding per NFPA-14 (2016) 7.2.3.2 is that this is only an issue when the static pressures on the systems exceed 175 PSI (city static is 113 PSI). So in essence, we are advising the fire department pumper truck operator to dial his pump up to 217, but this wouldn't be static, as they would be flowing out of the hose valve(s), correct? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We are working on a new (750 gpm) standpipe system.
When testing and setting the field adjustable 2-1/2" PRV hose valves, do you set each one flowing 250 gpm while also flowing 500 gpm elsewhere, to account for the hydraulically calculated design (i.e. lower inlet pressure per NFPA 14-11.5.5.1)? Or do you just set each one only flowing 250 GPM by itself? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a highrise that exceeds 400-ft in height. The engineer designed a combination riser with all of the floor control assemblies coming from one riser, and not alternating as is in code.
I'm wondering if there's something I'm missing - any way around alternating the floor control assemblies, like upper-level pumps being considered separate systems or something of the like? Looking for better understanding here and being sure I'm not missing something bigger picture. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA-14 2019 Edition. There is a new section in NFPA 14 - Section 7.8.1.2.1:
The pressure required at the fire department connection for manual standpipes shall not exceed the working pressure of the system components of the standpipe system or sprinkler system when the system is a combined system. Does anyone have any idea why this was added? It seems to me that the maximum pressure at the FDC would be 175psi as this is what the sprinklers are rated. Pumping at that pressure I would never get the 100psi required at the top of the most remote riser. Or am I interpreting this section incorrectly? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Hi All, Is there a code reference on the maximum amount of time allowed to close a wall PIV (or any valve for that matter)?
I have a Wall PIV that is hard and slow to turn, and takes about 30 minutes of fighting to fully close. Servicing of accessible components has not helped. I probably won't be able to get funds to repair/replace unless I can quote a code violation. I have only found a minimum amount of time, but nothing for a maximum. Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is there support in the standard to require a control valve supplying a combination sprinkler/standpipe system (standpipe isolation valve) so that a ladder wouldn't be needed to close the valve?
All control valves are to be accessible, but not necessarily readily accessible. I like to require that they not be installed more than 7-ft, but am looking for code guidance here. Is there code justification for 7-ft valve requirement? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am reviewing a set of fire suppression drawings from another engineer that is working as a sub to the sprinkler contractor. We created an outline of the fire suppression requirements (a performance spec) and then the contractor hired another engineer to finish the design. The building is a 6-story wood frame residential project. There are two exit stairs each with a Class I Standpipe and 2.5-inch fire hose connection (FHC). The building is an 'L' shape and the total travel distance from one FHC to the other is approximately 300-ft (91m). There is a 2-hour fire-resistance-rated wall part way along the corridor (124-ft from one FHC, 174-ft from the other). The contractor's engineer is calling for an additional third standpipe next to the 2-hour rated wall - is this required or not? I'm not sure how to interpret Sections 7.3.2.3 and 7.3.2.3.1 of NFPA-14. The project is in BC, Canada; and we're using NFPA-14 (2013 Edition). I have attached a markup of a typical floor plan.  Thanks in advance!
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We're designing a Wet Manual Class I standpipe in a low-rise building with 4 stairs/standpipes and therefore 4 isolation valves. There are 7 total levels of this building.
The horizontal supply pipe must be located in the level 5 ceiling. Is it allowable to locate the standpipe isolation valves at this 5th level versus the more typical location near the bottom of each standpipe? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe According to the International Building Code Section 905.3 (2018 Edition), a standpipe is required in any building with four or more stories.
We have a small building (three family homes) but the first floor is all a parking garage, and then 3 more floors over the parking garage (one home per floor). According to the IBC, do we still need a standpipe even if it's such a small building? If we do need a standpipe, does the service have to be 4-inches or can we have it at 2-inches and increase the riser up to 4-inches to feed the manual wet standpipe? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a series of highrise buildings where an NFPA 13 sprinkler system and a wet standpipe system (NFPA 14) are to be installed.
If the sprinkler and the standpipe systems are supplied by a common fire pump, and horizontal supply pipe, but have separate vertical risers, will the system be considered a combined system? Will the subsection of NFPA 14 (2019 Edition) section 7.10.1.3.1.1 apply? 7.10.1.3.1.1 In a building protected in accordance with NFPA 13 or NFPA 13R, the water supply for the combined sprinkler and automatic standpipe system shall be based on the sprinkler system demand (including any hose stream demand) or the standpipe demand, whichever is greater. The buildings are fully-sprinklered, and the proposed fire pump is rated at 1,000 gpm. There is a water storage tank of 30,000 gallons. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a hospital that has two "double hose valves" at the top of two different standpipes on the roof. One is on a helipad and the other is below on a different roof. Both are the most remote locations.
Per NFPA 25, for the 5-year test, I'm supposed to flow 500 gpm at the most remote then an additional 250 gpm at a different standpipe until I reach 1,000 gpm for the fully-sprinklered building. Can I just flow 500 gpm out of both double-hose valves (2 standpipes), or do I have to flow 500 gpm, then 250 gpm, then 250 gpm using three different standpipes? Thanks. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Do any of your projects with dry manual standpipes hold supervisory air?
I understand NFPA 14 Section 6.1.1 to have a requirement for supervision of the standpipe system: 6.1.1 Location of Dry Standpipes. Dry standpipes shall be monitored in accordance with NFPA 72 with supervisory air pressure. Are all dry manual standpipe systems provided with supervisory air? Or is this section meant to pertain only to automatic or semi-automatic dry systems? I don't think holding supervisory air under pressure in a dry manual standpipe is feasible, being that there would be multiple points of leakage: www.aspe.org/pipeline/is-supervisory-air-monitoring-feasible-for-manual-dry-standpipes/ Just wondering if I'm completely missing the boat here, or if there's something about this portion of NFPA 14 that I'm misinterpreting. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe In Class I standpipes, I commonly see a pair of hose valves installed at the top landing (or intermediate landing) - One immediately below the other.
Is this an incorrect derivative of the requirement to calculate the two most remote outlets (at 500 gpm), or something that was required in a previous edition of NFPA #14, or is this merely a regional practice that is a result of the shared DNA of my regional contractors? I thought I had seen an informal interpretation regarding this, but I cannot find it again. NFPA Figures do not appear to support this double-valve arrangement. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have been asked to supply FDC signage for an existing building with combined sprinkler/standpipe system.
The AHJ has requested that both minimum and maximum operating pressure be included on the sign. Can we use existing hydraulic data information or should it be recalculated including friction loss from the fire hose to pumper truck? Also, what would constitute the maximum pressure in a combined sprinkler / Class III system? Would it be max 175 psi at all 2-1/2” hose connections if there are pressure regulations devices on the 1-1/2” hose valves? Thanks in advance in helping us sort this out. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe During a recent life safety walk through of a popular boat show, I observed the installation of a temporary Class I wet standpipe system to supply various hose valves along the docks.
I noticed the 4-inch Silver-Line Schedule 40 PVC pipe was being supported randomly. I recorded distances ranging from 9 to 15 feet. I consulted with NFPA 14 then 13. NFPA 13, Table 17.4.2.1 shows "NA" for 4 inch CPVC pipe. In viewing the cut sheets for the listed pipe, the support spacing is 7.7 feet at 73 degrees F. My question is, is my methodology correct on how I went about getting the correct spacing in order to advise the the contractor? Please advise. Thank you. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Does the requirement in NFPA 13 that “All valves controlling water supplies for sprinkler systems or portions thereof, including floor control valves, should be accessible to authorized persons during emergencies. Permanent ladders, clamped treads on risers, chain-operated hand wheels, or other accepted means should be provided where necessary” imply there is a maximum height limit for floor control valves or standpipe isolation valves?
I have a couple standpipe projects where I am having trouble squeezing in a standpipe isolation valve down low (in elevation). I haven't found a confirmation in the standard or handbook that identifies a maximum height for accessibility. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a project which includes two 6-level buildings (a parking garage and a residential structure).
The garage is reinforced concrete and cold. The residential portion right next to it (8 inches away) is mostly wood construction and warm. The project has a seismic design category of B - so no earthquake bracing throughout. Because the garage is cold, I have the dry control valve on a combination standpipe in a warm closet in the residential portion. The 3" feed then travels across the 8" gap to the garage. This happens at all 6 levels. My question is, do I need a seismic separation assembly on one side or the other at each of the levels where the dry feed travels across the gap? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When doing a flow test for a 5-year on an automatic wet standpipe system in a building which has had significant additions over the years, which design pressure applies?
The original 8-story building and pump are from the early 1980's and was required to have a minimum residual 65-psi at the roof, flowing 750 gpm. Fast forward to the most recent building attachment to the existing fire pump, and the code now requires a minimum of 100-psi at 750 gpm at the roof. Would these additions be considered separate zones and therefore be tested individually at their specific design requirement, or would they all be tested at the original design requirements? The building is a healthcare facility and is inspected to NFPA 25-2011 per the Joint Commission requirements. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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