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NFPA 14 states that "hydraulically designed standpipe systems shall be designed to provide the waterflow rate required by Section 7.10 at a minimum residual pressure of 100 psi at the hydraulically most remote 2½" hose connection and 65 psi at the outlet of the hydraulically most remote 1½" hose connection" (Section 7.8.1, 2019 edition).
So does this mean if you have a single 2½" hose valve on your project, you need 100 psi residual at that valve? This seems pretty cut and dry, but I've been thinking about this, and off the top of my head, I can list at least 5 projects that had 2½" hose valves and less than 100 psi of static pressure on the ground floor, let alone 100 psi residual on the 4th floor. Not only projects that I have personally witnessed get signed off, but also buildings I have found myself walking through that have had gauges on the hose valves, and those gauges more often than not (in my area at least) read a pressure less than 100 psi static. Are these just all designed wrong? Or am I missing something? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
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Section 9.2.2 in NFPA 14 allows protection for a standpipe that is not in a stairway to be "the piping is enclosed in fire-rated construction with a rating equal to that of the enclosed fire-rated exit stairway." In the Gypsum Association Manual WP 3910 for a chase wall with staggered studs has a rating of 2 hours. Does such a 2-hour rated chase meet the intent of NFPA 14 when the standpipe is not in the stair? Thank you for your feedback! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  We're looking at "refuge areas" per 2024 IBC (not to be confused with "areas of refuge" in NFPA 101) within smoke compartments to satisfy the requirements for smoke barriers in Group I-1, Condition 2 in the IBC. Can the "refuge area" be calculated to include portions of the floor/smoke compartment that are open to the exterior of the building? For example, an occupant load of 80 persons receiving care on the fifth floor of a Group I-1, Condition 2 occupancy would require a minimum of two (2) smoke compartments to be provided (420.6). Each smoke compartment must be provided with a refuge area sized to accommodate 15 sqft/care recipient plus 6 sqft/other occupant and "areas or spaces permitted to be included in the calculation of the refuge area are corridors, lounge or dining areas and other low-hazard areas" (420.6.1). If each side of the smoke compartment is provided with an exterior lounge/amenity area, may this be used as the "refuge area" to meet the minimum required square footage?  Before people say, "Ask the AHJ," I am him; he is me.
I have an applicant who has combined plots of land with a mid-rise and some detached townhouses. A shared fire line supplies the two structures, but only the mid-rise FACP monitors the supply tamper. The townhouse FACP will not know if the water is off (except for the tampers at the risers within the townhouse). The buildings are owned by the same ownership. They are arguing they are technically meeting IBC 2015 903.4 "Valves controlling the water supply for automatic sprinkler systems, pumps, tanks, water levels, and temperatures, critical air pressures, and waterflow switches on all sprinkler systems shall be electrically supervised by a listed fire alarm control unit." It is being monitored, but the fire marshal and I are of the opinion this doesn't provide monitoring for the townhouse and does not meet the intent of the code. Does anyone have any thoughts on whether a shared line can be monitored by only one building that it serves? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe My company is hiring a contractor to install our central station headend equipment (servers and software).
I would like to include the testing requirements in the statement of work. I looked through NFPA 72-19 Chapters 14 and 26, as well as other chapters and codes. I do not see the requirements for central station headend testing. I think the subscribers will need to ping the central station with the date, emergency code, building, etc. Does code require a minimum amount of information the subscribers must send to the Central Station? If so, could you tell me the required subscriber information that needs to be sent to the central station or provide the location in code for the information to be sent to the central station from the subscribers? I don't see any requirements or criteria for testing, and I want to be sure we're conducting this appropriately. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe My company just completed design/build construction of a canopy structure over a courtyard between two restaurant buildings located on the east & west sides. We assigned an Occupancy Classification of A-5. The structure is all steel, other than the roof construction is comprised of the following layers: 22 gauge steel B deck, 7/16 inch OSB, 24 gauge metal standing seam. The standing seam contractor asked for a solid substrate, instead of metal to metal (Standing Seam attached to the B Deck. We agreed to add the OSB. We examined the 2018 IBC and assessed that we could use the OSB. Our assessment concluded that the entire structure could be built with wood framing without sprinklers (A-5, no enclosures, height 37ft, 6,090 sf, Type V(A) Construction). The AHJ shut us down and told us we needed to remove the OSB (combustible material). What we didn't know was that the City and developer executed a Covenant Agreement that stipulated the Canopy was an A-3 Assembly occupancy. This was arranged because the developer didn't want the exterior restaurant walls to be fire-rated because of the ease of movement from the restaurant to the courtyard. As a result, the OSB needs to be changed to fire-retardant-treated plywood. Was the original classification of A-5 occupancy (which could have been wood) canopy assembly an acceptable approach? Picture below, showing the galvanized steel deck. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  I have a small 580 sq. ft. attic, fed by a dry system, next to a wet system in a retail outlet mall. They are 2 separate systems at the valve assembly. The ceiling for the dry system is 10-ft higher than the wet system.
Would a phantom flow be required here? If so, would it be added at the valve assembly, where they meet? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We are working on hydraulic calculations for a military hangar, and we are referencing UFC 4-211-01, which calls for the design area to be 0.20 over 5000 sqft.
The hangar is 60 feet tall at its peak. To prevent overflow, we are proposing K5.6 sprinklers for the area. Are K5.6 sprinklers allowed, or does UFC 3-600-01 apply where buildings 45-ft up to 60-ft would require minimum K11.2 sprinklers? The area is overflowing by around 600 gpm. Any advice on this would be helpful. Thanks. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For forward-flow test connections, is a 4-ft length of pipe inside the heated space required?
NFPA 13 Section 16.10.4.9 would require this of any main drain test connection. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am designing a wet pipe fire sprinkler system in a one story Group B occupancy (16-ft high). The building is about 90,000 sqft in area. The building will be fully sprinklered with two zone control valve assemblies.
The fire department is asking to add fire hose valve cabinets as the interior remote areas of the building are more than 130 feet from an exterior door, only citing that its required by IBC 2021. Is this correct? I can't find this requirement. Any help is appreciated. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For a fire sprinkler system, if you have a loop running around a typical hip-roof attic, and you have a center riser, can you tie it into the loop in two locations?
NFPA 13 doesn't really discuss when a looped system turns into a gridded system. None of the branch lines would be connected, so in my opinion this would be acceptable as long as you meet the discharge time through the remote inspector's test connection. What are your thoughts? Is this a gridded or double-loop systems? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What is the industry standard or method used for determining the design area size in order to do the hydraulic calculations for Window Sprinklers in terms of the "Adjacent Sprinklers?"
What is the definition of "Adjacent Sprinklers?" Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When dealing with combustible soffits, what are the conditions where a soffit is big enough to warrant a sprinkler inside?
In our case, we have wood constructed soffits with sprinkler protection below and adjacent to the soffit. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For NFPA 13D and a single family home of 1,000 sq ft, what is the optimal k-factor I should be considering?
In this particular project, we don't have a city water supply but we do have a good well. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe How would you recommend protecting a dry room for battery operations, such as battery testing or packaging?
I've been designing these with dry systems but was curious if there are any codes to omit sprinklers, or if anyone uses clean agent systems? If you use something alternatively, why do you go that direction? Moderator's Note: Dry Rooms for batteries have less moisture to avoid corrosion and any chemical reaction for the batteries, which would degrade or reduce performance. Very low moisture is the key for a dry room for batteries. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a sprinkler system in a 75,000 sqft self-storage facility. There are upright sprinklers that are within 2" of a vertical support Unistrut that is used to separate storage spaces. Would this be considered obstructed? What is the code-basis for evaluating a vertical obstruction like this?  If a duct detector is installed, and the mechanical unit has a capacity of less than 2,000 CFM, it is required by code for the duct detector to be connected to the fire alarm panel?
Alternatively, removing the detectors can be considered in this situation. Looking for relevant code and standard basis. We're under the 2021 IFC, 2021 IBC, and 2019 NFPA 72. Thank you! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Does anybody have experience with locating diesel fire pump fuel tanks in exterior locations where the local ambient temperature can drop to below freezing point?
We have an unavoidable situation where we have to locate the fuel tank outside the pump room and we're hoping not to have to build a heated enclosure. NFPA 20 seems to require a heated enclosure, but FM not so much. I am aware that condensation and fuel deterioration are issues to be dealt with, but I was thinking maybe good quality thermal lag of the tank and feed/return fuel piping may be sufficient with just a roof structure above the fuel tank. What are your thoughts on this? any thanks in advance for your thoughts and advice Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a 35' tall, 79,103 ft², non-combustible building, which is a cooler in a cheese factory. There are two dry systems at the ceiling uses CMDA heads. There are single and double row racks throughout the cooler. The top of the rack 22' top of storage is roughly 26'. The racks have a single layer of 5.6K in-rack sprinklers at the top of the 3rd level. There are 5 levels of storage, which includes the storage setting on top of the racks. The in-rack sprinklers have their own valve at the riser. It is a Class II commodity to 30'. The original design was done years ago and my question is not about the original design. In a single portion of the cooler the owner is taking a 32' section of the existing racking out and installing new racking. The new racking will have the same amount of levels. The bottom 3 levels will have a "cooling cell," one on each level.  I have never heard of a cooling cell on a rack like this. Not sure what the cooling cell is made of. Does a cooling cell increase the protection level from Class II? If so, how much would it change the commodity classification? Does NFPA 13 even address something like this? My assumption is that it will increase the hazard and call for greater level of protection. I have asked for the data sheet for the cooling cell and hope that it gives direction for fire sprinkler coverage. I have attached a picture, which really doesn't give a lot of information. Has anyone run into this before? Thank you! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe My jurisdiction (I am the AHJ) has had several buildings built with private hydrants supplying the sprinkler system where the main comes into the building, through the RPZ, feeds the sprinkler system/standpipes, and leaves the building and feeds the hydrant(s).  This has always seemed counterintuitive to me, at best. I feel we are "robbing Peter to pay Paul" and have wondered if this arrangement will adequately supply the sprinkler system when we (FD) pull water from the hydrant and pump it back into the FDC.
Per our state law, private hydrants have to be "protected" with a backflow. Is this configuration code compliant, and if not, what is a solution? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe February flew by! Thank you to our Top February Contributors for sharing their expertise.
What specific criteria or code references determine whether a standpipe system is classified as 'separated' rather than 'combined'?
I've seen AHJs state that even though the sprinkler system and the standpipe have separate vertical riser assemblies (control valve, check valve, and supervision), they are fed from the same underground supply (one underground service main) and will still be considered combined. We are working on a project where the AHJ has deemed the building 'partially sprinklered,' requiring the standpipe to be upgraded from 4" to 6" (which would necessitate a pump) but only if it is a combined system. We are looking for clarification or language that supports the distinction between a combined and a separated standpipe system to explore options that may avoid the need for a pump. Additionally, does anyone have thoughts on how we might be able to keep the standpipe at 4" or explore alternative approaches to avoid the pump requirement? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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