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I'm trying to establish a way to avoid dry valves/dry systems to protect trash and line chutes early in project development. I've heard of freezing issues due to roof venting or other ways that cold air can fill the chute (perhaps from the bottom when trash room doors may be open to the exterior during severe cold).
I know most or maybe all of these fabricated chutes come with fire sprinklers, but are they usually essentially built-in dry barrel sprinklers? If not, how can we ensure they won't freeze without using a dry system? The specific chute submittal or product information is usually not available until well after space for a dry valve should be set aside. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
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We're designing a fire suppression system for a garbage truck maintenance facility which will include a welding bay. NFPA 13 (2019) is being used. I am using OH2 for the maintenance bay but I'm not sure about the welding bay.
Is a welding bay appropriately designated as Extra Hazard Group 1? I can't find anything in NFPA 13 that speaks specifically to welding. Thanks! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Regarding light fixtures as obstructions to sprinkler spray pattern per NFPA 13D - many hanging pendant light bases are slim (1”-2” off ceiling) and do not obstruct or prevent cold solder, but the lighting housing hanging below the base (anywhere from 12”-72”) is to be considered an obstruction? Are these described hanging pendant lights also to be considered obstructions and to remain 36” away? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  I have a dry system that is tripping when the county runs their test on the hydrant using tankers and pumpers.
My question is, if I use a 3/4' relief valve, will it be enough? How much flow (gpm) will it flow, at its maximum flow rate? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What does “horizontally away from the sprinkler” mean?
I recently read a technical note regarding the ESFR obstruction rule. The example question was: *“In an existing building, a 6-inch-wide steel brace runs diagonally from column to column, forming an ‘X’ between four columns. The brace is located a minimum of 48 inches below the ESFR sprinkler deflectors. Should this brace be considered an obstruction to the sprinkler discharge pattern?”* The answer stated that the X-shaped braces are not considered an obstruction because they are located at least 1 ft away horizontally from the sprinkler (referencing NFPA 13, 2016 edition, 8.12.5.3(3)). My confusion is this: if something is located below the sprinkler, I would describe it as being vertically away, not horizontally away. Did I interpret the code incorrectly? Can someone clarify the difference between “vertically from the sprinkler” and “horizontally away from the sprinkler?" Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I am performing a design on an existing system that was 3% AFFF and we are converting it to 3x3 NFF. Bladders, proportioners, concentrate lines are being replaced and all sprinklers being replaced to meet the specification for the new concentrate.
In the spec it has been requested to utilize the "water equivalency test method," which is outlined in NFPA 11. I've performed installs, inspections of foam systems for 10+ years, I've never seen this method installed and not very versed in how it really works, only from what I've read. There's not much information out there. Have you used this method? What have the requirements been for testing this method? Were you given outside specifications? Does any additional information exist for detail? I'm wanting to be sure we're compliant from a design and install perspective. I'm following the diagram supplied in NFPA 11-2016. "D.5.2.3 Water Equivalency Method. In this approach, water issued as a surrogate liquid in place of foam concentrate. The initial acceptance test(s) are conducted with the actual foam concentrate using equipment similar to that shown in Figures Figure D.5.2.2(b) and Figure D.5.2.2(c): real-time pressure, flow, and conductivity measurements are recorded with the actual foam concentrate to determine that the system is pro-portioning accurately. Immediately following this test, a water equivalency test at the exact same pressure and flows as in the initial foam discharge test is performed after isolating the foam concentrate tank. Example test setups are shown in Figures Figure D.5.2.3(a) and Figure D.5.2.3(b). This provides a baseline for comparison using water only for follow-on routine inspections and tests." Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe A customer wants to install a burglar alarm in a new building. They would like to add fire detection to the system. The building is not required to have a fire alarm system.
Can we run the heat and smoke detection off a security panel, or do we need to have a separate FACU? I have looked in NFPA 72 (2010 edition), and I see non-required systems in Chapter 23. I see if it is a combination system the fire signal takes priority. However, I’m still not sure if we can use a security panel. The state is under NFPA 72, 2010 edition and 2012 IBC & IFC. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Has anyone ever conducted puff testing for a gas fire suppression system?
The owner is requiring us to perform this test, but I have never done it on previous projects. I checked NFPA 2001, and its requirements for flow testing are not detailed enough. I would like to know the specific procedures for conducting this test, as well as the key considerations to keep in mind. Ideally, I'd like to find a specification document or procedure to follow. Advance Thanks！ Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe If a warehouse is getting a new tenant, and the AHJ requires a new C of O, does the sprinkler system need to meet current standards (NFPA 13-2022) or can the original standards (NFPA 13-2007) be used?
Specifically looking at Group A plastic protection requirements here. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA mentions some sidewalls specifically listed for installation up to 18" below the ceiling.
Does anyone know a manufacturer that makes them? All I can find is up to 12". Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We are running into a lot of gas unit heaters in warehouses with ESFR protection.
Two issues have come up: (1) NFPA 13 2019 Table 9.4.2.5(a) clearly shows the high temperature zones around (horizontal discharge) heaters. Given there are no high temp ESFRs, we have told contractors they can install the heaters 7' below the sprinkler deflector. The GCs do not like this and claim they have not had this issue with other ESFR installs (not ours). (2) The heaters are large enough to be obstructions to ESFR sprinkler discharge. We must install a sprinkler underneath, but the same issue with the temperature rating comes up. We have considered somehow adding an additional "barrier" around the bottom of the heater, so that the ESFR sprinkler is 2'-0 below the heater (but directly under the barrier). This is also not a welcome idea by the GC. We also do not have an actual example of this approach. Is there information we are missing here? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a facility with an NFPA 13 Extra Hazard 1 sprinkler system.
The client's proposed location of the water storage tank is approximately 33-ft (10m) higher than the level of the protected building and around 100-ft (30m) away. The client's proposed pump house is closer to the building, separate from the tank. My question is - is there a maximum length for the suction feed from the tank to the pumphouse under NFPA rules (13, 20, 22)? I would rather locate the pump house next to the tank and run the delivery main to the building. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When does a Community Room trigger the need to use NFPA 13 as opposed to NFPA 13R? If the first floor of a 3-story apartment building is a meeting room, does the building, or perhaps the first floor need to meet NFPA 13?  Thanks in advance.
Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe When did NFPA 20 start requiring exterior access to Fire Pumps?
I have an older fire pump, sprinklers had to be tested at 50 years, and when this thing was installed, they had no exit door in the pump room. Current NFPA 20 in our jurisdiction (2016) calls for an exterior access door or access from an enclosed stairway or different exterior exit. The AHJ is aware of that. (Sections 4.13.2.1.1) Because it's an older system, I'm trying to see if the exterior exit requirement still applies to the system at the time of original approval. The oldest NFPA 20 I can get for free on NFPA Link is 1996. I cannot find this requirement or the "equipment access" section in this code beyond some parts about when a fire pump is installed wholly outside the building. Anyone with more experience than me know when this started? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a building that is changing from storage to a gymnasium.
Would the existing ESFR sprinklers be allowed to be used and spaced more than the 100 sqft? I have several sprinklers too far off walls in the existing placement. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have a mixed-use building, retail ~6250 square feet on the ground floor with residential occupancy on the 2nd and 3rd floors. The building is a mix of wood construction with bar joists, with a ceiling attached to the bottom chord of the bar joist.
These bar joists have the bottom and top chords made of wood with 1" steel tubing to create the open bar joist. My question concerns 2016 NFPA 13, Section 8.15.1.2.4. Can I classify these open hybrid joists as noncombustible bar joists? The ceiling is flat without access to the space. The ceiling assembly between the retail and the 2nd floor residential is 1-hour rated. The big question is, can we use the exception 8.15.1.2.4 and not provide sprinklers in the space above the ceiling? If not, I was told that if the ceiling assembly was two hours that the sprinklers in the concealed space can be eliminated. I haven't been able to find this in the NYS Building and Fire Codes. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We installed UL Listed grooved fittings with a rating up to 300 psi. The churn pressure of the fire pump is reaching 355 psi. The AHJ is asking for UL Listing or FM Approval to be above this pressure.
Is it mandatory under NFPA to have a UL Listing or FM Approval for the grooved fittings to cover the churn pressure, or is up to 300 psi acceptable? What are our options here if we have to do anything? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe NFPA 25 (2020) notes that standard response sprinklers are to be tested or replaced after 50 years in service, and quick response sprinklers after 20 years in service.
An issue arose regarding standard response 5mm glass bulb recess sprinklers installed / manufactured in 1990. The heads are RASCO Model F156. The data sheets note standard response. My understanding is that these sprinklers, being standard response, should have a 15-year service life before testing. Others in the trade have different opinions (including a manufacturer rep) due to the operating element being a glass bulb. Prior to contacting the manufacturer, I'd appreciate the forum's thoughts on whether the glass bulb or the fusible link is a determining factor in the required time for sprinkler testing. Thanks! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Can black steel be used for trapeze support? We have a project where the contractor has hung the sprinkler pipe with trapeze hangers from a piece of black steel pipe, anchored to the deck instead of directly to a piece of Unistrut or angle iron. Looking at NFPA 13 Chapter 17 (17.1.2, 17.4.1.3.1), it seems like this method is not allowed. Can you provide some insight as to whether this is allowed, or the pipe needs to be Unistrut, angle iron, or something else? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  For the protection of steel columns using sidewall sprinklers, what is the k-factor and temperature rating needed?
The existing upright sprinklers for the high-piled storage are 286°F. I couldn't find information for this in NFPA 13 2022. Any help or advice would be greatly appreciated. Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Hi all, we are working on a project where we have installed a dry preaction system, with a main pipe along the ceiling, which has a conventional upright protecting the upper sections of the area, while pendent sprinklers protect the lower parts of the area. Pendents are standard response sprinklers. Length of the pendent is around 16 inches (400 mm). I would like to understand a few things related to the dry system: Are these systems pressure tested pneumatically or hydraulically, or both? If tested hydraulically, water will be drained, but the pendents will still be filled with water, correct? Is this acceptable? The temperature is the area that should be above 68°F. The pipe is galvanized. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe  NFPA 13, 2019 Edition, Section 8.6.22 states, "Premixed antifreeze solutions of propylene glycol shall be permitted to be used with ESFR sprinklers where the ESFR sprinklers are listed for such use in a specific application."
Are there any current ESFR Sprinklers listed for use with antifreeze? I am currently only finding obsolete sprinklers that were listed for such use. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Regarding the QR sprinkler reduction: where does the -3 formula slope come from and where does the +55 come from in the equation Y= -3x /2 +55?
I've asked a few designers and they don't know. They said it is just something that is "Baked in," much like the Hazen-Williams formula, which includes elements we just accept. However, I'm just curious and like knowing things like that. Thanks for any help. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We're replacing old fire sprinkler systems in an existing warehouse in the mid-atlantic region with new ESFR systems.
The old warehouse house skylights every 25ft (which is a lot more than we see in new warehouses being built). No sprinklers are required in the skylights due to the size, however the number of skylights does raise questions about ceiling temperature. NFPA 13, 2016 Table 6.2.5.1 shows a maximum ambient ceiling temperature of 100°F for ordinary temperature sprinklers. It seems unlikely that the ceiling temperature would exceed 100°F in an occupied warehouse space (even on a hot summer day), so I'm thinking it make sense to install all ordinary temperature sprinklers (besides around unit heaters) to not delay sprinkler activation, but it looks like the newer editions of NFPA 13 allow of intermediate temperatures to be installed throughout warehouses. Is anyone seeing all intermediate temperature sprinklers installed in warehouse systems to prevent accidental discharge? NFPA 13, 2016-2025 all essentially say sprinkler temperature ratings for ESFR shall be ordinary unless Section 8.3.2 / 9.4.2 require intermediate- or high-temperature sprinklers. (Section 8.4.6.5 in 2016, 14.2.6 in 2019-22, 14.2.5 in 2025) Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe During on-site install (such as grooving, threading, and collisions during handling), its possible to damage the galvanized layer of the pipe.
How should we best address this? Is spraying anti-corrosion paint on the damaged areas the best option? Something like a galvanize spray or are there other better treatment methods? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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