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
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Is it necessary to reduce the pressure serving hose connections or hose cabinets when there are the 1-1/2" or 1-inch hose connections installed in a facility?
What is the maximum allowable pressure for these type of hose connections? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Hi everyone - I need advice about jockey pump sizing.
The system we have has a city supply plus a booster pump. The city main shut-off pressure is 42 psi (2.9 bar) and the booster pump shut off pressure is 27.5 psi (1.9 bar). So, combined, the pressure is 69.6 psi (4.8 bar). The jockey pump pressure should be about 10 psi (0.7 bar) higher than the booster pump pressure. So, the jockey pump shutoff pressure should be 27.5 psi + 10 psi = 37.5 psi (1.9 bar + 0.7 bar = 2.6 bar)? Is this correct, or is the jockey pump shutoff pressure the combined 69.6 psi + 10 psi (4.8 bar + 0.7 bar)? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a project that is a 4 story residential building and within each bedroom unit there are soffits along each wall. These soffits do not exceed 24-inches.
Based on Table 12.1.11.1.4(c) in NFPA 13 (2019), it says we can neglect the obstruction and place our sidewall sprinkler off of the wall behind the obstruction. This situation I am describing is on the top floor where we will be providing sidewall coverage instead of pendents. My question is whether or not we can space the sprinkler as close as we want to the soffit along the wall, given it being less than 24-inches? I'm just having a hard time figuring out if the sidewall will be able to adequately protect the space under the soffit with not much parameters. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe My client in has requested single-interlock pre-action systems be installed to protect each of their two communication / hub rooms in their new facility.
Space is limited in the facility and it was suggested to install a pre-action cabinet inside each of the rooms, thereby serving the room itself. While a pre-action system cabinet/valve assembly cannot be installed in an area subject to freezing (application for cold/refrigerated storage) is there anything preventing the cabinet from being installed in the space it serves? Due to dry pipe system size constraints and distance, it is not possible to locate the cabinets in the sprinkler room. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have been given the work to a new school, and there is a storm shelter built into it.
We want to run our pipe over head from the fire pump room, which is not storm-shelter protected, and penetrate through the storm shelter wall to protect this area. I just want to confirm if penetrating through the storm shelter wall is acceptable to do. In the 2020 version of ICC-500, I understand it to read that penetrations shall not degrade the structural integrity and impact resistance of the storm shelter envelope. It also says that penetrations 2 ½ inches or larger in diameter should be considered openings and shall be protected in accordance with section 306.4 (impact protective systems and impact testing). Then, reading into chapter 6, which is fire protection systems, it states: “These systems are not required to remain functional for the design storm event and minimum period of shelter occupancy (24 hours for hurricane shelters, 2 hours for tornado shelters) or to be protected from the wind load and impact requirements of Chapter 3 or flood-resistance requirements of Chapter 4.” Is penetrating the shelter wall the best approach? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe For low-pile/miscellaneous storage, NFPA 13 has Group A protection up to 5-ft in height requires Ordinary Hazard Group 2 criteria. It also requires Class IV up to 12-ft as Extra Hazard Group 1.
Could you, theoretically, design for Extra Hazard Group I, but put the Group A in the 7-12ft range with Class IV below? There would be no commodities above the Group A plastics, but I'm not sure that the Class IV would be protected throughout properly. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a newly-installed electric (duty) fire pump, and a back-up diesel fire pump.
Each pump has a 100% required flow capacity for the system (750 gpm each) for the building. Is it OK to run the two pumps simultaneously during testing - which would result in a 200% flow? The diesel pump is only intended to be used during power interruption/worst-case, but not with normal power online. During testing, we release water in the test line (flow meter) - the pressure went down and triggered the cut-in pressure of both the electric and diesel pump which makes it run simultaneously (electric first, then the diesel a few seconds later). Does this not have a water hammer effect on the system? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We're currently working on a school project. There's a suspended ceiling throughout much of the school. The project requires "total coverage", but I'm not sure whether this applies above the ceiling, below the ceiling, or both.
We're under NFPA 72, but 72 does not seem to clarify this either way. Are smoke detectors required above and below ceilings, for "total coverage"? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe What constitutes an "accessible" vertical shaft?
We have a vertical shaft in a high-rise building, without a door at the bottom, but with windows. Is this "accessible" as dictated by NFPA 13? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a project that has carpet storage, per FM Global Sheet 8-30, Table 1. In that table, there are different K-Factor options with corresponding minimum pressures.
The existing sprinkler system has k-16.8 ESFR sprinklers. My question is whether or not I can utilize the existing k-16.8 ESFR sprinklers and just calculate them to meet the requirements of FM Global? In this case, it's showing a minimum required demand of 30 sprinklers at only 7 psi. Am I looking at this wrong? Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Where does "Bottom of Storage" begin in terms of storage height for low piled/miscellaneous storage?
So the warehouse I'm looking at has non-combustible liquid (Sodium Hydroxide. Corrosive and dangerous. Not flammable) in plastic containers that are over 5-ft from grade/floor because they are above an empty spill collection vessel. But, the combustible material themselves (the liquids in plastic container) is less than 5-ft from bottom of the commodity to top of commodity. It is only because it has to be above the spill collection vessel that the plastic could be over 5-ft? Does this still count as over 5-ft of plastic storage, even though what's underneath the less than 5-ft of commodity is just open air? Thank you all for your time. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I have an existing office building and we are renovating one floor. The building has an existing sprinkler system.
In the middle of the office floor, there is an outdoor patio (I believe all non-combustible) and it is open to the air above. It is 6' x 6' and surrounded by glass on all 4 sides. There are currently no sprinklers protecting this courtyard and we are being told that there needs to be. I am not sure which part of NFPA 13 I would even look at since Section 8.15 only discusses exterior projections and the like. Nothing about an open-air courtyard. I would appreciate any help. There is room to install dry sidewalls above the glass even though the sprinklers would be watering the outside. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Are there any restrictions (by code) for using a return bend on an ESFR pendent sprinkler?
We have structure in both directions, with 21-inch deep beams which requires the pipe be installed underneath the beams. Thanks in advance! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Do metal or steel pallets have any adverse effects on a storage system's (either racked or high-piled) sprinkler demand or density?
I know plastic pallets can increase the commodity classification of class I-class IV commodities, but I don't think metal does. I have a storage facility that can't use wood pallets but also can't protect the level of plastic commodities required without a costly fire pump. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have an external fire protection network in a marine port that has been served by 2 main electrical-driven fire pumps.
The proposed solution on this project is to utilize two main end-suction-type fire pumps using the seawater as a water supply source. The seawater is near the seashore at a lower elevation than the fire pump base. To overcome the low pressure of the Net Positive Suction Head, a vacuum priming pump is installed on the suction line to get enough pressure to prime the fire pumps. Considering this whole assembly is not listed nor approved, and there is no space for a water storage tank, what feedback might you have about the non-listed solution? We can't provide an extended platform here with a vertical shaft turbine pump, so I'm at a loss for solutions. Thanks in advance. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe I would like to differentiate between the density requirements for low piled and miscellaneous storage using NFPA 13-2019 Edition.
I have reviewed the the definition and literature in the code. That is all completely understandable. Does miscellaneous storage meet or excteed the requirements for low-piled storage? Based on the commodity, total storage area, total storage percentage, pile size dimensions, and storage spacing requirements - does all this factored in mean that the design density for the non-storage areas (like manufacturing or assembly) can be used under the miscellaneous storage area, instead of the densities provided in NFPA 13 Table 4.3.1.7.1? For Table 4.3.1.7.1 - there is no mention of low piled storage in the title of the table - is this the table that would be used for the determining the densities for any low-piled storage areas? Is there not a separate table for low-piled storage? I am likely overthinking things but some clarification or opinions would be appreciated. Thanks in advance for the help. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Working on a project with an underground water storage tank, where the water level is under the pump suction inlet. The pump type is a vertical turbine pump.
Is the a maximum vertical length of suction pipe for this type arrangement? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Is there a calculation method for sizing of air vents at the top of a sprinkler system riser?
NFPA 13 says 1/2-inch (15 mm), for a manual valve, but is there a way to calculate what this should be for a large system? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Hello everyone -
I have a problem with two identical fire pumps rated at 145 psi at 2,500 gpm. When testing for 0% flow and 100% flow the pump gives the correct pressure, but, when testing 150% flow the pressure drops dramatically, it has to show 125 psi and the result is 92 psi. The pumps has a 10-inch flange suction an as NFPA allows it was installed a 10-inch pipe directly to the pipe, no suction reducer, having 16-ft (5 m) long of distance for one pump and 19'-6" (6 m) for another one, the second one with two 45-degree elbows installed more than 10 times the diameter from pump suction. The tank is 23-ft (7 m), full of water. The test outlet is installed on the other side of the tank, so the flow does not fall over the suction inlets. The antivortex inlet has a plate of 7.5 inches above the floor. The pump discharge is 10 inch. The flow meter is 8-inch diameter with 8 diameters before and more than 5 diameters after. Any idea why the pressure at 150% is so low? 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 In Section 19.4.1.3(3) of NFPA 13-2019 Edition, discusses that rooms or compartments 800 sqft or less (small rooms) should be calculated based on delivering 0.10 gpm/sqft over the room or the compartment by using the area of the room divided by the number of sprinklers in the room.
I believe I've overcalculated remote areas in the past. My project now is an apartment building designed according to NFPA 13. Using residential type sprinklers with non-sprinklered combustible concealed spaces. According to Section 19.4.1.2 I need to calculate a minimum of eight sprinklers. In the past I've calculated the eight sprinklers using the actual spacing based on the S x L rules with a 0.10 gpm/sqft density. One room example - room dimension of 24 x 12 is 288 sqft. Two sprinklers spaced in a compartment 8'-0" off one wall and 6'-0" from adjacent wall. Using the S x L rule: 16' x 12' = 192 sqft x 0.10 gpm/sqft = 19.2 gpm each. Or, according to Section 19.4.1.3 (3), would I divide the room size 288 sqft by 2 sprinklers, which is 144 sqft per sprinkler, regardless of the actual sprinkler distance from the walls? This second scenario would result in a 14.4 gpm required flow. Or, was the code option (3) assuming the sprinklers are evenly centered within the compartment. Thanks in advance for your input and clarification. Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe Happy New Year everyone!
We are upgrading protection for one of our Crude Oil Storage Facilities for a major oil and gas clients in the Middle East region. We have 4,000 gpm diesel driven pumps for fire water use. There are 8-inch pressure relief valves provided, per Section 4.20 of NFPA 20-2019. Section 4.20.4.1 (Type) reads as "pressure relief valves shall be either a listed spring-loaded or a pilot-operated diaphragm type." My interpretation of this section is that the listing is required in either of these cases, whether it's spring loaded or pilot operated. However, it's being challenged by those who are reading word-to-word meaning and saying that the listing requirement is only applicable for spring-loaded, and not for pilot operated relief valves as the sentence is separated by "or" along with the latter "a". If the letter "a" is not there, then I'm convinced with my interpretation that the listing is applicable for both cases. Also, I checked the handbook but it does not provided any further detail. Has anyone had any insight/experience as to whether the listed requirement applies to pilot-operated relief valves? I appreciate any further detail or discussions on the above with reference to code interpretations. Thanks! Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe We have a project light hazard occupancy, that is a highrise building, and has glass all along the perimeter of the building.
Is the maximum sprinkler spacing measured off the knee wall, or the glass? There is a knee wall that rises up from the floor 2'-6" and is 12-inches in depth. Do we measure the 7'-6" off this knee wall for floor coverage, or do we measure off the glass for the maximum distance? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe |
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