We have an auditorium project with a walkway that is constructed beside the seating area at the first and second levels. The second level has been provided with beam-type smoke detectors. 

There is a suspended ceiling below the walkway which is approximately 6-feet (2 m) from the wall. Do we need smoke detectors below this suspended ceiling?

The design currently has smoke detectors only inside ceiling void spaces below the walkway - is this in compliance with NFPA 72?

The fire alarm contractor is arguing that if a fire originates at the floor level below this walkway, it will be easily detected by the beam detector at the second level due to the smoke buoyancy. 
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Do you know of any specific guidelines for space around a fire pump skid to leave in a fire pump room?

I have always worked off the notion of "enough clearance to get around and work on a pump" but that is very subjective. So, I have a self-imposed 3-foot clearance around the edges of a skid. 

Is there anything more specific in generally adopted codes or standards?

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We are in a fire sprinkler retrofit and we have steel joists and decking throughout the building, with mostly masonry block walls. It's a single-story structure.

Where there are doors, however, there is wood framing above the grid ceiling.

How much wood constitutes an issue requiring fire sprinklers above the ceiling?

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I have a question about protection of sprinklers in windows specifically for a connection of a basement parking garage and a first level mall commercial space.

NFPA 101 accepts that there is a connection between both occupancies, but there must be compartmentalization of 3-hours without automatic sprinklers and 2-hours with automatic sprinklers. In this case, we have an escalator from the basement up to level 1, as shown below:

Can we consider this to be compartmentalized with glass and sprinklers on both sides of the glass?

Do the access doors have to be 1-1/2 hour, our could they not have any fire resistance if I have sprinklers on both sides?

This project is under NFPA 101 (specifically Table 6.1.14.4.1 for separation between occupancies), NFPA 5000, and NFPA 13 (9.3.5/19.4.3 for sprinkler protection of windows).

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We have a large production facility where there is an isolated small room that is remote from the sprinkler riser room. This small room houses tools and other equipment which the owner sees as valuable property and does not want it to get wet unnecessarily, especially during trip testing when they test the deluge system. 

The sprinkler system is an open-head deluge system, except for these few regular pendent sprinklers.

Are these pendent sprinklers acceptable to be installed on a deluge system?

I was under the impression that only open-head sprinklers could be used on a deluge system.

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I'm working on a project with an overhang that has patient rooms above. The ceiling of the overhang serves as a "canopy" for ambulances, which will back in under the overhang to protect patients from the elements when unloading the ambulances.

The design and completed construction do not include any fire suppression including sprinklers.

Are sprinklers required for this canopy?

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We are sprinkler protecting a building with all I-Beams (W-type) and they are considered Obstructed Construction. The maximum beam depth is 20-inches. All my deflectors are 20" down from the deck. 

The owner now wants to put sound panels in each of the beam pockets which will take up about 85% of the space and will hang level to the finished floor but at least 9-inches up to 19-inches down from the deck because the steel slopes.

Would additional sprinklers be needed above these sound panels?

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When/why would an eccentric reducer ever be installed on a fire pump's suction side with the flat side on bottom?

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Is it permissible to consider the refill supply for a water storage tank when sizing the tank?

The supply would come in above 20 psi. Thanks in advance.

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Where exactly is a remote area for a fire sprinkler hydraulic calculation drawn with respect to interior and exterior walls?

Is the remote area boundary along the inside, centerline, or outside edge of a wall?

Also, are small wall cavities or unsprinklered shafts right in the middle of a remote area included in that remote area square-footage?

I recognize that as much as I can fine-tooth a layout this really doesn't matter much in the overall scheme - and I typically would add a sprinkler or two to a calculation if the exact location of the remote area boundary would make or break an area threshold - but I've been curious about this as I'd like to be consistent with code and what should be done.

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We have a project where the AHJ is telling us they want the waterflow alarm to be silenceable. Our understanding under NFPA 13-2019 7.7 and 28.2.3.1 is that there must be an audible alarm within 90 seconds (per NFPA 72) and must continue until the flow stops, not when the fire alarm system silences the flow.

Are we correct in that waterflow is a non-silenceable event, by code?

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A couple recently submitted questions relate to the same topic: 

(1) Extra hazard, grid pipe layout of approximately 1,800 sprinklers. What is the criteria that drives the specific number of sprinklers that will be operating together?

(2) What's the best way to determine the design area and number of sprinklers within a calculation for a parking garage?

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I have a project with cloud ceilings that are 80 sqft clouds with a 2-foot separation around each cloud. I have no intention of omitting the sprinklers above the clouds. I plan to locate sprinklers in each cloud, considering them obstructions greater than four feet.

Do I need to space the sprinklers in the clouds to just cover beneath the cloud?

Just want to confirm that spacing doesn't need to be across the cloud ceiling when sprinklers are in different clouds. Thanks in advance.

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I have a double fire wall (two masonry walls next to each other with small air gap in-between). I need to have a door in each wall.

The doors would have to swing opposite directions, I think, which means a double Firewall could not be used in an egress condition where doors both have to open in the direction of travel to the exit.

It sounds like I need a tied or cantilevered Firewall instead of a double Firewall. Is this correct, or are there any other approaches to a door within a double Firewall?

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We have a project where transformers are located on the periphery within a building's ground floor. There are 14 transformers within a single room. The life safety consultant has recommended for us to provide deluge system protection.

Is it required to provide a deluge valve for each transformer, or combine three or four transformers per valve?

Also, how should sprinkler flow demand - is it calculated by each nozzle, or should we consider the entire transformer area for protection? Under NFPA 15 we have assumed 0.25 gpm/sqft (or 10.1 lmin/sqm).

​Thanks in advance.

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Does anyone know of a dry-chemical or equivalent fire suppression system that can be used in cold environments (as low as -20 degrees Fahrenheit)?

The space to be protected is a testing chamber approximately 8 feet by 11 feet (made of combustible materials). Automatic fire extinguishers are not an option as they don't have any UL rating. Thanks in advance.

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I have a project where there are multiple cloud ceilings with minimal gaps in-between. The clouds are 3'-6" wide, and the gaps between them are approximately 3-inches. Below is an image of the reflected ceiling plan.

Are sprinklers required below these cloud ceilings? Thanks in advance.

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I have a project where the fire pump room is located on a third floor level.

Are there any specific requirements regarding the location of a fire pump? Is this location acceptable?

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What design options do I have with a fire sprinkler design to address protection underneath a 45-degree pitched roof?

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By code, does the check valve on the discharge side of a fire pump, or jockey pump, need to maintain any specific distance from the pump itself?

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We're always thankful for the expertise and input shared with this collaborative community. The wide range of voices (from designers to AHJs, inspectors and engineers) is great. Here's a thank you to all our contributors, especially our Top Ten for October:

We are designing a residential building that will have a manual wet standpipe in a fully-sprinklered building. The building itself is less than 75-feet high.

I need to calculate the wet manual standpipe but would like to check my approach. 

Do I need to calculate the remote standpipe at the two most remote hose valves at 100 psi, 250 gpm each, plus one more hose valve closer to the source at 250 gpm all the way back from a supply at the fire truck?

​Thanks in advance for any feedback.

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I have a question regarding the need to provide electrical classification for a building using Class 1A flammable liquids.

For this building, 4 gallons could be out in use (located anywhere in the building). The MAQ is 10 gallons. I have discussed this with NFPA 30 committee, the manufacturer, and the AHJ (who is a knowledgeable FPE). They have all determined that even if the MAQ is not exceeded, electrical classification is required if a flammable/explosive mixture could be present.

The NFPA 30 staff directed me to a provision in NFPA 497, Section 5.5, that if the materials will not reach 25% of the lower flammable limit (LFL), this could be utilized to justify not providing classified electrical fixtures.

Does anyone know how to do this calculation, or know of firms that can be hired to do this?

I am an FPE and do not know how to perform it, and I have spoken with other FPE’s who also are not aware. The gentleman I spoke with at NFPA 30 agreed it would be by an industrial hygienist or a chemical engineer and not an FPE.

But does anyone know any that can be hired for a one-off calculation, or have a place where I could learn how to perform it myself (NFPA reference, SFPE article, course, etc.?).

Thank you!

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We have an existing building were the highest occupied floor is less than 30'-0 above fire vehicle access. This building is being renovated.

Part of the renovation involves the construction of a new building to be connect to the existing building. The new building is higher than 30'-0 above fire vehicle access. The exit stairwells in the new building need a standpipe system.

Does the existing building need a standpipe system since it is connected even though the existing building stairways and floors are not higher than 30'-0 above fire vehicle access?​

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