I'm working on a performing arts theater in California. There are floating clouds with pendents in them.

I seem to remember an inspector bringing up an NFPA requirement for either a swing joint or a flexible drop to connect to the pendent sprinkler. I can't find anything in the 2016 Edition of NFPA 13.

Is there a requirement for a swing joint or flexible drop for a cloud?

Could anyone provide a code reference?

Thanks in advance.

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For a workshop paint spray, is there a delineation for when NFPA 30B is applicable?

I am working on a maintenance shop which has a few spray paint cans. Since they are aerosols, NFPA 13 says to use NFPA 30B which has some pretty drastic requirements for design density.

Yes, the easy answer is a flammable storage locker, but has anyone ever had to design to the full requirements just by the mere presence of paint spray cans?

Thanks in advance.

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For a horizontal split case fire pump, 10 pipe diameters of straight pipe is to be provided for the suction inlet.

My design includes a gate valve and strainer within the 10 pipe diameters.

Is the strainer allowable in this range?

I'm unable to find in NFPA 20 any input on this. Thanks in advance.

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What is the proper point in a system to take the antifreeze sample? 

I have taken readings at both outlets at the check valve, unfortunately a contractor is saying to take it at the most remote point. Those locations are either 25-feet in the air, or not installed at all.

Thanks in advance.

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I have (2) different storage scenarios with the same product. They are empty 5 liter HDPE containers from 2 different manufactures and packaging slightly different but both having cardboard dividers and on wood pallets.

I am leaning towards exposed expanded encapsulated Group "A" on the pallet load without cardboard sides due to the row of containers enclosed in plastic bags.

The pallet load with the cardboard partial sides and full cardboard top would be the same due to having only partial sides.

Any help would be greatly appreciated. 

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I have question regarding fire pump capacity.

In my situation the water department is requiring a city tap size to be 2 pipe sizes larger than the fire protection backflow preventer.

In my project, I was using a 4" backflow and 400 gpm fire pump so my underground/city tap would be required to be at least 6 inches.

The AHJ is requiring me to increase the area size in one of my remote areas. So, my sprinkler demand now becomes 582 gpm. To avoid having to use a 500gpm fire pump (with a minimum suction size of 6-inch) and increase the underground to 8-inch, could I still use the 400 gpm fire pump to supply the 582 gpm demand?

This comes out to about 145% of the pumps rated capacity.

I have never come close to the 150% mark before and just want to see what others think. If the underground size wasn't required to be 2 inches larger I wouldn't even think about it and go with the 500 gpm pump.

Thanks in advance.

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We have a project where we're adding a sound (anechoic) chamber and and protecting it with clean agent.

A question came up as to whether or not dampers are required for the HVAC system that provide supply and return air to the pre-manufactured chamber.

Is an anechoic chamber required to have dampers for limiting the migration of the clean agent?

My thinking is that the clean agent will be activated by an air sampling system, so there should be no meaningful amount of smoke in the chamber.

That said, do the dampers have to be listed for fire/smoke? 

Any help with getting specifics from code or a clearer understanding is always appreciated from the community so thanks in advance.

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We are working on freeze protection for an enclosed canopy which is also attached to the main building. There is no exposed metal pipe to the elements.

Per the AHJ, the only approved insulating process for metal sprinkler pipe is a thermal paint insulation.

I found the section for wrapped insulation that is allowed on non-metallic pipe by NFPA 13, but is there a section where wrapped insulation can be used on metal pipe?

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We have a building that is constructed. It has a very deep footing.

The contractor originally submitted an Ames In-Building Riser, but it's too deep for the in-building riser in the building's (essentially) existing condition.

They proposed using C900 to come under the footing, without a sleeve, going below the 12" footing and then stubbing up into the riser room without thrust blocks.

We have concerns about restraint and a change of direction underneath the foundation.

NFPA 13 applies and C900 is a permitted material, which is what the contractor has suggested makes it acceptable.

Is routing C900 under a building footing, changing direction, and then stubbing into the building acceptable?

NFPA 20 says that if the test header supply main is more than 15 feet from the fire pump, it must be increased one pipe size or hydraulically calculated based on 150 percent of the rated pump capacity.

What form does the hydraulic calculation take?

Are we trying to determine if the main can flow 150 percent of the pump rating without running out of pressure?

How low a pressure would be acceptable?

Is this a one time calculation to size the main or is this a calculation that must be performed during each annual fire pump test?

Thanks in advance.

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The installation contractor and I have had an argument about how sprinklers should be spaced and calculated in a 13R system.

I have argued that per NFPA 13R Section 7.1.1.3.1, we should calculate 3 sprinklers in the greatest hydraulic demand area. This area is furthest from the riser and the calculation permits 16x16-ft spacing for the area that has the most sprinklers.

Section 7.1.1.3.1:
For each of the following situations, the number of sprinklers in the design area shall be all of the sprinklers within a compartment, up to a maximum of four sprinklers, that require the greatest hydraulic demand:

The contractor wants to remove a sprinkler in a single room and move a sprinkler 10 feet off of the exterior wall, but in NFPA 13R makes no mention of a single sprinkler proof calculation that could justify such a move.

There is no mention of a single sprinkler calculation in NFPA 13R permitting a spacing of 20x20, and so all sprinklers on the project can be only 16x16 if the greatest hydraulic demand is permitting it.

In NFPA 13D, it makes no mention of a single sprinkler calculation either, but does refer to single sprinkler operations in A.10.1. I did not feel comfortable designing a sprinkler system that was not up to code standards and need an outside opinion on this matter. Thanks in advance.

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I am trying to figure out how to protect an existing building that has never had a sprinkler system.

The building peaks at 46'-5" and in that area you can only have a max height of 25'-0 in storage, due to operable cranes in the bay.

Additionally, the building is constructed using 12" purlins, so ESFR pendants are out unless we want to put them on return bends.

I am trying to give the owner as much storage space as possible, and commodities as they plan to rent the building out to tenants in the future. I have searched through CMSA, CMDA, ESFR and storage to find a situation that best describes it.

The issue I always come up on, is the distance from top of storage to ceiling. Every scenario I have looked at, we seem to exceed the 10' or 20' maximum distance.

Does anyone have some criteria they used that is close to the situation above?

Thanks in advance.

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We are a structural engineer currently work for an architect on a small assembly hall project; a wedding venue that will seat over 99, which will require sprinkler protection.

The roof structure will be wood scissors trusses, 5’-7” deep at the center – see below.

​I mentioned to the architect that they will have to protect the “attic” space also with sprinklers.

In response, the architect said the owners want to finish the ceiling and insulate the attic space.

Where is it written about the maximum cavity size without sprinklers? Is it any cavity?

If so possibly we fill the entire attic space, which is small because of the unique scissors trusses. I don’t think this would be economical or practical.

But, what would the cavity depth have to be (underside of roof deck to top of batt or blown insulation) so that sprinkler protection of that concealed combustible space is not required?

I assume if this space is not sprinkler protected that “attic” compartments would be required. Any guidance on this matter would be appreciated. Thank you.

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3M recently announced they will no longer manufacture NOVEC 1230 by end of 2025 due to the presence of PFAS (https://news.3m.com/2022-12-20-3M-to-Exit-PFAS-Manufacturing-by-the-End-of-2025).

Other similar agents, such as FM-200, have similar environmental concerns due to having HCFCs.

Does anyone know a chemical fire suppression agent that doesn't have CFC or PFAS issues?

I know there is a new NFPA standard (770) on hybrid systems and that the Victualic Vortex is one such system, but not sure what other alternatives are out on the market. Thanks in advance.

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I have a situation where I need to protect a modular home manufacturing facility.

It has a paint both that's self-contained with its own sprinkler hookups, all the regulars of a tiny home making shop basically. They will have rack storage of wood products up to 20' high and wanted the design to be such that they could move the storage rack locations in the future if they wished.

NFPA 13 (2016) A.5.4.2 gives a list of some Extra Hazard Group 2 occupancies and it specifically lists (4) Manufactured home or modular building assemblies (where finished enclosure is present and has combustible interiors) I had made the assumption that ESFR was a worst case, safe bet design for the entire facility due to the amount of water you get from heads opening up.

The contractor is concerned with how code says one thing in one place and something open to interpretation in another place. Section 8.4.6.6 says "ESFR sprinklers designed to meet any criteria in Chapter 12 through Chapter 20 shall be permitted to protect light and ordinary hazard applications."

That's fine, but I just see that as just a statement.

When you get to the requirements for Storage, Section 12.6.7.1 says the following: "ESFR sprinklers designed to meet any criteria in Chapter 12 or Chapter 14 through Chapter 20 shall be permitted to protect any of the following: (1) Light hazard occupancies (2) Ordinary hazard occupancies (3) Any storage arrangement in Chapter 13 referencing OH1, OH2, EH1, and EH2 design criteria"

Item 3 is where I want to make the argument that we can in fact use ESFR sprinklers in an Extra Hazard Group 2 scenario.

Can ESFR be used for an Extra Hazard Group 2 situation like this?

I need some expert opinions/interpretations. Thanks in advance.

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I'm a plan reviewer for a project that's coming into our area. We have a local gym/special amusement facility that has several foam pit areas.

What is an appropriate sprinkler design criteria for a foam pit?

The plans call for a 5-ft platform, which leads us to believe the pit is 5-ft or less in depth, but we're not sure about the building on the platform of other foam pads; so there's a chance this depth could exceed 5-ft when it's all said and done and measured with a tape.

Best I can relate to for this type of situation is in NFPA 13 2022 edition, Section 4.3.1.7.2.4, which references Table 4.3.1.7.1.1. Also, I've referenced IFC 3203.7.1 for classification.

Is there any other information that you can point me to for guidance?

If so, it would be greatly appreciated.

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For a fire pump subject to NFPA 20, I know that the suction side requires an eccentric reducer, but “can” one be put on the discharge side?

I have a situation where we are removing and replacing existing pumps where both the suction and discharge are at the same elevation, but the new pumps have the discharge about 2.5” lower than the suction.

I am trying to find a solution to resolve this. Thanks in advance.

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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!

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We have a situation where we'll have a piece of equipment in one control area that has a closed-use pipe arrangement with oxidizing gases that goes through different control areas. I've gotten conflicting feedback on this.

How do you figure the amount of "in-use" for each control area? 

Here's a sketch of the concept:

The equipment that is using the oxygen is on the fourth floor Control Area 2. The tanks that feed it are (2) 200 CF oxygen tanks that are in the second floor Control Area 1.

Which of the following two scenarios is the proper way to tally up the "in-use" quantity for the fourth floor Control Area 2 when comparing against the Maximum Allowable Quantities (MAQs)?

• Concept #1: The "in-use" amount is only the gas within the equipment itself, and only the gas within the piping to the extent of the control area wall.
• Concept #2: The "in-use" amount is all of the gas within the equipment itself, and all of the gas within all of the piping, and all of the gas within the (2) oxygen tanks which are actively hooked up to it.

 
My initial gut reaction was that the second option is correct, but now I’m not sure. My reasoning being that if there is an event in 4th floor control area 2 that causes a leak or something like that, it’s not going to just leak out what is physically within the control area… it’s going to leak out everything in all of the piping, all of the equipment, and all of the hooked up tanks. This is all presuming there are no safety devices to stop this from happening.

Assuming my initial gut reaction was correct, is there a way to limit the amount so that it stops at the control area wall?

As in: is there a safety device such as an automatic shutoff valve we can put at the wall such that in the event of a leak or other event, the automatic valve will shut off and then we only have to count the amount of gas between the equipment and the shutoff valve?

I’ve looked in the IBC and its commentary for more info, but couldn’t find anything helpful. I’ve also reached out to a number of different people and there seems to be a variety of different opinions on it.

Thanks in advance.

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It's already February! Here's our Top Ten Contributors for last month:

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.

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