With the use of CPVC, what are the limits to how much can be exposed?

I had thought that we needed to have all of the pipe concealed, and I can't see in code how this is addressed.

We have a project with a temperature-controlled and insulated attic (the mechanical engineer has confirmed it will be kept above 40 degrees F year-round) in a warm climate. This is in an NFPA 13R apartment building.

Is CPVC allowed to be run exposed through the combustible attic space?

The attic is not sprinkler protected (NFPA 13R system, 3-story, apartments, smaller-sized project). Thanks in advance.

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An engineering firm has insisted that a waterflow activation shutdown the HVAC system and cited NFPA 90A: A.6.4.3.

A.6.4.3 Where automatic water sprinklers are provided and zoned to coordinate with the HVAC zones, their water flow switches should initiate devices for the functions described in Chapter 6.

Each floor of the building has one HVAC zone and one sprinkler zone (floor control valves).

The HVAC system has the appropriate duct detectors and functions.

The only instance I have experienced using flow switches for HVAC control is when there is no automatic smoke detection and the flow switch is used to start the smoke control system for that zone.

What are your thoughts?

Is a waterflow switch required to shutdown an HVAC system on this premise?

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Can HDPE ISO 4427, PE100 SDR 9 PE be used for underground water service pipe (dedicated for fire water), even though it carries no FM Approval?

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Does a correctional occupancy type imply secure ceilings are required?

NFPA 5000 could be interpreted as such, but as we know, it's more about the construction of the building. There is a ceilings section though so I'm unsure.

If plans called for an institutional sprinkler and secure ceilings but the owner/government changes their mind and installs standard sprinklers, is there any issue or repercussion?

Look forward to your interpretations. Thanks.

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I am currently working with a few artists that want to build an installation in the lobby of a high-rise office building.

Their design includes hanging acrylic bats independently hung from wires from the ceiling at varying heights to represent a bat swarm. What started as “a couple hundred bats, 6-8 inches in size, spaced evenly throughout the lobby” has turned into 1,300 bats, up to 12 inches wide, in a fairly dense swarm.

The artists and interior designers submitted this design to the AHJ without providing a final design or correspondence and were rejected (no surprise.) The rejection was based on the swarm obstructed both by being within 2 feet of the head, and the density of the bats.

Additionally they are worried about the flammability of the bats and want them tested per NFPA 289 to make sure the amount of acrylic has a heat release rate of less than 100 KW.

My questions here are two-fold:

1) How would one properly protect, or space these bats, so that sprinkler protection is not an issue?

At what density would hanging items like these turn into an obstruction, and once they are considered an obstruction, would the only way to solve the issue be to sprinkler both above and below the swarm?

2) Has anyone ever worked with NFPA 289?

I have been looking for information on heat release rate of acrylic or any plastic in general, who would test items to the NFPA 289 standard?

Or is there any information on how to properly categorize this hazard and determine if the heat release rate is less than 100 KW?

Looking forward to any thoughts. Thanks.

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Thanks for answering my previous questions; I have another one today.

Is the life safety electrical demand on the generator, for the electrical engineer, based on the normal-duty load (346 bhp), motor load (500 bhp), or the maximum locked-rotor road (572 bhp)?

Is there a governing standard that dictates this (IFC/NFPA 20/NFPA 70)?

We have a 2,000 gpm, 185 psi rated electric fire pump. Thanks in advance.

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​Here's a twist on the 9/28/2021 post regarding 4 or 8 sprinkler residential calcs (link here):

​Given an NFPA 13-2016 fully sprinklered wood framed apartment project, with residential sprinklers, and unsprinklered combustible concealed TJI spaces between floors, per Section 8.15.1.2.6 similar to this system:

Spaces between joists are blocked into 160 cubic feet using the same TJI material.

Spaces are not firestopped with a minimum ½” drywall on the sides of certain TJI’s into 160 cubic foot spaces.

Since the 2013 NFPA-13 came out, my understanding has been that unless we were to install ½” gypsum on the side of every few TJI’s to subdivide into 160 cubic foot spaces, an 8-sprinkler calculation is required in the occupied spaces above and below this assembly.

Some have argued that since it’s a 1-hour assembly, a 4 sprinkler calculation is fine since that’s greater than a 30 minute barrier (light hazard water supply duration) as discussed in 11.2.3.1.5.1 (B). However, Annex A11.2.3.1.5.1 seems support the 8 sprinkler calculation because the assembly is the qualifying non-sprinklered area.

However, in the above example, a portion of that assembly in itself provides a 30 minute barrier. It’s a 1 hour rated assembly but In this case, the bottom is 2 layers of Type X which in itself is greater than a 30 minute barrier.

I’m guessing that the top with tongue and groove sheeting and 1” of gypsum would also provide at least a 30 minute barrier.

Would the NFPA 13 sprinklered dwelling spaces above and below this (allowed) non-sprinklered floor/ceiling space require a 4 or 8 sprinkler calculation?

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Can "open parking garages" be located below high rise buildings?

If so, can the standpipes for the parking garage be manual dry and can sprinklers be omitted in the portion of the building considered an open-garage expect for the level directly below the high-rise occupancy?

Trying to get some big-picture understanding here, thanks.

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We have very deep beam glue-laminated timber construction that just has the laminated wood exposed to below.

The beams are very deep; 2'-9" deep. These form bays that are 13'-9" x 13'-9", many with smooth ceilings. The area below is light hazard.

Can sidewall sprinklers be used up in these coffered areas?

Can non-residential sprinklers be used in a NFPA 13R design?

NFPA 13R lists that residential sprinklers are permitted for use but does not list they are required to be used.

My understanding is that sprinklers used in NFPA 13 for light hazard would exceed or meet sprinkler requirements within NFPA 13R

On this premise, would installing a sprinkler for light hazard occupancy be exceeding NFPA 13R minimums, and thus be acceptable?

We have a dry sprinkler system we are installing in a small existing dormitory built with combustible construction.

We are using a NFPA 13R design approach which avoids sprinklering the attic space, with local AHJ approval. We need to have concealed sprinklers under request of the owner based on the occupancy, but there are not residential concealed dry pendent sprinklers, and the contractor is pushing to install recessed dry residential sprinklers.

Thanks in advance.

​

Does FM Global design criteria weigh in on whether skylights require protection?

Do they simply adopt the same provisions in NFPA 13 in this regard? Or is there some devation?

I can't see any allowance for omission of sprinkler protection for skylights in Data Sheet 2-0.

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We have an internal discussion agreeing to disagree, regarding protection of a non-flammable powder coating booth in a tenant building with existing sprinkler system.

We are installing a dedicated auxiliary wet system dropping down with a loop to pick up a valve for an OHII system per NFPA 33 (2016) 9.4.2 (2). Protection Automatic Systems - Powder coating operations.

First Question - Section 9.2.1 and 9.7.1 indicates there must be a means to accomplish all of the following:

1. (1) Activate a local alarm in the vicinity of the of the spraying operation
   
2. (2) Transmit an alarm signal to the facility fire alarm system if such is provided. "In this case yes existing alarm, with existing overhead sprinkler system"
   
3. (3) Shut down the coating material delivery system
   
4. (4) Shut down all spray application operations
   
5. (5) Stop any conveyors into and out of the spray area.
   

To accomplish the above one side of the office believes a flow switch is needed to accomplish this requirement with double set of contacts.

The other side of the office contends the existing alarm system is adequate enough and if activated the main flow switch will accomplish this. The argument is if this is a dedicated auxiliary system with potential multiple tenants and requires the water flow switch for the Aux Booth System to activate per 9.2.1 and 9.7.1 as noted.

Is this correct?

Question 2 - if a flow switch is required to accomplish 9.2.1 there shall be a means to test with inspector's test connection or a riser manifold with a combination inspector's test & drain at the new dedicated auxiliary riser. Is that correct?

There needs to be an indicating control valve per 9.4.5 operable from floor level for the Aux. Booth System.

Question 3 - can the valve be chained and locked open or does this control valve need electrically supervised open.?

Does there need to be a main drain for this auxiliary system?

I think everyone can follow the arguments so would appreciate some responses. Much appreciated.

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Is the minimum length  for a remote area determined by the original Density/Area (such as 1,500 sqft so it would be 46.5 ft), or is it based on a modified/adjusted area (such as 900 sqft = 36 ft).

After doing this for years, I was trained and always took is as a given that we use the length based on the original area. I cannot seem to find an actual reference backing this up.

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When calculating the number of operating sprinklers in a design area for a hydraulic calculation and where we have 2 levels of protection, do we include:

a) Both those sprinklers in the void and below the suspended ceiling in the design area;
b) Just those sprinklers in the void;
c) Just those sprinklers below the ceiling, or 
d) 50% of each?

​Any responses really appreciated.

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We have a 3-story building using machine roomless elevators (MRL).

I have an inspector asking for a smoke detector at the top of an elevator shaft even though there is no sprinkler at the top of the shaft.

There are roomless machine rooms on the first/ground floor lowest level. We installed smoke detectors in each of these roomless machine rooms putting the smoke/heat detector as close to the object it is protecting. There is no ceiling for these.

The inspector says he wants the smoke at the top of the shaft because of the machine room at the bottom floor and says the smoke will rise and we need the detector at the top of the shaft.

I wrote him a book report that NFPA 72 allows for smoke detectors to be installed close the object they are protecting.

There is a sprinkler in the pit and we have a heat next to it within 24 inches. I really think that the heat in the pit should generate a recall to the alternate level and they have us shunt tripping it?

Some details on the equipment location: the machinery is on the lowest-level inside the shaft. It is accessible by a man door from the side of the shaft.

Because of the machine being inside the shaft, is a smoke detector required at the top of the shaft?

The inspector is asking for the smoke detectors at the top of the shaft because the Machine room is in the shaft at the 1st floor. He says there is no ceiling in the machine room so he wants the smoke detector at the top of the shaft. 

Thanks in advance.

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We have a job that is a non-conditioned, pre-engineered metal building that serves as essentially a shipping hub for small parts.

There are approximately 34 roll back overhead doors, half on one side of the building, half on the other.

We live in an area where freezing happens every year, and the coldest temperature recorded during each year averages 4.6 degrees from 2021 to 1948.

The doors' tracks are installed at approximately 11'-0" AFF and the door opening is approximately 9'-6" tall. The doors are approximately 10' wide and equally spaced down the building in the 25' bays.

The sprinkler system inside the building will be a dry system due to the fact it is not a heated building but we will need sprinkler protection underneath the roll back doors. I think technically speaking the code would allow Option A; a single drop to feed two HSW heads with a 1" valve for drainage per 8.16.2.5.3.2 and 8.16.2.5.3.5 (2016 NFPA13).

But this would mean the owner is responsible for draining approximately 17 drains every year that are not even installed with drum drip assemblies, so tripping a system and/or yearly freeze ups could be a very real possibility.

Do you guys believe this would even technically be a code accepted method of protecting under these doors from a dry system in a building with no heat?

​Option A:​

When a building is 84-feet from an existing public fire hydrant located across a 2-lane 45mph roadway, can we assume it is standard practice to use it in an event of a fire?

Or would the owner be required to add a personal-use fire hydrant or water storage device on their side of the road?

In the latter case, how far would the fire hydrant have to be placed from the building?​

Thanks in advance.

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I am overseeing an NFPA 101, Chapter 43 reconstruction project in an existing storage occupancy that is changing to an industrial/high hazard occupancy.

I am trying to coordinate the means of egress during construction.

Other parts of the building are currently occupied and the new area is less than 50% of the building.

Section 43.7.2.3 requires that the area comply with the applicable new construction chapters of the occupancy. The hazard category per table 43.7.3 leads me to believe this would be a hazard category 1.

The question is: when is the construction area considered to be high hazard?

The contents of the hazardous occupancy will not be present through the entirety of the construction and will only be put in place after the space is ready to be occupied and compliant with all means of egress requirements. During construction, the "high hazard contents room" is just a small room with nothing located inside.

Even with no high hazard contents present until the space is ready to be occupied, does it need to meet the egress requirements of new industrial/high hazard or can it meet the egress requirements of existing for storage?

Thanks.

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I had always been taught that we do not allow more than one fire alarm system within the same building.

Does anyone know where that might come from (NFPA 72 or International Fire Code)?

Do you allow a Dedicated Function (sprinkler monitoring system) in addition to a fire alarm system, which are separate?

We have a multi-tenant strip shopping center, where developers used to build the shell with sprinkler and a sprinkler monitoring system, but a tenant like a restaurant might come in later to build out and need to put in a fire alarm system.

Thanks in advance.

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I have a new construction 5-story residential (dormitory) being constructed under UFC.

The architect inquired if lobbies need to be provided for the elevators, and, if not, do smoke protection (draft-curtains) need to be provided?

My immediate thought was of course, something needs to be provided. However, when I follow the code track of NFPA 101, it is not exactly clear in comparison to IBC.

The IBC is very clear, Section 3006 regarding the protection of hoistway openings.

Without going through the entire NFPA 101 code-track here, we end up back at NFPA 101 Chapter 8. Section 8.5.3 states a fire barrier can be used as a smoke barrier, provided it meets the requirements of Section 8.5. Hoistway openings, specifically elevator doors are not specifically mentioned in NFPA 101 Section 8.5. The only thing I can point to is Section 8.5.2 Continuity and Section 8.3.5.2 Joint Systems for Fire Barriers.

Other items: The hoistway is to be protected with a 2-hour fire rating, which requires the elevator door to be 1.5 hour rated (Section 8.6.5), and the building is protected throughout with automatic fire sprinklers, including the elevator shaft.

By definition, the building is not considered a high-rise. The hoistway height is ~57 feet.

​What are everyone's thoughts on this?

Thanks in advance.

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Since sidewall sprinklers must be installed below smooth, flat ceilings, when I am confronted by beams installed perpendicular to the wall in which sidewall sprinklers are installed, I always install sidewalls below the smooth flat ceiling of each beam pocket.

My challenger suggests that if the "Obstruction Along Wall" rules of NFPA 13 Figs. 10.3.6.1.4 (2019 ed.) / 8.7.5.1.4 (2016 ed.) for standard spray sidewalls is met* then you can "skip" a beam pocket if the overall spacing and coverage is met.

Can you skip a beam pocket with a sidewall?

My opinion is that these are not intended for continuous obstructions such as beams, which adversely affect heat collection.

Y'all on my side?

*or the relevant figures for extended coverage sidewalls, or via the MeyerFire Sprinkler Obstruction Tool are met

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Thanks to everyone for another outstanding month on the forum, and a shout out to our top ten forum contributors for February 2023 as well!

Where does - or does - NFPA 13 and NFPA 13D (2022 Edition) say that hydraulic calculations should be run from the most remote sprinkler to the water supply?

Apparently some hydraulic calculation programs print out the results backwards, which makes them harder to follow.

Thanks in advance.

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How would you typically access a smoke detector at the top of an elevator shaft to change a battery or test it?

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