Use Sprinklers In Lieu of 1-Hour Rated Glass?

5/8/2024

Can window sprinklers be used to protect internal glazing in partitions in lieu of fire rated glass partition?

The life safety engineer has requested to provide sprinklers on internal fully glazed partitions to save the cost of fire rated glazed partition. Not for the entire hospital, only some internal partitions in a hospital for glazing with 1-hour fire rated ones.

Although couldn't find anything in the NFPA 13 that support his request as I know this is valid only for atriums, am I right?

I appreciate the help and response as always.

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11 Comments

Anthony

5/8/2024 08:17:59 am

Window sprinklers and wall ratings are available in NFPA 12- 2016 see 8.15.26.

There are a whole bag full of special requirements around using window sprinklers but they sure are cheaper than rated glass.

Make sure you follow all the cut sheet rules; Reliable and Tyco have several options for you.

To be super clear this is not an atrium water curtain, this is a specially listed sprinkler.

Jack Smeck

5/8/2024 08:42:15 am

Hi there,

I had a similar case recently. You are correct, this allowance is for atriums only (see https://www.meyerfire.com/blog/windows-sprinklers-fire-ratings-part-i).

However, there are manufacturers that have tested a window-sprinkler assembly to ASTM E119--the same standard used for testing fire rated barriers. This "assembly" includes specifications for the window in addition to spacing/location of the window sprinklers.

Tyco is the manufacturer I'm most familiar with (https://www.tyco-fire.com/products-and-solutions/sprinklers-nozzles-and-accessories/special-application/cws-ws_fis/models-cws-and-ws-sprinklers). As mentioned in the datasheet, since this isn't prescribed in the IBC, it needs to be submitted as an alternate means. Good luck!

Todd E Wyatt

5/8/2024 08:43:35 am

Per the scoping Code (e.g. IBC-2021) there are (3) methods for determining the fire-resistance rating (FRR) of building elements, components or assemblies including FRR glazing :

1. 703.2.1 Tested Assemblies
2. 703.2.2 Analytical Methods
3. 703.2.3 Approved Alternate Method

Based on the 703.2, the “703.2.2 Analytical Methods” is to be used “WITHOUT the use of automatic sprinklers or any other fire suppression system being incorporated” so this option is out.

That leaves “703.2.1 Tested Assemblies” or “703.2.3 Approved Alternate Method”.

FRR glazing shall be “tested in accordance with ASTM E119 or UL 263 and complying with the requirements of Section 707.” Section 707 addresses “Fire Barriers”. The ASPS “deluge system” exception for the “enclosure of atriums” is prescribed in IBC-2021 404.6 (see References below) and permits this as a substitute for the required 1-Hour Fire Barrier (1FB) separation of an atrium from adjacent spaces IF the atrium’s glass wall forms a Smoke Partition and it meets the (3) conditions listed.

If the life safety engineer can provide a tested assembly that includes an automatic sprinkler system (ASPS) with glazing meeting the requirements of the required FRR assembly, the AHJ may permit it.

However, many AHJs will not approve the substitution of a required (non-active) FRR assembly (e.g. 1-Hour Fire Barriers w/Fire Glazing protecting an Interior Exit Stairway) with an “active system” such as an ASPS. ASPS are not always 100% effective and some AHJs may use the intent of “WITHOUT the use of automatic sprinklers or any other fire suppression system being incorporated” per “703.2.2 Analytical Methods” against the requirements of “703.2.1 Tested Assemblies.”

Todd E Wyatt

5/8/2024 08:44:02 am

REFERENCES
IBC-2021
Chapter 7 Fire and Smoke Protection Features
Section 703 Fire-Resistance Ratings and Fire Tests
703.2 Fire Resistance
The fire-resistance rating of building elements, components or assemblies shall be determined in accordance with Section 703.2.1 or 703.2.2 without the use of automatic sprinklers or any other fire suppression system being incorporated, or in accordance with Section 703.2.3.

703.2.1 Tested Assemblies
A fire-resistance rating of building elements, components or assemblies shall be determined by the test procedures set forth in ASTM E119 or UL 263. The fire-resistance rating of penetrations and fire-resistant joint systems shall be determined in accordance with Sections 714 and 715, respectively.
703.2.3 Approved Alternate Method
The fire resistance of building elements, components or assemblies not complying with Section 703.2.1 or 703.2.2 shall be permitted to be established by an alternative protection method in accordance with Section 104.11.

703.4 Fire-Resistance-Rated Glazing
Fire-resistance-rated glazing, when tested in accordance with ASTM E119 or UL 263 and complying with the requirements of Section 707, shall be permitted. Fire-resistance-rated glazing shall bear a label marked in accordance with Table 716.1(1) issued by an agency and shall be permanently identified on the glazing.

Chapter 4 Special Detailed Requirements Based on Occupancy and Use
Section 404 Atriums
404.6 Enclosure of Atriums
Atrium spaces shall be separated from adjacent spaces by a 1-hour fire barrier constructed in accordance with Section 707 or a horizontal assembly constructed in accordance with Section 711, or both.
Exceptions:
A fire barrier is not required where a glass wall forming a smoke partition is provided. The glass wall shall comply with all of the following:
1. Automatic sprinklers are provided along both sides of the separation wall and doors, or on the room side only if there is not a walkway on the atrium side. The sprinklers shall be located between 4 inches and 12 inches (102 mm and 305 mm) away from the glass and at intervals along the glass not greater than 6 feet (1829 mm). The sprinkler system shall be designed so that the entire surface of the glass is wet upon activation of the sprinkler system without obstruction;
2. The glass wall shall be installed in a gasketed frame in a manner that the framing system deflects without breaking (loading) the glass before the sprinkler system operates; and
3. Where glass doors are provided in the glass wall, they shall be either self-closing or automatic-closing.

Glenn Berger

5/8/2024 08:59:33 am

This is definitely accepted practice. You might be able to find some documentation in openings in rated construction and similar discussions.

Steve Cooper

5/8/2024 09:20:26 am

Check out ESR-2397. It is an evaluation report for two Tyco window sprinklers. Goes over how and when to use them. It also sites all the codes it is compliant with. It has the hydraulic requirements as well.

Jerry Clark

5/8/2024 09:26:44 am

Yes, you can. Now allowed in various applications, not just atriums. We employed this method of protection in 2-hour egress corridors for a large Google project:

https://icc-es.org/report-listing/esr-2397/

Brett

5/8/2024 09:58:44 am

Yes, you may use sprinklers to protect glass (glazing). There are a few companies who make window sprinklers. You will also find standard sprinklers used in older installations. There is also a Meyer Fire post on this: https://www.meyerfire.com/blog/windows-sprinklers-fire-ratings-part-i

NFPA 13 [2022 ed.]
9.3.15* Sprinkler-Protected Glazing.
Where sprinklers are used in combination with glazing as an alternative to a required fire-rated wall or window assembly, the sprinkler-protected assembly shall comply with the following:
(1) Sprinklers shall be listed as specific application window sprinklers unless the standard spray sprinklers are specifically permitted by the building code.
(2) Sprinklers shall be supplied by a wet pipe system.
(3) Glazing shall be heat-strengthened, tempered, or glass ceramic and shall be fixed.
(4) Where the assembly is required to be protected from both sides, sprinklers shall be installed on both sides of the glazing.
(5) The use of sprinkler-protected glazing shall be limited to non-load-bearing walls.
(6) The glazed assembly shall not have any horizontal members that would interfere with uniform distribution of water over the surface of the glazing, and there shall be no obstructions between sprinklers and glazing that would obstruct water distribution.
(7) The water supply duration for the design area that includes the window sprinklers shall not be less than the required rating of the assembly

19.3.5 Sprinkler-Protected Glazing.
Where the sprinkler-protected glazing is required to comply with 9.3.15, the water supply duration for the design area that includes the window sprinklers shall be not less than the required rating of the assembly.

19.3.5.1 For sprinkler-protected glazing, the number of sprinklers calculated for the glazing shall be the number in the length corresponding to the length parallel to the branch lines in the area determined by 28.2.4.2.

19.3.5.2 If a single fire can be expected to operate sprinklers for the sprinkler-protected glazing and within the design area of a hydraulically calculated system, the water supply to the sprinkler-protected glazing shall be added to the water demand of the hydraulic calculations and shall be balanced to the calculated area demand.

19.3.5.3 Hydraulic design calculations shall include a design area selected to include ceiling sprinklers adjacent to the sprinkler-protected glazing.

Dave

5/8/2024 10:42:23 am

Reliable has a good, archived webcast from Dec. 2020
https://youtu.be/VEX-pa9h4DQ?si=UuBdTVqET5y0nEM_

Franck

5/8/2024 12:54:08 pm

I would say yes if the windows are there and you need 1h rating.
I would say no for a new project, simply because a 1h rated wall, door or window is a passive protection. It works even if your fire protection system is impaired.
From an insurance point of view (property damage) it may make a big difference.
So for a new project, provide 1 h rated glass windows.

cathy

5/9/2024 10:48:33 pm

1, TYCO TY3388 window sprikler.
2, If there is pony wall below the glazing, that portion still needs to be fire rated.
3, I remembered the test was done for a glazing up to 4.2m high.
4, horizontal mullion would be an obstacle to change direction of the spray. Depends on the size and shape of the mullion, a second row of window sprinkler under the mullion may be needed.

Use Sprinklers In Lieu of 1-Hour Rated Glass?

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