NFPA 13 & 13R Sidewall sprinklers and light fixtures.

[carlosgw]

In NFPA 13R there is a requirement to not install a sidewall sprinkler with-in 5 feet of a light fixture.
In most residential projects the light fixture is a ceiling mounted round globe maybe 12" diameter for example. In some cases like hallways and kitchens there is no way to get a 5 foot clearance. If sprinklers are installed on either side of the fixture it does not seem that the fixture would protect the opposite sprinkler.
IF using NFPA 13, the clearance is 8 feet so the situation is worse.
Am I misinterpreting something?

 

[cdafd]

Do you mind giving the sections you are reading

 

[carlosgw]

NFPA 13R 6.8.1.5.3.3

 

[cdafd]

May or maynot answer your question , have not read it;;

http://www.nfpa.org/assets/files/PD...sidential_Sprinklers...-V.Valentine_paper.pdf

That section does throw you to 6.8.1.5.3.5 if you can meet that

Maybe because of the different spray pattern in 13r?

 

[TravisMack]

What year of the standard are you referencing?

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[carlosgw]

2007

 

[cdafd]

6.8.1.5.3.3 Sidewall Sprinklers.

(A) Sidewall sprinklers shall be located at least 5 ft (1.52 m) from obstructions such as ceiling fans and light fixtures unless the requirements of 6.8.1.5.3.5 are met.



(B) The distance shall be measured from the center of the sprinkler to the center of the obstruction.



(C) Where the sprinkler cannot be located 5 ft (1.52 m) from the obstruction (as measured to the center of the obstruction), an additional sprinkler shall be installed on the other side of the obstruction.



THERE is this provision that can be used::::::


(D) Where the area of the fan blades encompasses more than 50 percent of the area of the plan view, the sprinkler shall be installed in accordance with 6.8.1.5.3.5.

 

[carlosgw]

Let's say you have a 9X9 room with a small (12" dia 8" deep) light in the middle. Two sidewall sprinklers on opposite sides of the light fixture (assume ceiling sprinklers are not an option). The light fixture is supposed to protect the sprinkler from the spray from the opposite sprinkler?

 

[cdafd]

Depending on the head used you may only need one head

Once again if you can meet:::: you may be alright


THERE is this provision that can be used::::::


(D)   Where the area of the fan blades encompasses more than 50 percent of the area of the plan view, the sprinkler shall be installed in accordance with 6.8.1.5.3.5.

 

[TyphoonK]

carlosgw,


"Let's say you have a 9X9 room with a small (12" dia 8" deep) light in the middle. Two sidewall sprinklers on opposite sides of the light fixture (assume ceiling sprinklers are not an option)"

See product data and listing of sidewall sprinklers. Some sidewall sprinklers are listed to be located 6"-12" or 12"-18" below the ceiling.


"The light fixture is supposed to protect the sprinkler from the spray from the opposite sprinkler?"

For obstructions less than 4 feet in width, sprinklers spaced on opposite sides of obstructions shall be spaced not less than 1/2 the allowable distance between sprinklers.

The examples have been using a surface mounted light fixture, but if the light fixture was a pendant then the three times rule would apply.