NFPA 13, sprinkler heads and square footage

[nemptygarden]

Under NFPA 13 are there specific square footage requirements per sprinkler heads? I work in a hospital environemnt and the maintenance department is doing some remodeling in one of our buildings. One rooms has only one sprinkler head and is rather large. The buildings were built in 1968. The sprinkler system is dry.

 

[stookeyfpe]

Yes. It is dependant on the hazard classification of the room, the type of ceiling, and if the system is hydraulically calculated or designed using the pipe schedule method. It would also be dependant on the presence of obstructions.

For light hazard occupancies, the protection area varies from 120 to 225 square feet for each sprinkler. For ordinary hazard occupancies the maximum protection area is 130 square feet. The maximum sprinkler spacing for both light and ordinary hazard occupancies is 15 feet.

For extra hazard occupancies the answer is a tad more difficult.

So what is the room used for and its construction type? With more information we may be able to help you.

See Section 8.6.2.2.1 of the 2002 edition of NFPA 13.

 

[nemptygarden]

stokefpe, the room will be a chart room where the nurses and doctors will work. It will house a copier, fax and other small business machines. there are no obstrucitons in the room, the ceiling is popcorn treatd gypsm board. it leads into a dayroom where patients will be watching televison etc. The walls of the room are fire rated gypsm board.

 

[stookeyfpe]

I would classify the room as Light Hazard. Given the building's age I will assume the sprinkler system was designed using the pipe schedule method.

As a result the area of protection for standard spray sprinklers (either pendant or upright) is 200 square feet. The maximum spacing between sprinklers is 15 feet.

 

[safetydan]

Doctors and nurses together in the same room only a light hazard?? I think the steam coming out of some of the nurses' ears would be enough to set off a few heads.

 

[crazzy111s]

we are installing a computer room, we are considering raising the head temperature to protect the equiptment from lower temperature fire sprayings. i have been told this is against code what are some possible solutions.

 

[twd22285]

IF your looking to protect from fire but not ruin your computers a chemical system might be an option. I don't know much about am, but the idea is that you can control the fire through a dry chemical charged by co2 or some sort of dry charge. never designed one and i am new to the fire sprinkler industry but i've heard of a chemical system being used in place of a wet system for computer rooms

 

[cdafd]

crazzy111s

what temp head do you want to use??

what is fire sprayings??


do not have a copy of nfpa 13 in front of me but look at what level of head you can have in that hazard and than look at the temp chart for that and just max out the head in that temp range.

so at what point of the burning computer equipment do you want the head to activate to possibly save the rest of the equipment?????

 

[LCREP]

Crazzy

If it gets hot enough to set off a sprinkler head, regardless of the temperature rating, the computer room will have significant damage. Consider a quick response, 135F sprinkler for faster response. The best protection is a gas suppression system such as FM200 AND sprinkler protection. Down side of a gas system, IF a door is open, or a vent does not close, the gas will escape and the fire will not be controlled. At the very least have a fire detection system, smoke detectors, and sprinklers.

Tom

 

[SCEngr1]

I have a question for a different application:

For a 10'x12' paint mixing room (closed cap system), can we provide the one-hour fire barrier between this room and the retail space in the rest of the store WITHOUT an automatic sprinkler system?

Also, how do you determine the "Fire Hazard Classification"?

 

[stookeyfpe]

Start a new thread.

 

[sfallows]

go with pre-action system no expensive cost of maintaining a chemical system, this has become good practice as hardware cost for computers has dropped so unless you have OEM hardware a pre-action system would allow for any potential accidental discharge.

additionally your computer equipment should not be operating in an environment that is hot enought to set off a quick response ordinary temp. head