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#154277 - 12/15/04 04:54 PM Fire sprinklers
drillman Offline

Registered: 03/24/03
Posts: 97
Loc: Somewhere in Texas
Anyone got any info on Fire sprinkler systems? I just had a two day training class at the jail where I work on how to shut them off and drain and replace heads.

I noticed they use "sprinkler" pipe. It looks like black pipe to me so whats different?

Are the threaded fittings different that plumbing or gas ones?

Any other general info would be nice.

And for those who wonder, yes sometimes inmates will break a sprinkler head.

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#154278 - 12/17/04 02:23 PM Re: Fire sprinklers
royta Offline

Registered: 09/03/04
Posts: 136
Loc: CA
I worked on my first fire sprinkler installation when I was 12, and worked every summer until the end of high school, adn then full time until about 20. My dad is a plumber/fire sprinkler contractor.

I haven't seen many, if any at all, sprinkler heads that weren't 1/2" or 3/4" NPT. The majority of the branch lines we installed were on SCH 40 Black, as opposed to galvanized, pipe. The majority of main runs are in SCH 10 pipe, assembled with roll groove "Victaulic" fittings. We plumbed and ran sprinklers in a motel, and the lines were CPVC, or Blazemaster pipe.

Who taught the training class? It must be a wet system in a warm weather climate. If it were a dry system, you'd be having to reset the dry valve and all that other fun stuff. A wet system in a cold climate requires an anti-freeze in the lines, to keep the pipe from freezing. Every year we had to test all of the wet systems in the county we lived in for proper freeze protection. If you have a head go off in an anti-freeze wet system, you'd be required to refill the system with an anti-freeze/water solution.

At about 22, I realized I didn't want to get dirty cutting and threading pipe, so my destiny of owning my dad's company disolved. I'm now an licensed EC, and struggling to start going at it full time. You can shoot me an email if you'd like.

#154279 - 12/18/04 01:23 PM Re: Fire sprinklers
Sir Arcsalot Offline

Registered: 11/17/03
Posts: 117
Loc: Lynden, Washington
Speaking of fire sprinklers, the modern fire sprinkler is really a great invention- ol' Hank Parmelee would be proud!

I've long been wondering why old-style aprinkler heads (pre-1953, I believe) are required in fur storage vaults. I know there was a study in 1947 on such- the only thing I could guess is that if fur fibers dislodged and gathered on the ceiling then perhaps a "flash fire" would occur and the old-style heads would in fact minimize this because of their spray pattern.

No, I've never been involved with NFPA 13 and fire sprinklers but it's something I was curious about.

(OOPS! Sorry for the threadjack, folks)

[This message has been edited by Sir Arcsalot (edited 12-20-2004).]
No wire bias here- I'm standing on neutral ground.

#154280 - 12/20/04 04:39 PM Re: Fire sprinklers
drillman Offline

Registered: 03/24/03
Posts: 97
Loc: Somewhere in Texas

where to begin..... this is a multi building jail facility. We have both wet, dry and pre action systems.

The person teaching the class is one of the deputies. He has a specific job which is to moniter and repair all the fire alarms, sprinkler systems and the like.

I am not a guard but part of the maintenace crew. We get training in fire sprinkler repair. Many times an inmate will throw something at the head and pop it. The guards will check and if there is no fire they will turn off the water and call us to fix it.

Some of you may be say this is against the law you got to have a license. We have permission from the fire marshall to replace broken heads, refill the system, and thats it. We cannot extend or modify the sprinkler system in any way. In fact we need to have a licensed sprinkler company do an inspection and pump test every year.

The main reason for this is simply the amount of false alarms we have. We cannot let the inmates out every time theres a false alarm.

#154281 - 12/30/04 06:49 PM Re: Fire sprinklers
John Steinke Offline

Registered: 04/03/01
Posts: 509
Loc: Reno,Nv., USA
The NFPA has a specific standard covering the instalation and maintenance of sprinkler systems.
Anything used with a sprinkler system must be rated for the use; that is, specifically tested and listed by UL, FM, etc. While the parts may look like ordinary plumbing pieces, they certainly cost more, and usually have the mark of the testing agency cast or stamped onto them.

In general, (there are some specialty applications) all sprinkler heads must pass the exact same tests- therefore, it is not critical that you stick with the same brand of head.
Places like Grainger, McMaster-Carr, and others sell repair kits that typically contain six heads and a wrench. Every floor or building is usually required to have one but I know prisons are different).
Rather than drain the entire system, there are carbon dioxide powered, or refrigerated, devices that are made to go on to a pipe and freeze a short section. This "plug" then allows you to work on one section, without draining the entire system.
To facilitate repair, you may replace the head while the water is flowing with a short nipple that has a valve on it; once in place, close the valve. Freeze the pipe upstream, replace the head, then let the plug melt. No need to drain everything.


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