While all of that is true, there are times when you just cannot provide a wet 
standpipe such as in this case.

However, from some discussions I’ve had, they would not charge into a fire 
until flow is established at the riser.


Craig L. Prahl
Fire Protection Group Lead/SME
CH2M
200 Verdae Blvd.
Greenville, SC  29607
Direct - 864.920.7540
Fax - 864.920.7129
CH2MHILL Extension  77540
[email protected]


From: Sprinklerforum [mailto:[email protected]] On 
Behalf Of Bruce Verhei
Sent: Wednesday, August 30, 2017 2:09 PM
To: [email protected]
Subject: Re: Standpipe question [EXTERNAL]

The big advantage of wet pipe systems is not just the delay waiting for water 
at the nozzle as air, compressed by the water, blows off. It is all the junk in 
the system clogs up the nozzle. This can be so extensive that flow almost 
stops. Having a Dodge Charger Hotwheel in your nozzle, backed up by cigarette 
butts does not make your spray pattern more effective.

Or the system may open to the atmosphere somewhere. Wet systems leak right away 
when compromised.
So how far does the hose team advance the dry hose line towards the fire before 
they charge it? How much confidence do they have that a decent, protective, 
hose stream is about to derive?


Best

Bruce Verhei

On Aug 30, 2017, at 09:45, Steve Leyton 
<[email protected]<mailto:[email protected]>> wrote:
From my perspective, the intent of the building code allowance for dry 
standpipes is to accommodate a broad range of exposures to freezing.  It would 
be silly to run wet pipe through an area subject to freezing in order to supply 
a single floor’s hose connections, and you’d have to valve the roof manifold(s) 
to hold back water from exposure as well.   Since I don’t live in a place 
that’s subject to freezing, I’ve never personally had to address this 
condition, but if I did I’d run a manual dry all the way.

The foregoing is my opinion only and is not intended to represent the NFPA 14 
Technical Committee, nor serve as an interpretation of the standard.

Steve Leyton
Protection Design & Consulting
San Diego, CA




From: Sprinklerforum [mailto:[email protected]] On 
Behalf Of [email protected]<mailto:[email protected]>
Sent: Wednesday, August 30, 2017 6:16 AM
To: 
[email protected]<mailto:[email protected]>
Subject: Standpipe question

(3) sty sprinklered building
           1st and 2nd floor are un-heated parking garage
           3rd floor is office

I'm not sure if a manual dry can still be used if top floor is heated
 IBC 905.8 permits dry stdp in areas subject to freezing in accordance with 
nfpa 14
 NFPa 14 , 2003 5.4.1.4  says CL I systems shall be wet except where subject to 
freezing


_______________________________________________
Sprinklerforum mailing list
[email protected]<mailto:[email protected]>
http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
_______________________________________________
Sprinklerforum mailing list
[email protected]
http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org

Reply via email to