About those "Fire Flows" 1

[SprinklerDesigner2]

Before I get beat up I want to say I recognize this work belongs to the professional engineers.

I received a fax from a Florida developer putting together a 3 story motel project that we'll get if it goes. Included was a request from the planning commission for "ISO Fire Flow Report" along with a flow test from the city engineers office indicating 50 static, 20 residual @ 20 psi.

I replied saying the water supply looked OK for the sprinkler (NFPA 13R) but for the fire flow report he needed to obtain the services of a professional engineer licensed in the state of Florida. To cover my rear I told him once the report was done I could tell him for sure if the supply was adequate or not.

At ths stage, total lack of drawings or specsifications, I can even be sure if an NFPA #13R system would be acceptable and a full 13 system would be a tough one given the water supply.

I think they're just getting into the project and shopping around for some cheap (free) information.

I don't want to know how to do one but I would like to know what it is and a few of the primary factors that go into putting a fire flow report together. I got a feeling it's about how much water is needed in an area adjusting for a myriad of factors like construction type, lot lines, other buildings etc but that's just my guess.

I would like to know enough about this to at least know what it is so I don't look like a dummy.

So if any of you PE types have a couple minutes, in a paragraph or two, what is an ISO Fire Flow Report?

 

[SprinklerDesigner2]

I wish this had an edit function.

That flow test was 50 static, 20 residual @ 750 gpm.

 

[stookeyfpe]

It's Florida. ISO is Insurance Services Offices and they have developed criteria for the required fire flow for a building based on its construction type, percentage of building openings that are protected or unprotected and proximity to exposure buildings. I recall ISO gives credit for a sprinklered building but I'm not sure if the credits are adjusted based on a 13 versus 13R system.

Essentially you would calculate your available fire flow at 20 PSI and compare it to the calculated fire flow using the ISO methodology, while also reducing it based on the installation of an automatic sprinkler system.

Static P = 50 psig; Residual P = 20 psig; Q = 750 GPM? That's one pathetic water supply.

 

[SprinklerDesigner2]

Thanks Stookey, that's the kind of answer I was hoping to get.

"Static P = 50 psig; Residual P = 20 psig; Q = 750 GPM? That's one pathetic water supply."

No kidding.

Tack on 3 floors, a 5 psi safety factor, sidewall sprinklers with a 20 ft. throw with an RPZ and there isn't much left to work with.

From what I am hearing planning boards or building departments in Florida can turn projects down if they don't meet the ISO criteria.

 

[jgailla]

I don't know about interior requirements, but most of the jurisdictions around here require a 1,500 gpm hydrant flow at 20 psi for this type construction. You might want to get with the civil engineer and see what they'll be required to do. We have had agencies relax the requirement a little, but not by half. The developer may be required to install additional infrastructure.

 

[SprinklerDesigner2]

Any of you Florida PE's want a referral?

Owner asked me to try to find someone.

 

[stookeyfpe]

SD2

A guy I highly respect is Tom Gardner with Schirmer Engineering in Atlanta. He does a lot of work in Florida and has a Florida P.E.

He'll treat you right.

 

[DonPhillips]

I used to know a Tom Gardner back in the late 80's. He worked for Turner Construction in Columbus, OH and later moved to Cleveland. Same guy, perhaps?


Don Phillips

http://worthingtonengineering.com

 

[stookeyfpe]

Nope. My Tom has only worked for the major FP engineering firms. He started in DC and worked his way up and down the East Coast.

I have a high degree of respect for my Tom - he's a solid FPE and I almost went to work for him. I hope I didn't miss an opportunity to learn from a really smart engineer. I just couldn't make the move to Atlanta (being a grumpy, hard headed Texan).

 

[RWF7437]

"I received a fax from a Florida developer putting together a 3 story motel project that we'll get if it goes. Included was a request from the planning commission for "ISO Fire Flow Report" along with a flow test from the city engineers office indicating 50 static, 20 residual @ 20 psi."

This request is asking for two different things.

The flow test report is simply a report of a hydrant test on one or more particular hydrants in the public water system. It usually reports the static pressure, in psi, the pitot gage reading and the measured flow in gpm based on that gage reading. With this information one can then calculate the probable available flow at any other pressure, such as the 20 psi most often specified.

A full ISO Report is a report of a comprehensive field and record survey of both the Fire Department and the water system(s) used in a community. It takes into account many factors such as; response time, available equipment, reliability of equopment, training, hydrant flow test results, etc. etc.

The ISO Report is used to classify the community's fire loss risk. ISO works for insurance companies so "risk" and "loss" are four letter words to their employers. The water system accounts for about 1/3 of the final classification of the community. The Class of the community is used to set fire insurance rates for all properties in the community; but especially residential properties.

If there is an ISO Report it is a public record and should be available at City Hall, the Fire Chief's office or maybe even the City Library.

good luck

 

[SprinklerDesigner2]

RWF7437,

I appreciate the input I try to learn something new everyday and usually end up learning more.

But that is Professinal Engineer stuff and I am just a sprinkler systems tech so I'm not paid enough to go there.

Seriously, if I read it I would probably understand most of it but wouldn't have a clue as to what to do with it.

 

[Bhhowie]

http://www.isomitigation.com/downloads/ppc3001.pdf

here is a link to how to determine needed fire flows, this will tell you how very deficient the water supply is in the area.