Ron. With a city supply we calc the fire flow separate from the sprinkler demand. I don't see why it would be any different with a tank. The onsite underground would not be sized to flow both simultaneously so I don't see why the tank would be sized for both.
Ron Fletcher Aero Automatic Sprinkler 21605 N. Central Ave Phoenix, AZ 85024 P: 623.580.7836 F: 623.434.3420 C: 602.763.4160 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ron Greenman Sent: Thursday, September 03, 2009 12:57 PM To: [email protected] Subject: Re: Fire Flow The reduction has already been approved. The fire flow demand is to supply a hydrant on the property. My question is (and no fire marshal to ask today),is the sprinkler demand included or need to be added? This tank supplies all fire water needs (no jokes-I know what you're all thinking) for this property. On Thu, Sep 3, 2009 at 12:50 PM, <[email protected]> wrote: > If you're talking about the fire flows referenced in the IFC, Appendix B, > this seems to be an AHJ or IU call. For the most part when the building is > fully sprinklered only the sprinkler system demand and hose stream demands > are used for water tank sizing. I've not had one AHJ or IU apply the fire > flow section of the IFC to the water supply when those conditions exist. Now > when a building is not protected I have had this section of the IFC applied. > However note that this section is not mandatory and is not a part of the > actual Code. See wording at the top of the first page. So it requires > clarification from the AHJ and/or IU as to what is applicable. But if there > is no direction we use it as the basis. > > Also note that the 75% reduction is "up to 75%" and "as approved", so it's > not an automatic reduction. > > > Craig L. Prahl, CET > Fire Protection Specialist > Mechanical Department > CH2MHILL > Lockwood Greene > 1500 International Drive > PO Box 491, Spartanburg, SC 29304-0491 > Direct - 864.599.4102 > Fax - 864.599.8439 > [email protected] > http://www.ch2m.com > > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Ron Greenman > Sent: Thursday, September 03, 2009 3:40 PM > To: [email protected] > Subject: Fire Flow > > When determining tank size on a property supplied only from a tank is the > sprinkler demand added to fire flow as a cumulative fire flow or is it > considered part of the fire flow? And if the former does the hose stream need > to be added or is it negated by the fact that the tank is already supplying > the hydrants? Example: 30,000 sqft fully sprinklered building requires a fire > flow (reduced 75% then rounded up to the minimum) of 1500 gpm for 2 hours > requiring a 180,000 gallon tank. The sprinkler demand is 650 gpm plus a 250 > gpm hose stream for one hour for a total of 54,000 gallons. Is the 54K > gallons included in whole or in part with the fire flow storage or is it > added? Thanks. > > -- > Ron Greenman > Instructor > Fire Protection Engineering > Bates Technical College > Tacoma, WA > > Member: > SFPE, ASCET, NFPA, AFSA, NFSA AFAA > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:[email protected] > (Put the word unsubscribe in the subject field) > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:[email protected] > (Put the word unsubscribe in the subject field) > -- Ron Greenman Instructor Fire Protection Engineering Bates Technical College Tacoma, WA Member: SFPE, ASCET, NFPA, AFSA, NFSA AFAA _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
