Minimum Flow Rates

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I am searching for a section or sections in NFPA 13 for the minimum Flow Rates
for a sprinkler system.

The Unified Facilities Criteria [ UFC ] requires a minimum rate of 1,000 GPM.

Can someone please provide some assistance, or maybe even the applicable
Code Sections in NFPA 13........I am using the 2013 Edition.

Thank you !

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[RLGA]

Does Table 11.2.2.1 provide the information you're seeking?

 

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Ron,

Much Thanks !

That certainly adds support & clarity to
what I was asked to find by my Supervisor.

$ - $ - $

 

[cda]

$ - $ - $

Ron,

Much Thanks !

That certainly adds support & clarity to
what I was asked to find by my Supervisor.

$ - $ - $

Do you mean for fire hydrant flow???


There are fire sprinkler systems that flow less than 1000 gpm

 

[cda]

Can you post the section out of UFC

 

[RLGA]

http://www.wbdg.org/FFC/DOD/UFC/ufc_3_600_01_2016_c2.pdf

See Section 9-2.1.

 

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cda,

No !.........I wanted to know the minimum Flow Rate for
an NFPA 13 designed sprinkler system......The building type
is for a typical Group B Occ. Group bldg. [ "very" low
hazard ]........Similar to what the UFC Standards require.

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[cda]

I read it to mean fire hydrant fire flow requirements.


This is not found in NFPA 13,
Plus look at 9-2.2 it throws you to NFPA 1 not 13.

9-2.1

Fire Flow for sprinklered Facilities must be a minimum of 1,000 gpm at 20 psi (3,785 L/min at 138 kPa). Where the Fire Flow cannot be met, the DFPE is permitted to approve a reduction in Fire Flow. Fire Flow is calculated independently of the Fire Water Demand.


Non-sprinklered Facilities. 9-2.2

Fire Flow must be in accordance with NFPA 1, except the following special Facilities.

 

[Insurance Engineer]

Go to section 11.2.3 to start with. For a Light Hazard occupancy you have a minimum of .10/1500=150 gpm for the sprinkler system, is this what you need? This is for a hydraulically designed system which 99% of systems installed today are, see figure 11.2.3.1.1. For hose stream allowances see table 11.2.3.1.2 , for light Hazard it is 100 gpm plus the 150 gpm from above gives you a total of 250 gpm minimum for sprinklers and hose.

 

[Insurance Engineer]

Does Table 11.2.2.1 provide the information you're seeking?

This table noted above is for pipe schedule systems which are not installed anymore ( say the last 20 years or so) since hydraulic systems require significantly less water hence cheaper to install.

 

[north star]

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Insurance Engineer,

Thanks for adding to my request for information.....That is quite
a difference in what is listed in the UFC vs. Section 11.2.3 in
NFPA 13.

QUESTION: Does the higher GPM requirement in the UFC take
precedent over Section 11.2.3 [ in the NFPA 13 ] ?

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[RLGA]

QUESTION: Does the higher GPM requirement in the UFC take
precedent over Section 11.2.3 [ in the NFPA 13 ] ?

I would say yes it does since the UFC is the owner's requirements. The owner can always demand that the code be exceeded as long as they're willing to pay the difference.

 

[north star]

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Thanks Ron !

The owner doesn't want to spend monies that are not
required.......In this case, the UFC appears to be "more
stringent", but, ...is the lower GPM amount provided by
**Insurance Engineer** adequate, or does the owner
go ahead and "require" the 1,000 GPM amount ?

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[Insurance Engineer]

Most insurance...like 99.9% ONLY require what NFPA 13 requires for sprinkler and hose demands. Given they are the ones that pay the losses and invented and mandated sprinkler systems in buildings in the first place I would think that would be OK. Even Factory Mutual only requires a sprinkler and hose demand.

Make sure you check NFPA 13 occupancy listings starting in section A 5.2 -A5.4.2 to get the correct density, or let us know and we can tell you what the density should be.

 

[cda]

If you are looking are this section of UFC

How do you get fire sprinkler requirements out of it and how do you get to NFPA 13 from it ????


9-2.1

Fire Flow for sprinklered Facilities must be a minimum of 1,000 gpm at 20 psi (3,785 L/min at 138 kPa). Where the Fire Flow cannot be met, the DFPE is permitted to approve a reduction in Fire Flow. Fire Flow is calculated independently of the Fire Water Demand.


Non-sprinklered Facilities. 9-2.2

Fire Flow must be in accordance with NFPA 1, except the following special Facilities.

 

[cda]

2-1.13 Fire Flow.
The flow rate of a water supply, measured at 20 psi (138 kPa) residual pressure that is
available for firefighting. [NFPA 1]

 

[RLGA]

This table noted above is for pipe schedule systems which are not installed anymore ( say the last 20 years or so) since hydraulic systems require significantly less water hence cheaper to install.

Other than its weapons, the DoD is not known to be current in many aspects.

 

[cda]

So what is the correct answer to this question???????




If you are looking are this section of UFC

How do you get fire sprinkler requirements out of it and how do you get to NFPA 13 from it ????


9-2.1

Fire Flow for sprinklered Facilities must be a minimum of 1,000 gpm at 20 psi (3,785 L/min at 138 kPa). Where the Fire Flow cannot be met, the DFPE is permitted to approve a reduction in Fire Flow. Fire Flow is calculated independently of the Fire Water Demand.


Non-sprinklered Facilities. 9-2.2

Fire Flow must be in accordance with NFPA 1, except the following special Facilities.

 

[Insurance Engineer]

So what is the correct answer to this question???????

Depends ......from an insurance AHJ we follow NFPA for new and existing buildings ie do they get a reduced insurance rate for a sprinkler system where the system is adequate for the occupancy and or do we even want to insure the company?? We do not follow building codes given we service the entire USA with some areas have great code enforcement and many having none or marginal enforcement. Hence why insurance companies have loss control staff and or hire 3rd party companies to evaluate the building COPE ie Construction, Occupancy, Protection and Exposure for each building we visit.

 

[Paul Sweet]

I think that fire flow says how much water needs to be available at a fire hydrant, while NFPA 13 says how much water has to be available at the building.

 

[khsmith55]

I concur with Paul, it looks like your mixing apples and oranges. Another thing to confirm is that IFC Appendix B has been adopted.

 

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O.K., ...MUCH THANKS for all of the responses.

Let me see if I can add some clarity.

This topic has to do with an existing military facility.
Plans have been submitted for review........The
owner [ i.e. - a State owned property ] wants to
upgrade this facility by adding a fire sprinkler system.

I was asked "How much fire flow is required ?"

I assumed that the fire flow was "what size of fire
water supply line is needed to bring in to the
property for any required hydrants and the sprinkler
system inside the facility".

Now, ...what say ye learned folks ?

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[cda]

Ok

My non engineer answer is

Depends

Seems like look at the building first

Occupancy type and use

Design the sprinkler system to that.

Have hydraulic calculations done to figure out fire sprinkler system demand.

Size the underground off of that.

But if they want more fire hydrant flow rate, on top of that, the main size outside might change.


The question has to many unknown variables.