Distance from FDC to the Nearest Hydrant?

5/20/2019

For years on my code calls I have asked the Authority Having Jurisdiction what the maximum distance the nearest hydrant is allowed to be away from a building's fire department connection. I get answers that range from 50 feet to 400 feet or even more.

I was looking into the code basis behind this question, and the only applicable section that I found is the International Fire Code, Section 507.5.1.1 that addresses hydrant locations for standpipe systems:

"Buildings equipped with a standpipe system installed in accordance with Section 905 shall have a fire hydrant within 100 feet (30 480 mm) of the fire department connections. Exception: the distance shall be permitted to exceed 100 feet (30 480 mm) where approved by the fire code official."

Is there any relevant requirement for hydrants near fire department connections for sprinkler-only systems?

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Dan Wilder

5/20/2019 10:16:24 am

NFPA 14 - 19' Edition states in 6.4.5.4 the the maximum distance is 100' between the FDC and the nearest fire hydrant unless allowed by the AHJ to be further.

This goes back through at least the 07' edition using the same section.

JEN

5/20/2019 10:32:21 am

Dan, I think the person who posted is looking for a distance from FDC to hydrant for a sprinkler system only (NFPA 14 I understand is only for standpipe FDC's).

I am curious about this one as well and don't have an answer. I have always just done 100 feet even if it is just the sprinkler system, but I have no basis for this other than applying the standpipe code reference to sprinkler system as well.

Clifford Schulze

5/20/2019 10:40:21 am

There is no reason to believe that the distance would be any different for a sprinkler system only vs a standpipe system. The distance is related to the amount of hose the fire department needs to run to make the connection.

Jimmy Landmesser, Jr.

5/20/2019 11:03:50 am

Good afternoon,

Similarly to IFC (2012) Section 507.5.1, NFPA 1 (2018), Sections 18.5.2 and 18.5.3 have requirements for maximum distance of hydrants to the closest point on the building. It is 400 ft. for all buildings except one and two-family dwellings where 600 ft. is allowed.

NFPA 13 (2019), Section 16.12.5.7 requires the FDC to be located at the nearest point of FD apparatus accessibility or as approved by the AHJ.

So, unless approved by the AHJ, the FDC should not be located any further than 400 ft. except one- and two- family dwellings (600 ft. allowed). The expectation for a sprinkler system is that it automatically actuates and continues to flow at the minimum design for a specified amount of time (30 mins for light, 60-90 for ordinary and 90-120 mins for extra hazard). The standpipe system requires manual intervention and so closer fire department access is essential to limit response times, friction loss through hose lays, etc. I know a lot of jurisdictions reduce the minimum distance from ANY FDC to a hydrant, sprinkler or standpipe.

Nimal Tissa Wijetunga

5/20/2019 11:06:45 am

Fire Hydrant shall be positioned minimum of 6 meters and the maximum of 30 meters the facility it is going to be protected.

The breaching inlet or fire department connection shall be positioned withing 18 meters from the fire vehicle hard standing position.

In this situation, where hose can be fixed to the fire vehicle from the hydrant point where water can be drawn and and from the other side of the vehicle, a hose can be fixed to the fire vehicle and then fixed to the Breaching inlet here the fire vehicle can pump water to the stand pipe /sprinkler system in the building to replenish the availability of the water.

MODERATOR

5/20/2019 11:09:22 am

Nimal, please provide references when you cite requirements. It benefits everyone to discuss based on codes and standards. Thank you!

5/20/2019 11:52:53 am

Pls refer Chapter 2 Section 6.3 and Chapter 2 Table 2.3 of UAE Fire and Life safety code of practise - 2011 edition. and NFPA 24 - Chapter 4 & 7 for information.

PETE

5/20/2019 12:34:37 pm

I would like to comment on something here that for those who are aware or are reviewing plans should be obvious, but it isn't obvious if you're inspecting a physical site or if you're just new to the industry. My comment is not meant to be patronizing.

If you have private service mains that are supplied by a pump and they feed a plurality of sprinkler systems as well as private hydrants, and the FDC is connected to the same private service main, it is not sufficient to have a hydrant from the same private service main within close proximity to the FDC. Drawing suction from the same water that the FDC discharges to will not allow for differential pressure to be created by the pumper. Regardless of whether the AHJ wants the hydrant to be 100 ft or 50 ft away, the hydrant that is designated the "FDC" hydrant, needs to be supplied from upstream of the fire pump suction and any backflow preventer. It's usually a city hydrant, but not always.

Jon Nisja

5/20/2019 02:13:28 pm

These comments are from an AHJ perspective. Without sounding too flippant, the answer to this and almost any code question is "it depends".

Our state has adopted the 2012 International Fire Code (IFC) and is in the process of updating to the 2018 IFC. This requirement was new to the 2012 IFC and was likely an attempt to correlate with NFPA 14 requirements for the same.

We have interpreted this to mean standpipe-only systems, not sprinkler system FDCs and not combination sprinkler/standpipe connections. For sprinkler or combination FDCs, we default to the maximum hydrant distance, which is 400 feet (IFC 507.5.1, as amended in our state).

Our rationale: history has shown us that sprinkler systems buy us time so the 100 ft. spacing from standpipe FDCs to hydrants is not necessary.

This is especially true with low and moderate hazard buildings. The vast majority of the 1,100 sprinkler system activations that we studied (76% of wet systems and 57% of dry systems) were extinguished with a single sprinkler. In 94% of the wet systems and 82% of the dry systems, the fire was extinguished with four or fewer sprinklers. Hence, the need to immediately connect to and charge the sprinkler FDC is greatly reduced.

That said, if this were a high hazard occupancy with high challenge fires where augmenting the water supply quickly was a concern, as an AHJ, I might ask for the hydrant to be located closer. Hence, the answer "it depends".

JAMES

5/20/2019 02:19:23 pm

Well said Jon! Not sure where your jurisdiction is, but that's a very thorough and well-thought answer to an answer that can feel arbitrary to designers. This is very helpful information to help foster quality discussions with AHJs in the future.

5/20/2019 03:15:40 pm

Thanks for your feedback, James. I am with the Minnesota State Fire Marshal Division. We are presently conducting research on our 1,100 + sprinkler saves in recent years (similar to the research studies that NFPA does on sprinkler saves). Hopefully that data will be published within a few months. Our preliminary data appears positive and we are happy to share our data with interested parties. jon.nisja@state.mn.us

p.s. We try to apply performance measures, experience, and common sense but not everyone likes that or has had the same experiences. People often forget that the beginning sections of all of the codes and standards talk about a reasonable level of fire protection, not an absolute "zero-risk" level of fire protection built on "what-if" scenarios

sean

5/20/2019 03:14:26 pm

I agree with most of what you said.

FDC to fire hydrant maximum spacing only applies to FDC serving a standpipe system.

I would apply the same restriction to a building with sprinklers and a standpipe system combination or otherwise. There is a subsection in NFPA 14 about combination systems and it does not provide relief for FDC spacing.

Chris Ferguson

5/21/2019 07:28:25 am

One thing I would like to add for those working in IFC locations, if the jurisdiction has adopted appendix C, the 400' and 600' distances can get altered. It will also give a more definitive amount of hydrants needed + spacing requirements. Sometimes it is a pain to apply however.

5/21/2019 10:07:34 am

The question asked is the distance from FDC or Breaching inlet to the nearest Yard Fire Hydrant.

Stand pipe system is in the building and usually 1 inch or 11/2 inch in size and refers to NFPA 14.

Yard Fire Hydrant is in the yard with 21/2" outlets ad refers to NFPA 24.

Distance from FDC to the Nearest Hydrant?

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