Stages and Hose Valves

[TravisMack]

Question on stages and hose valves.

Project in question has a proper stage that requires hose valves. In the past, I have just supplied them from the overhead system in the area (always coming off a 4" main). I have always included 50 gpm inside hose allowance for each valve combined with the overhead sprinkler calculations for the area. Additionally, I will calc them to provide 250 gpm each at 100 psi using the FDC as the water supply as if it were a true standpipe system.

I currently have a reviewer that is stating we have to add 250 gpm each interior hose allowance and add that to the sprinkler system. He is not asking for any specific pressure, just 250 gpm each, so we essentially have 500 gpm inside hose. When you combine this with the OH2 flows for the stage, you are looking at flowing just over 800 gallons through the system. The other option he gives is to supply them from an adjacent system. This will require running about 400' of 4" piping through the school. He states that if we supply them from an adjacent system, we do not need to add the hose allowance to the calcs.

I have sent the question to the AHJ, but I have not heard back yet. I think they are off on Fridays so I won't hear for a few days. What are your thoughts on how these hose valves are to be supplied and calculated?

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

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[cdafd]

Just passing info


905.2 Installation standard. Standpipe systems shall be installed in accordance with this section and NFPA 14. [F]


This section requires the installation of standpipe systems to comply with the applicable provisions of NFPA 14 in addition to Section 905. NFPA 14 contains the minimum requirements for the installation of standpipe and hose systems for buildings and structures. The standard addresses additional requirements not addressed in the code, such as pressure limitations, minimum flow rates, piping specifications, hose connection details, valves, fittings, hangers and the testing and inspection of standpipes. The periodic inspection, testing and maintenance of standpipe systems must comply with NFPA 25.

Section 905 and NFPA 14 recognize three classes of standpipe systems: Class I, II or III. The type of system required depends on building height, building area, type of occupancy and the extent of automatic sprinkler protection. Section 905 also recognizes five types of standpipe systems: automatic dry, automatic wet, manual dry, manual wet and semiautomatic dry. The use of each type of system is limited to the building conditions and locations identified in Section 905.3. The classes and types of standpipe systems are defined in Section 902.1.



905.3.4 Stages. Stages greater than 1,000 square feet in area (93 m2) shall be equipped with a Class III wet standpipe system with 11/2-inch and 21/2-inch (38 mm and 64 mm) hose connections on each side of the stage. [F]

Exception: Where the building or area is equipped throughout with an automatic sprinkler system, a 11/2-inch (38 mm) hose connection shall be installed in accordance with NFPA 13 or in accordance with NFPA 14 for Class II or III standpipes.


Because of the potentially large fuel load and three-dimensional aspect of the fire hazard associated with stages greater than 1,000 square feet (93 m2) in area, Class III standpipes are required on each side of these large stages. The standpipes must be equipped with a 11/2-inch (38 mm) hose connection and a 21/2-inch (64 mm) hose connection. The 11/2-inch (38 m2) connection is for the hose requirement in Section 905.3.4.1. The 21/2-inch (64 mm) connection is to provide greater flexibility for the fire department in its fire-fighting operations.

Stages, as used in this section, are those stages defined in Section 410.2, which include overhead hanging curtains, drops, scenery or stage effects other than lighting and sound. These were traditionally referred to as "legitimate stages." It is not an appropriate application of this section to require standpipes for elevated areas in banquet rooms, or theatrical platforms where the higher fuel loads associated with a legitimate stage do not exist.

The exception recognizes the benefit of the building or area being sprinklered. If so, then only a single 11/2-inch (38 mm) connection is required. This hose connection is intended to be used by the fire department and apply less water from the hose due to the suppression activity of the sprinkler system. Hose threads must be compatible with those of the fire department as required in Section 903.3.6.

In a fully sprinklered building it is acceptable to supply the hose connections through the same standpipe as the sprinklers. This is reflected in the reference to both NFPA 13, which acknowledges this concept, and NFPA 14, which contains similar provisions. If the provisions of NFPA 14 are used, although the standpipe must be wet and Class II in its installation, the design of the water supply and interconnection of systems can be in accordance with the requirements for Class II as well as for Class III standpipes.

 

[TravisMack]

Is this from the IBC commentary? This is exactly the information to describe what is needed. I doubt my AHJ will budge as this particular one has never budged on anything in the past that I am aware of. But, it is nice to know that I have even been overly conservative.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

"Follow" us at

https://www.facebook.com/pages/MFP-Design-LLC/92218417692

 

[stookeyfpe]

Just so I understand everything, is the stage sprinklered or the entire auditorium?

 

[cdafd]

2009 ibc

 

[TravisMack]

Everything is protected. Stage, auditorium and all other areas.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

"Follow" us at

https://www.facebook.com/pages/MFP-Design-LLC/92218417692

 

[sfallows]

then it looks like you should be able to install a hose valve per the nfpa 13, which requires it to be from an adjacent system

 

[stookeyfpe]

Travis:

Per 2012 IFC Section 905.3.4, exception a separate standpipe isn't required. Only one 1 1/2 inch hose valve is required. In my jurisdiction we waive this requirement because we don't allow Class II standpipes. Interestingly in the 2015 IFC Section 901.8.2 (which is new) allows the removal of existing occupant use hose valves under certain conditions. In my mind the hose valve is for overhaul purposes by FD use only.

The fact the 2015 IFC now allows the elimination of the hose makes one wonder why the technical committee just didn't man up and take out the Class II hose valves in fully sprinklered buildings. An argument could be made that based on the 2015 IFC Section 901.8.2 that the valve is for overhaul, fires involving stage fuel loads are commonly controlled with OH G1 or OH G2 densities so as a result, a single valve supplied from the sprinkler system doesn't require a separate standpipe system. This is further confirmed by the exception of IFC Section 905.3.4.

 

[MatthewJWillis]

Glad to see the code make some sense.
I am leaving off the two 1½" hose valves in a school I am doing now. I hope the AHJ understands that I do not want some high school hero trying to combat a fire that will develop faster than they can run...

R/
Matt

 

[sfallows]

Stookey

I still see some potential use of NFPA 13 hose valves in industrial settings which is probably why they haven't been so easy to kill off.

 

[stookeyfpe]

Sfallows:

I see no use for Class II standpipes unless one has an OSHA compliant structural fire brigade. I see them as nothing but valves to make money on because the code prescribes it, AHJs enforce it, designers spec it, fitters install and test it, and owners pay for its purchase cost and ITM. It's great for valve manufacturers.

When Class II standpipes were installed Russia was governed by a czar - that was 100 years ago after the Iroquois theater fire in Chicago. We've advanced so far in fire protection that we don't need them, IMHO.

 

[MatthewJWillis]

EVERY inspection I have done with a stage..., the hose still had the band on it.
Also the case for some major box retailers I inspected...


R/
Matt