NFPA 14 Standpipe Most Remote Calc

[sfallows]

This is a question about which hose connections are required to flow on the most remote standpipe. One party is arguing that you calc the top two as defined by the top hose valve + the testing hose valve while the other party defines it as the top two excluding the testing valve (as in the top two floors in this case)

On a Class I system per NFPA 14 2007 it requires "the minimum flow rate for the hydraulically most remote standpipe shall be 500 gpm, and the calculations proeedure sall be in accordance with 7.10.1.2" (7.10.1.1.1)

7.10.1.2 says in 7.10.1.2.1 "hydraulic calcs and pipe sizes for each standpipe shall be based on providing 250 gpm at the two hydraulically most remote hose connections on the standpipe and at the topmost outlet of each of the other standpipes at the minimum residual pressure required by section 7.8"

lastly 7.3.2.2 "An additional 2-1/2" hose connection shall be provided at the hydraulically most remote portion of the system to facilitate testing"

Anyone see anything that dictates which method is correct. While I understand that flowing the testing valve and the one next to it will be the most demanding, the placement (location) of said testing valve is determined by calculated hydraulic demand.

 

[cdafd]

7.10.1 Class I and Class III Systems.

7.10.1.1* Flow Rate.

7.10.1.1.1 For Class I and Class III systems, the minimum flow rate for the hydraulically most remote standpipe shall be 500 gpm (1893 L/min), through the two most remote 2 1/2 in. (65 mm) outlets, and the calculation procedure shall be in accordance with 7.10.1.2.

 

[cdafd]

3.3.3.2 Hose Connection. A combination of equipment provided for connection of a hose to the standpipe system that includes a hose valve with a threaded outlet.

 

[sfallows]

You referenced 7.10.1.1.1 of the 2010/13 edition. The AHJ has adopted 2007 which reads slightly differently (the text is in my first post). The problem is 7.3.2.2 which allows for one party to argue it's there for testing.

 

[cdafd]

OK, My take on this section is that normally you have one outlet in the stairwell, and to get the 500 GPM flow for the test they want two, or 250 gpm each.


Chapter 7 Design


7.3 Locations of Hose Connections.

7.3.1* General.

7.3.1.1 Hose connections and hose stations shall be unobstructed and shall be located not less than 3 ft (0.9 m) or more than 5 ft (1.5 m) above the floor.



7.3.1.2 The hose connection shall not be obstructed by the closed or open door or other objects on the landing.




7.3.2* Class I Systems. Class I systems shall be provided with 2 1/2 in. (65 mm) hose connections in the following locations:


(1)
At the highest intermediate landing between floor levels in every required exit stairway


(2)
On each side of the wall adjacent to the exit openings of horizontal exits


(3)
In other than covered mall buildings, in each exit passageway at the entrance from the building areas into the passageway


(4)
In covered mall buildings, at the entrance to each exit passageway or exit corridor, and at the interior side of public entrances from the exterior to the mall


(5)*
At the highest landing of stairways with stairway access to a roof, and on roofs with a slope of less than 3 in 12 where stairways do not access the roof




7.3.2.1 Hose connections shall be permitted to be located at the main floor landings in exit stairways where approved by the authority having jurisdiction.



7.3.2.2 An additional 2 1/2 in. (65 mm) hose connection shall be provided at the hydraulically most remote portion of the system to facilitate testing.

 

[GeorgeMech]

The calculation shall be done for the most remote hose connections which includes the 2 1/2 test connection and the adjacent hose connection since this will be the basis of selecting the pump capacity if standpipe is the most demanding in your system.