Trying to override inspector¦s test conection 1

[DavidCR]

We have a small automatic sprinkler wet system consisting of 4 sprinklers that protects only one room.

The most remote sprinkler is not far from the feeder riser (5 meters) and we don´t have a suitable draining point near it, the draining point would be reached routing a pipe back near the riser.

My question is if one can override the requeriment of an inspector´s test conection at the farthest point of the system, and if the main drain can be used as an inspector´s test conection as a substitution for the other.

In our design the system can be drained completely using the main drain at the alarm check valve on the riser.

I read the NFPA 13 (1996), where it deals with the inspectors test conection, but I´m not sure what is the correct intepretation of the code on this.

 

[stookeyfpe]

I do not have the 1996 edition of NFPA 13. I am referencing the 2002 edition and assume you have a wet pipe system. The current requirements of NFPA 13 require an inspector test connection. The inspector test connection can be connected to a main drain but a main drain cannot substitute for an inspector's test connection because the test connection orifice must deliver a flow equivalent to the sprinkler with the smallest orifice installed in the system.

A number of manufacturers produce a device that meets the inspector test connection requirement of NFPA 13 and can be installed in the main drain. See the following link from one source:

http://www.tyco-fire.com/TD_TFP/TFP/TD455.pdf

 

[PEDARRIN2]

There are devices which serve both functions. They are typically located at the riser.

 

[TravisMack]

The AGF Test-n-Drain would work in this situation. It serves as the main drain and test connection. Just make sure it is located ABOVE the flow switch on the riser.

 

[PEDARRIN2]

Why does it need to be above the flow switch on the riser?

I have seen some installation where the floor's 2.5" sprinkler main comes off the 4" standpipe in a stairwell. The supervised valve and flow switch are located on the horizontal pipe off the standpipe. Then the pipe has a tee oriented downward then an elbow back to the horizontal toward the standpipe. The AGF (or similar apparatus) is located on this smaller (~1.25 to 2")horizontal pipe. This pipe connects to the sprinkler drain riser.

Why would that be incorrect since the AGF is below the flow switch?

 

[TravisMack]

Ok..let me clarify. You want it downstream of the flow switch. If you don't, you won't trip the flow switch for the test. If you have a single riser, like mentioned above, then the test-n-drain is above the flow switch.

On a multi-story building, where you have individual floor control valve assemblies like you described, you simply need to have the test-n-drain on the system side of the flow switch.

I have seen several installations over the years where the test-n-drain device was installed below (on the supply side of) the flow switch and no one could figure out why the alarms would not go off when the test connection was opened. A simple plug, new mech tee and repipe the drain on the system side of the flow switch...voila..the problem resolved.

 

[DavidCR]

I got the idea, thanks a lot to everybody.

 

[cdafd]

So you have a spinkler with only FOUR heads and that is all???

IF so than a flow switch is not required unless you have a local requirement for it to be and since the flow switch is not required an inspector test connection is not required.

 

[DavidCR]

Cdafd
Could you please tell where can I find this rule you are refering to?

 

[TravisMack]

CDAFD,

Are you referring to the usual requirement of not having a central station monitoring required for projects of less than 100 sprinklers as found in most building codes.

It is my understanding that all systems must have some means of alarm. You may be able to get away with an alarm check valve and water motor gong, so you don't need a flow switch. But, I thought you always had to have an alarm device.

 

[cdafd]

in the 2002 nfpa 13 section
8.6.1.1 local waterflow alarms shall be provided on all sprinkler systems haveing more than 20 sprinklers.

5-15.1.1 in the 1999

and maybe 4-15.1.1.2 in the 1996

 

[TravisMack]

ok...now, I have been shown the light!!! Thank you for that section.

 

[stookeyfpe]

CDA:

I disagree as to having a sprinkler system composed of 4 sprinklers and not requiring a test connection. Section 8.16.4.2 of NFPA 13 (2002 ed.) is very specific and does not specify a minimum number of sprinklers. When a sprinkler system is required, an inspector's test connection is required.

 

[cdafd]

stookeyfpe

How aboout 8.16.4.2.1 last sentence "shall be provided to test each waterflow alarm device for each system."

So if you go back to 8.6.1.1 where it says a waterflow alarm is required for 20 and over and you have a system with under 20 and no waterflow alarm is required.

It seems 8.16.4.2.1 would not be in play since a waterflow alarm is not required and since not required and not installed there is nothing to test???

 

[FireRanger]

Good questions from all. My 2 cents... The inspectors test connection also verifies that water is available at the last head on the system, and that feed mains and branches are not clogged. Without a inspection test, one could not verify that the system is indeed clogged. A 2" main drain test only verifies base of riser and underground stoppage.

 

[cdafd]

FireRanger

Sorry on a wet system the inspector test can be at the riser, code does not specifiy where it has to be, on a multi story the inspector test can be at the tap for the floor, on a dry system it would not tell you if every line is clear.

So inspector test is there for what is is designed testing the flow switch, yes it can tell you a few other things at times.

 

[FireRanger]

cdafd

NFPA13 verbatim:

This test connection should be in the upper story, and the connection preferably should be piped from the end of the most remote branch line. The discharge should be at a point where it can be readily observed. In locations where it is not practical to terminate the test connection outside the building, the test connection is permitted to terminate into a drain capable of accepting full flow under system pressure.

Gotme, its a "should" & not a "shall". However all the approving eng. I know would never accept a test connection at the riser. It is interesting to note that on high riser floor sections, the test connection is indeed there for the purpose of the flow switch activation.

 

[TravisMack]

FireRanger:

You are quoting stuff from the appendix. Unless the AHJ has adopted the appendix as part of the requirements, it is typically not enforceable.

The ITC at the end of the system is only required for dry systems. That is because you are trying to prove you can get water to the end of the system in 60 seconds. And, the 60 seconds is only required on systems larger than 750 gallons.

For a wet system, the ITC only serves the purpose to ring the alarm. It does not tell you if there is a blockage - except in a single path - to the ITC. Therefore, there is no reason to have it at the end of the system.

I once had an AHJ state that you wouldn't know if there was a blockage at all of the welded outlets on the main in a grid if the ITC was at the riser. I informed him that I could block every outlet on the main EXCEPT the line that goes to the ITC and you would not know until you flowed water from each line. After that, he no longer required the ITC to be located at the end of the system.