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fire sprinkler 200 lb acceptance test 1

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capnspa

Specifier/Regulator
Feb 20, 2003
3
As an AHJ we are required to witness the hydrostat testing of automatic sprinkler systems in commercial buildings.
We do not have the personnel to stay the 2 hours and sit around to make sure it stays at the 200 lbs.
We do check at the end time to see if it is at 200 lbs, seems a bit silly since we really dont know what goes on during those 2 hours. We are attesting and putting our name on the acceptance paperwork that the system is good.
If we had people who could hang around and do nothing for 2 hours they would probably cut our staff down.

What I would like to see happen is to have the fire protection contractor provide us with a letter attesting to his witness of the test of the system and the fact that it passed according to NFPA.
Has anybody heard of an AHJ doing it this way???
 
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We require a letter saying it was installed per 13

Also on 24 hr air test we bag the Gage and connection

You could do similar and have them remove the pump

Only had one company that tried to rig a test
 
If your jurisdiction can afford it, you can purchase a recorder and attach to the system. I would ensure you have some method of sealing the cover, such as with evidence tape that shows the cover seal was not tampered with.


Your jurisdiction will need to pay for calibration at least annually to ensure questions don't arise when gage accuracy is questioned.
 
The recorder is something new to me but a fantastic idea.
Affordable? Yes. Makes a lot of sense. We did think about the evidence tape idea today but the recorder is really good. Thanks for your replies folks
 
capsnspa,
As an AHJ, I have been "witnessing" 200 pound tests for nearly thirty years. I could never have stayed on site for the tests, as I was the only person doing inspections. When I wasn't able to return at the end of the two hours, I accepted the Contractor's Material & Test Certificate signed by the Project Manager/Job Superintendant and the Contractor.

During those times that I was able to be there before and after, I required the the pump removed from the test fitting and installing a plug after pressurizing the system. After returning and confirming the pressure, I had the contractor remove the plug and allow the pressure to excape as a means of confirming the accuracy of the guage. In this case, I signedthe certificate along with the contractor.

Hope the is helps.
 
Georgia requires certificate of competency holders to witness and sign the contractors material and test certificates. I am not lying or fudging for anyone. It is easy just to do it right.

Question for Stookey and others. What is the reasoning for removing the pump for two hours?

10.10.2.2 Hydrostatic Test.
10.10.2.2.1* All piping and attached appurtenances subjected to system working pressure shall be hydrostatically tested at 200 psi (13.8 bar) or 50 psi (3.5 bar) in excess of the system working pressure, whichever is greater, and shall maintain that pressure without loss for 2 hours.
10.10.2.2.2 Loss shall be determined by a drop in gauge pressure or visual leakage.

Why do we hydrostatically test in the first place? Certainly we don't expend all the energy to find a drip so much as to insure the system will stay together should the fire department connect to the fire department connection. Seems lots of people are losing sight of why we test other than the book says to.

As far as a small drip is concerned you can bet the owner will take care of getting that fixed.

Why disconnect the pump? We are looking for "a drop in gauge pressure or visual leakage" which indicates to me you can leave the pump attached, turn the pump on when should it drop below 200 psi and what's the difference if you have cycle the pump every 10 minutes?

In the appendix "To reduce the possibility of serious water damage in case of a break, pressure can be maintained by a small pump, the main controlling gate meanwhile being kept shut during the test."

"Pressure can be maintained by a small pump"?

Someone want to take a stab at telling me why my thinking is incorrect?
 
Chapter 10 deals with underground

And does allow a certain amount of leakage

It describes a testing method, have not seen underground tested in that manner
 
Didn't have my thinking cap on straight.

Still, 16.2.1.7 Loss shall be determined by a drop in gauge pressure or visual leakage.

Thinking of both CPVC and steel systems I've seen pressure climb considerably with a 10 degree rise in temperature over a few hour period. We've all see the reverse with a drop in temperature.

 
The purpose of the 200 pound test is to make sure the piping is tight and that it will withstand the pressure of a fire department pumper.
The reason for disconnecting the pump is to prevent anyone from pumping up a leaking system, thereby creating a false pressure test. Periodically pumping up a leaking system is contrary to the purpose of the test.
Many contractors that I have delt with, will pump up the system prior to my arrival to make sure the system is tight for the "Official Test" witnessed by me.
 
The purpose of the this test is to ensure the system is holding pressure on its own after being pump to 200 psi.
If i am an AHJ and I arrived to the job and the pump still attached to the connection I will failed test.
Once you pump system to 200 psi there is no need to continue have pump attached to system.
In Florida and other states you are required to have double valves and double gauges as a test connection so that AHJ can ensure test is not a fraud. I know that not every contractor is a fraud but you must treat all by same standards.

Properly threaded and grooved pipe should not leak at all. But you can also encounter pin holes and damaged gaskets thru the process.
Underground is also tested the same way.
 
If I'm not mistaken, the "A" form is required by 13 to be given to the AHJ so you have your documentation there. Regarding temperature changes; on warm days the contractors typically pump to 200 psi. on cold days they typically pump to 210 psi. in our region. Regarding hanging around; I typically use the time after checking pressure to walk the system layout to verify spacing, head styles and obstructions encountered after plan review and other trade battles with the fitters. The time spent while doing the witness can provide much more detail then just accepting documentation. I can't tell you how many times details were encountered over my 27 years of inspecting installations where things were discovered that were addressed saving time and $$ to the building owner. That's what reough-ins are for and we choose to do them while doing the hydrostatic because of staffing. It boils down to how one looks at system installations.

"Fire suppression is a failure in prevention"
 
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