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Forward Flow Testing of Backflow Prevention Devices??

Forward Flow Testing of Backflow Prevention Devices??

Forward Flow Testing of Backflow Prevention Devices??

(OP)
Here is a link to an interesting article on the forward flow testing of a backflow preventor.

http://www.sprinklernet.org/sprinkleragesite/feature2.htm

How many plan reviewers remember to check for a test header or some other way to test the forward flow of the backflow prevention device annually? Once you start to get flows above Ordinary Hazard Group II occupancies, it is difficult to flow enough water thought the main drain valve to check the flow. The purpose of the annual test is to make sure the device is not stuck in the closed or partial position. The quarterly inspection by plumbers do to make sure the valves are closing is not the same test as required by NFPA 25.

The NFPA 25 test involves placing calibrated gauges on the device and flowing enough water to meet the highest sprinkler demand. The inspector then compares the pressure loss between the two gauges to the manufactures specification for the device. If the manufacture indicates a loss of 4 psi while flowing 1000 gpm and the results indicate 8 psi, this is a problem.

From an inspection point of view how many inspectors require compliance with foreword flow testing of backflow preventor as required by NFPA 25?

By the way the American Fire Sprinkler Association has a great FREE magazine with fire protection articles. It is free just by filling out and faxing in this form.


http://www.firesprinkler.org/downloads/AFSA-3010.pdf

RE: Forward Flow Testing of Backflow Prevention Devices??

How many designers know about the section and if they do include a means to get the required flow.

I still have a problem with some fire sprinkler companies and how the read NFPA 25 and what is required on an annual inspection.

RE: Forward Flow Testing of Backflow Prevention Devices??

(OP)
CDAFD,

What the New Jersey Division of Fire Safety did was to adopt all the forms in NFPA 25 annex B as part of the fire prevention code. So at least they have the form that has the items they need to check. They may not check it all, but at least it is easy to look for blanks or N/A on the form.

As far as making sure have a way to flow water to check the back flow, that is all part of the plan review process and why they get permits and we review plans.

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