Gregory Shvartsman, President of IGS Consulting in Fair Lawn, New Jersey, is working on a project in which the client wants supervisory air monitoring for manual dry standpipe systems, based on NFPA 14 (2019) Section 6.1.1, which states that “dry standpipes shall be monitored in accordance with NFPA 72 with supervisory air pressure.”
However, Gregory does not think this is feasible for manual standpipes since they do not have valves to hold air pressure, and a flapper in the siamese connection will not hold it either.
NFPA 14 just meant automatic dry standpipes, correct? Is supervisory air monitoring feasible for manual dry standpipes?
The Experts Weigh In
Our experts on ASPE Connect overwhelmingly agree with Gregory, for the following reasons.
The intent of NFPA is for supervisory monitoring to be provided when the air contained within an automatic dry standpipe is under pressure and is to be monitored for maintaining a proper minimum. Since manual dry standpipes do not contain any air that is under nothing other than atmospheric pressure, there is nothing to be monitored.
Also, such systems are not connected to any direct water source, and they are not “air tight.” Hence, any monitoring would be virtually impossible.
A Possible Alternative
A manual system cannot even be supervised with water. To have air supervision, the piping system needs to be airtight, as there are normally closed hose valves at all outlets. If the client wants air supervision, one expert recommends using a manual automatic dry standpipe system instead. The piping system is filled with domestic water through a backflow preventer. A flow switch complying with NFPA 72 should be provided on the downstream side of the backflow preventer to monitor any flow. This is preferable to an empty piping system because water will always be at the top outlet, and there is no wait time for the water to come all the way up from street level.
The Final Solution
While Gregory concludes that air supervision for manual standpipes is not practical, the client thinks otherwise. He decided to add a check valve after the siamese connection, plus a compressor and belts and other pieces required in New York for automatic standpipes under construction.
To alleviate concerns about where the air will go if firefighters connect the pumper before opening a hose valve, in New York applications there is a 2½-inch hose valve with a pressure gauge labeled “MANUAL AIR RELEASE, FIRE DEPT. USE ONLY” located near each siamese connection. The fire department releases the air while attaching hoses from the pumper and prior to energizing the standpipe system with water.
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