Leadership

Selection of Residual Hydrant Is Key to Making Flow Tests

Issue 7 and Volume 123.

Selection of Residual Hydrant Is Key to Making Flow Tests Fire flow tests are made on water distribution systems to determine the rate of flow available at various locations for fire fighting purposes. Depending upon the method to be employed in combating fires at a particular location, a certain residual pressure in the main is specified. At this residual pressure, the rate of flow must be available if the water is to be used effectively. As an example, if fire department pumpers are to be used to supply hose streams, a residual pressure of 20 psi is usually specified. This residual pressure in the mains is necessary to overcome the friction loss in the hydrant branch, in the hydrant, in the suction hose and fittings of the pumper, and to provide the water velocity needed at the pumper suction inlet. If hose streams are to be used directly from hydrants,…

Subscribe to unlock this content

Subscribe Now