While there are slight variations in procedures involving multi-valve, single valve and single outlet hydrants, the general process is basically the same.

Wet barrel and multi-valve hydrants Attach a pressure gauge and diffuser to the hydrant. Turn on the valve to the gauge and record the reading. Attach a pressure gauge to an adjacent hydrant or nearby hosebibb. Turn on the second hydrant or hosebibb and record the reading. Notes: We are taking a pressure reading, not flowing the second hydrant. The static readings taken at the hydrant and secondary location should be the same, plus or minus about a half pound per foot of elevation difference. Completely open the outlet to which the diffuser is attached. Take and record a pitot reading by inserting the pitot gauge into the center of the column of water. The inlet for the gauge should be placed a distance from the opening equal to the diameter of the opening. Take and record the residual pressure on the hydrant cap gauge. Take and record the residual pressure at the secondary location. Close the hydrant slowly being careful not to cause a "water hammer" and spike the pressure on the cap gauge above the normal static pressure. Verify that all valves closed properly, are not seeping or leaking, and that the hydrant is ready for service. Testing is a good time to inspect caps, paint, color codes, street markings and and other aspects of the hydrant, recording items which need attention so that follow-up service can be scheduled.

Recording the static pressure at the hydrant Taking secondary readings from a nearby hosebibb (or adjacent hydrant) Taking the pitot reading

Key Points: Make sure ditches and drains are free from leaves and debris and will adequately carry off discharged water. Don't waste water but flow the hydrant long enough so that the residual pressure stabilizes before taking readings. Always watch the flow of the water and take mitigating steps if runoff starts to overflow drainages and heads toward private property.

Multi outlet dry barrel hydrants Attach a pressure gauge to one outlet and take a reading. Attach a pressure gauge to an adjacent hydrant or nearby hosebibb and take a reading. (Compare readings as described in the wet barrel section.) Close the hydrant being tested and attach the diffuser basket to the second outlet. Completely open the hydrant, take and record a pitot reading as described in the wet barrel section. Take and record the residual pressure on the hydrant cap gauge. Take and record the residual pressure at the secondary location. Close the hydrant slowly being careful not to cause a "water hammer" and spike the pressure above the normal static pressure on the gauge at the secondary location. Verify that all valves closed properly, are not seeping or leaking, and that the hydrant is ready for service.

Taking a static reading before the diffuser basket is attached Taking the pitot reading

Single outlet hydrants Attach a pressure gauge to one outlet and take a reading. Attach a pressure gauge to an adjacent hydrant or nearby hosebibb and take a reading. (Compare readings as described in the wet barrel section.) Remove the pressure gauge and attach the diffuser basket to outlet. Completely open the hydrant, take and record a pitot reading as described in the wet barrel section. Take and record the residual pressure at the secondary location. Close the hydrant slowly being careful not to cause a "water hammer" and spike the pressure above the normal static pressure on the gauge at the secondary location. Verify that all valves closed properly, are not seeping or leaking, and that the hydrant is ready for service. Note: A few dry barrel bodies come with ¼" plugs in the body to which a test gauge can be attached. If a single outlet hydrant has a test outlet, a gauge can be connected to this outlet and the procedure for multi-outlet dry barrel hydrants used.

Taking a static reading Taking the pitot reading from the same outlet