1. Purpose. To establish a standard for the capacity flow testing of fire hydrants. While there are several methods available to test a hydrant, the following methods described are for single hydrant and two hydrant testing procedures. During plan reviews the Fire Marshal’s office will use both single hydrant and two hydrant methods for testing purposes.
2. Definition. Water is the most available tool used for the extinguishments of fires. The purpose of a Fire Department performing hydrant flow test is to determine whether the water system can furnish adequate amounts of water to meet the fire flow demands, based on the classification of the occupancies in the immediate area.
3. Equipment needed.
A. Hydrant wrench - two.
B. Hydrant cap pressure gauge - one.
C. Pitot flow gauge (blade or barrel type) - one.
D. Hydrant form (to record information).
4. Procedure (one hydrant test method, not be used for plan review flow requirements).
A. Select the hydrant to be tested.
B. Perform light maintenance.
C. Hydrant must be flushed prior to beginning flow test.
D. Choose which two and one-half-inch discharge will affect landscaping, traffic and the like the most and place a pressure cap gauge on this discharge. Open the hydrant fully. Note the pressure on the gauge. This is the static pressure. Record the static pressure on the hydrant report form. Close the hydrant slowly.
E. Take the two and one-half-inch-cap opposite the pressure cap gauge off the hydrant. Install a barrel type pitot gauge on this discharge opening if you have one.
F. Open the hydrant fully and note the pressure that is on the cap gauge. This is the residual pressure. Record the residual pressure on the hydrant report form.
G. Record the pressure reading on the barrel type pitot gauge. The pressure reading shown is the flow pressure. Record the flow pressure on the hydrant report form.
H. Close the hydrant slowly, remove all equipment and replace all caps.
I. Attempt to reposition any disturbed landscaping materials.
J. Proceed to the next hydrant.
5. Procedure (two hydrant test method, to be used for plan review flow requirements).
A. Select the hydrants to be tested.
B. Perform light maintenance.
C. Hydrants must be flushed prior to beginning flow test.
D. Choose which two and one-half-inch discharge will affect landscaping, traffic and the like the least for flushing the hydrant. Open the hydrant fully. Close the hydrant slowly after flushing the hydrant. Attach the pressure cap gauge to the two and one-half-inch discharge. Open the hydrant fully. Note the pressure on the gauge. This is the static pressure. Record the static pressure on the hydrant report form.
E. On the second hydrant choose which two and one-half-inch discharge will affect landscaping, traffic and the like the least for flushing the hydrant. Open the hydrant fully. Close the hydrant slowly after flushing the hydrant. Install a barrel type pitot gauge on this discharge opening if you have one or use a pitot tube. Open the hydrant fully.
F. With both hydrants open fully note the pressure that is on the pressure cap gauge. This is the residual pressure. Record the residual pressure on the hydrant report form.
G. Record the pressure reading on the barrel type pitot gauge. The pressure reading shown is the flow pressure. Record the flow pressure on the hydrant report form.
H. Close both hydrants slowly, remove all equipment and replace all caps.
I. Attempt to reposition any disturbed landscaping materials.
J. Proceed to the next hydrants.
(Ord. O-02-08, passed 6-5-2008)