OBTAINING CURRENT READING
Since the registers are never reset while the meters
are in service, the amounts recorded for any period of
time must be determined by subtraction. To obtain a
current reading, subtract the last recorded reading
from the current. dial reading. Remember, the
maximum amount that can be indicated on the usual
line meter before it turns to zeros and begins all over
again is 99,999 cubic feet, or 999,999 gallons. Thus,
to obtain a current measurement when the reading is
lower than the last previous one, add 100,000 to the
present reading on a cubic foot meter, or 1,000,000 to
the present reading on a gallon meter. The small
denomination scale, giving fractions of one cubic foot
or ten gallons, is disregarded in the regular reading. It
is used for testing only.
Q7. What is the purpose of a water meter?
Q8. What should you determine about flow in a water
meter before reading it?
Q9. For a circular meter, you should read the meter
in what direction?
LEARNING OBJECTIVE: Recognize types of
fire hydrants and methods for inspection,
flushing, and testing.
The fire department (or safety office) is
responsible for the selection and use of fire-fighting
equipment, including fire hydrants. It is the
responsibility of a Utilitiesman to ensure that water is
available to the hydrant and that control valves operate
Most fire hydrants consist of a cast-iron barrel
with a bell or flange fitting at the bottom to connect it
to a branch from the main; a valve, of the gate or
compression type, has a long stem terminating in a nut
above the barrel and one or more outlets. There are
many designs of fire hydrants, two of which are the
DRY-BARREL HYDRANT and the WET-BARREL
In cold climates, where freezing occurs, dry-barrel
hydrants are used (fig. 4-19). With this type of hydrant,
the drain valve or weep hole must be kept open in
systems where the groundwater level is below the
hydrant foot, so the barrel can drain and not freeze in
cold weather. A box placed over a hydrant affords
some protection against freezing and leaves the top of
the hydrant free of snow and ice. The hydrant is
equipped with two 2 1/2-inch hose outlets and a 4
l/2-inch pumper outlet whose threads conform exactly
to the standards specified in Screw Threads and
Gaskets for Fire Hose Connections, NFPA, 1963.
Where freezing temperatures do not occur, use
wet-barrel (or California) hydrants (fig. 4-20). With
this type of hydrant, all the packing glands must be
kept in good condition to prevent leakage as well as to
allow free operation of the stem controlling each
outlet. Valve seats for wet-barrel hydrants afford easy
access for inspection.
Hydrants exposed to traffic hazards must be
protected by appropriate guards. Most damage is
caused by an accident or by improper or careless
Much of this can be prevented when operating
personnel are made to realize that a properly
functioning fire hydrant is critical to the protection of
life and property at the activity. Without much extra
labor or effort, operating personnel can take several
precautions to keep the hydrant structure in good
condition. General precautions are listed below.
1. The operation of fire hydrants should be
restricted to personnel trained in this and allied work,
such as fire fighters, utility maintenance, and operating
2. For opening and closing the hydrant, use ONLY
an approved hydrant wrench. The reason is that ordinary
wrenches can ruin the operating nut.
3. Keep the hydrant drained when it is not in use.
This is particularly important in cold climates where ice
in the hydrant may make it inoperative.
4. Pipes should be connected only to draw off
water for fire-fighting purposes except in an emergency.
Any such connection must be removed immediately
after an emergency. Connections made to provide a
temporary supply for vehicle washing, irrigation, and so
on, is not permitted.
5. The hydrant valve should be kept in either the
wide OPEN or fully CLOSED position and never used
to throttle the flow of water. When it is necessary to
restrict the flow, separate globe valves should be
attached to the hydrant discharge outlet.