5,000 feet in long supply lines and 1,200 feet in main
distribution loops or feeders. All branch mains
connecting to feeder mains or feeder loops should have
valves installed as close to the feeders as practical, so
branch mains can be taken out of service without
interrupting the supply to other locations. In the areas
of greatest water demand or when the dependability of
the distribution system is particularly important,
maximum valve spacing of 500 feet may be
appropriate. At intersections of distribution mains, the
number of valves required is normally one less than the
number of radiating mains; the valve omitted from the
line is usually the one that principally supplies flow to
the intersection. Valves are not usually installed on
branches serving fire hydrants on military
installations. As far as practical, shutoff valves should
be installed in standardized locations (that is, the
northeast corner of an intersection or a certain distance
from the center line of a street), so they can easily be
found in emergencies.
For large shutoff valves
(approximately 30 inches in diameter and larger), it
may be necessary to surround the valve operator or
entire valve with a vault to allow for repair or
replacement. In important installations and for deep
pipe cover, pipe entrance access manholes should be
provided so valve internal parts can be serviced. When
valves, vaults, or access manholes are not provided, all
buried valves, regardless of size, should be installed
with special valve boxes over the operating nut to
permit operation from ground level by the insertion of
a special long wrench into the box.
Proper clearance should be maintained between
hydrants and poles, buildings, or other obstructions, so
the hose lines can be readily attached and extended.
Generally, hydrants are located at least 50 feet from a
building and in no case are they located closer than 25
feet to a building, except where building walls are
blank fire walls. Hydrants may be located adjacent to
blank portions of substantial masonry walls where the
chance of falling walls is remote.
Street intersections are the preferred location for
fire hydrants because fire hoses can then be laid along
any of the radiating streets. However, the likelihood of
vehicular damage to hydrants is greatest at
intersections, so the hydrants must be carefully located
to reduce the possibility of damage. Hydrants should
not be located less than 6 feet nor more than 7 feet from
the edge of a paved roadway surface. When hydrants
exceed this distance, consider stabilizing or surfacing a
portion of the wide shoulders adjacent to the hydrants
to permit connection of the hydrant and pumper with a
single 10-foot length of suction hose. In some
circumstances, it may not be practical to meet this
criteria. Then try not to exceed 16 feet (two sectons of
hose) to the pumper.
Hydrants should not be placed closer than 3 feet to
any obstruction nor in front of any entranceway. The
center of the lower outlet should not be less than 18
inches above the surrounding grade, and the operating
nut should not be more than 4 feet above the
In aircraft fueling, mass parking, servicing, and
maintenance areas, the tops of hydrants must not be higher
than 24 inches above the ground with the center of the
lowest outlet not less than 18 inches above the ground.
The pump nozzle should face the nearest roadway.
Here are rules for plumbing safety.
Keep the job clean.
Pick up scrap pieces of pipe.
Keep all tools and materials off the job when not
Keep the shop floors dry and clean.
Keep the stockpiled materials carefully braced
and blocked to prevent falling.
Lift with your legs, not your back.
Use pipe tongs for carrying heavy pipe sections.
Use proper tools for the job at hand.
Keep tools in good condition.
Use care in handling torches and hot lead.
Do not pour hot lead into a wet joint.
Use safety goggles, when required.
After installing fixtures, test the pipes for 1eaks
and proper drainage before leaving the job
Hydrants should be located what distance from
The top of a hydrant must not be higher than how
many inches above the ground?