When ascending steep, rocky slopes, do not
climb directly behind another crew member. If the
crew member were to accidentally fall, loosen a
rock, or drop something, it could mean serious
injury to anyone directly below the crew member.
EXCAVATIONS
WARNING
When your work involves excavation,
you should observe definite precautions to
prevent accidents.
To avoid slides or cave-ins, support the sides
of the excavations 5 ft or more deep by substantial
bracing, shoring, or sheet piling if the sides are
steeper than the angle of repose. The ANGLE OF
REPOSE is the maximum angle at which material
will repose without sliding. Trenches in partly
saturated or otherwise highly unstable soil should
be stabilized with vertical sheet piling or suitable
braces. Foundations of structures adjacent to
excavations should be shored, braced, or under-
pinned as long as the excavation remains open.
Excavated or other material should not be allowed
to accumulate closer than 2 ft from the edge of
an excavation. In a traffic area use barricades,
safety signs, danger signals, red lights, or red
flagging on at least two sides.
Do not enter a manhole until you are certain
that it is free from dangerous gases. Do not guess.
If there is any question at all as to whether a
sewer is free of gas, wait for clearance from a
competent authority. If necessary, provide first
for thorough ventilation. Do not smoke in
manholes; and if illumination is required, use only
a safety flashlight or lantern.
Avoid contact with ALL ELECTRIC wiring.
Never throw a metal tape across electric wires; if
you must chain across wiring, do it by breaking
chain. Avoid placing yourself so that you might
fall across wiring in the event of an accident.
When walking, stay at least 2 feet away from
the edge of a vertical excavation. Near
thoroughfares or walkways, excavations should
have temporary guardrails or barricades; and if
permissible, depending on combat conditions, red
lights or torches should be kept alongside from
sunset to sunrise.
TREE CLIMBING
Before climbing a tree, be sure it is safe to
climb, and carefully cheek the condition of the
branches on which you are likely to stand.
Different kinds of wood vary greatly in strength.
Oak, hickory, and elm trees that have strong,
flexible wood are safer for climbing than trees
such as poplar, catalpa, chestnut, or willow, which
have soft or brittle wood. Limbs of all trees
become brittle at low temperature—meaning that
they break more easily in cold weather than they
do in warm. Dead branches or those containing
many knots or fungus growths are usually weak.
When standing on a limb, have your feet as
close to the parent trunk as possible. Climb with
special care when limbs are wet or icy. Wear
goggles when working in bushy trees; they may
prevent an eye injury.
WARNING
Before climbing a tree, be sure there are
no overhead wires passing through its
foliage. If you MUST take a position in
a tree within reach of live wire, place some
sort of insulating safety equipment between
yourself and the wire. DO NOT allow tree
limbs to contact live wires because
moisture in a limb may cause a short
circuit.
If you require cutting tools to clear a
working space in a tree, haul them up with a
handline, and lower them by the same device.
Tools should never be thrown up into a tree or
down onto the ground.
UNDERGROUND AND
OVERHEAD LINES
If a structure has an access opening and is
below the street, such as a manhole or a
transformer vault, it should be protected by a
barrier or other suitable guard when the cover to
the access opening is removed.
CROSSING ICE
Do not cross ice unless, and until, you are
certain it will support your weight.
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