TM 5-684/NAVFAC MO-200/AFJMAN 32-1082
way. Also, where the necessary trimming would re-
agronomist, entomologist, or pest control officer
sult in an unsightly or depleted tree, and the distri-
should be consulted before any chemicals are used.
bution lines cannot be raised or rerouted, the tree
Since misdirected or windblown spray can cause
should be removed.
irreparable damage to plant life adjacent to the
a. Felling. Where space permits, the tree should
right-of-way, do not spray when there is appreciable
be felled in one piece. It may then be cut up on the
wind. Protect personnel with rubber gloves and pro-
ground. To drop the tree in the exact spot desired
tective clothing when handling the chemicals.
requires experience and judgment on the part of the
Manufacturer's instructions should be followed in
foreman. First, cut a notch near the ground line
mixing and applying chemicals. Local contractors
about one-third through on the side toward which
are often available, who are experienced and
the tree is to fall. Then cut from the opposite side
equipped to do chemical clearing.
with a saw, a few inches (several millimeters) above
the previous notch. If there is any question as to the
4-61. Posionous plants.
direction the tree will fall, use hand lines or a pull-
Poisonous plants are frequently encountered when
ing line as insurance.
trimming trees and removing brush. If the poison-
b. Piece-by-piece. Where adjacent structures, wire
ous oily substance from these plants gets on the
lines, highways, or other limitations prevent felling
skin, it should be removed as soon as possible.
the tree, it may be taken down piece by piece. Start-
Smoke, insects, clothing, and direct contact can
ing on the lower limbs and working toward the
spread the toxic effects, which are more likely to
crown, limbs are removed, one by one, as in trim-
ming. If the trunk cannot be felled, it must also be
occur when the skin is covered with perspiration. A
removed in pieces.
preventive cleanser is available which cleanses and
c. Stumps. The usual practice is to cut the stump
decontaminates poisonous oils. Apply the cleanser
at the ground line. This can be done with a power
to the exposed area of the skin for the recommended
saw or hand crosscut saw by excavating at the sides
period and then rise off with cool running water.
of the stump to provide clearance for operation of
Other methods, which are not preventive treat-
the saw. Power equipment of various types is avail-
ments and do not alleviate the damage, are washing
able for removal of stumps or for cutting them to
the exposed areas of the skin with warm water and
slightly below the ground line.
brown laundry soap or with rubbing alcohol, then
rinsing with clear water, and drying the skin. No
4-60. Tree killing chemicals.
brush should be used, as this would irritate the
Various chemicals are now available that will kill
skin. Clothing exposed to the poison should also be
the plant or retard its growth. The installation
Section XV - LIVE-LINE MAINTENANCE
4-62. live-line maintenance requirements.
4-63. Categories of energized-line mainte-
With the use of various types of aerial equipment
and hot-line tools, many operations in the mainte-
Energized-line maintenance means work on any
nance of overhead distribution lines may be per-
line electrically connected to a source of potential
difference, or electrically charged so as to have a
formed while these lines are energized. Safety pre-
potential difference from ground. Synonyms are
cautions are of utmost importance and personnel
alive, current carrying, hot, and live. Voltage is con-
engaged in this type work must be thoroughly
sidered medium or high if it is over 600 volts up to
trained in the procedures and use of the tools and
230,000 volts, see section II. The categories of work
equipment. Departmental safety publications
apply to the potential difference from ground at
should be consulted for restrictions and certification
which the worker operates and specific precautions
requirements on live-line maintenance at various
apply to each potential.
voltage levels. Also see requirements in chapter 1,
a. Workers at ground potential. Workers are lo-
section II. Trained personnel should be familiar
cated on the structure supporting the conductor or
with ANSI/IEEE 516 and ANSI/IEEE 935, which
on other work platforms and remain essentially at
provide expanded guidance on energized power-line
ground potential using insulating tools and equip-
maintenance methods and live-line tool care. The
"Lineman's and Cableman's Handbook" provides
pictorial data on tools, equipment, and live-line op-
b. Workers at intermediate potential. Workers are
isolated from grounded objects by insulating means,