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Construction Electrician Basic - Electricity handbook for electricians | Next
Figure 1-17.—Minimum safe distance for working around energized conductors. |
When the signalman desires to give the operator
any instructions other than those provided by the
established signal system, the operator should be
instructed to stop all motion FIRST.
Hand signals can be used effectively when the
distance between the operator and the signalman is not
great, but two-way radios should be used when the
distance or atmospheric conditions prevent clear
visibility.
Adequate lighting and signalling
arrangements must be available during night work, and
the equipment must not be operated when either is
inadequate.
PROCEDURES AND PRECAUTIONS FOR
LIFTING OPERATIONS
The most important rigging precaution is to
determine the weight of all loads before attempting to
lift them, to make ample allowances for unknown
factors, and to determine the available capacity of the
equipment being used. In cases where the assessment of
load weight is difficult, safe load indicators or weighing
devices should be fitted. This chapter also includes a
section dealing with the estimation of load weights.
It is equally important to rig the load so that it is
stable. Unless the center of gravity of the load is below
the hook, the load will shift.
The safety of personnel involved in rigging and
hoisting operations largely depends upon care and
common sense. Remember these safe practices.
Know the safe working load of the equipment
and tackle being used. Never exceed this limit.
Determine the load weight before rigging it.
Examine all hardware, equipment, tackle, and
slings before using them and survey defective
components. Discarded equipment may be used by
someone not aware of the hazards or defects.
Never can-y out any rigging or hoisting operation
when the weather conditions are such that hazards to
personnel, property, or the public are created. You must
carefully examine the size and shape of the loads being
lifted to determine if a hazard exists during high wind
speeds. Avoid handling loads that have large wind-
catching surfaces that could cause loss of control of the
load during high or gusty winds. The wind can critically
affect the loading and load-landing operation and the
safety of the personnel involved (fig. 1-16).
Figure 1-16.—Wind effects on load.
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