Program Policy Manual - VOLUME V - Mine Safety and Health ...

MSHA PROGRAM POLICY MANUAL VOLUME V
When permanent guarding is to be installed on a trolley or
trolley feeder wire by wrapping guarding material around the
conductor or when it is necessary to remove the trolley or
trolley feeder wire from the hangers or clips for installation of
the guarding material, the circuit shall be deenergized before
such work is performed.
75.510 Energized Trolley Wires; Repair
This Section contains exceptions to Section 75.509 and Section
75.511. These exceptions permit a miner who is properly trained
(see Section 75.510-1) and who wears approved and tested
insulated shoes and wireman's gloves to repair energized trolley
wires, even though the miner is not a qualified electrician
within the meaning of Section 75.153.
For the purpose of this Section, the term "trolley wires" would
also include trolley feeder wires and cutout switches used in
trolley circuits. For the purpose of this Section, the word
"repair" includes work such as straightening kinks in trolley
wires and replacing trolley wires and trolley feeder wires in the
clips or hangers, but does not include work such as installing or
removing trolley wires, trolley feeder wires or trolley cutout
switches.
Wiremen's gloves used to satisfy the requirements of this Section
shall have a manufacturer's rating of at least 750 volts. Rubber
boots satisfy the requirements of this Section, provided they are
maintained free from cuts, holes and excessively worn places.
Leather footwear rated for electrical hazards should not be used
to satisfy the requirements of this Section because leather shoes
can become highly conductive in the normally damp or wet
environment of underground coal mines. Insulated footwear and
wireman's gloves shall be closely inspected for damage and
defects before each period of use. Damaged or defective gloves
and footwear shall be replaced before repairs are performed on
energized trolley wires.
75.510-1 Repair of Energized Trolley Wires; Training
The training required by this Section shall be provided in
accordance with the applicable provisions of Part 48.
75.511 Low-, Medium-, or High-Voltage Distribution Circuits
and Equipment; Repair
For the purpose of this Section, electrical work is considered to
be the work required to install or maintain electric equipment or
conductors. Listed below are examples of work that is required
February 2003 (Release V-33) 55