Application - hdbk10920146

DOE-HDBK-1092-98

reenergized, voltages induced from other energized lines, an energized line falls on the line being

worked, or there is a lightning strike near the line being worked.

The personal protective grounds should provide a low-impedance path to ground to ensure prompt

operation of the circuit protective devices. For more information, see Section 4.15.2 and IEEE 80.

7.5.2 APPLICATION

Certain methods and steps should be exercised when placing grounds and loads to protect workers

from high-voltage hazards.

7.5.2.1 DEENERGIZED LINES

When an energized line or equipment in excess of 600 V is removed from service to be worked on,

it shall be treated as energized until it is deenergized, tagged, locked if necessary, tested, and

grounded.

7.5.2.2 NEW CONSTRUCTION OR DISMANTLING OF FACILITIES

If isolating devices are not in place and energization is impossible from any source, single-phase

grounding is appropriate, acceptable, and safe. If energization is possible by the closure of a jumper

or isolating device, shorts and grounds shall be used unless conductor handling activity makes this

impractical or impossible because of line design or construction process.

7.5.2.3 MINIMUM APPROACH DISTANCE FROM UNGROUNDED CONDUCTORS

The minimum approach distances in Section 2.13.4.1 shall be maintained from ungrounded

conductors at the work location. (See Table 7-2 for 29 CFR 1910.269 Table R6). The ground may

be omitted if the making of the ground is impractical or the resulting conditions are more hazardous

than working on the lines or equipment without grounding. However, all work shall be done as if the

line or equipment were energized.

7.5.2.4 VISIBLE THREE-PHASE SHORT AND GROUND REQUIRED

Visible three-phase short circuiting may be accomplished through conductive parts such as guy wires

and unpainted metal tower members, but shall not be effected through a grounding mat or other

concealed conductors.

7.5.2.5 GROUND CIRCUIT

No power disconnect switch, power circuit breaker, transformer, wave trap, or fuse shall be part of

the protective grounding circuit.

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