Grounding - hdbk109220040095

DOE-HDBK-1092-2004

5. Communication conductors shall be installed in accordance with 30 CFR 57.12010 and

75.516-2.

6. Lights and lamps shall be properly guarded if they pose a hazard and shall be kept away

from combustible material.

5.10.2 GROUNDING

All electric circuits shall have a grounding system. The system shall protect people from injuries

or fatal shock on inadvertent contact. The system shall limit the voltage on all electrical

equipment with noncurrent-carrying metallic parts. Grounding of ac and do equipment shall be

in accordance with 29 CFR 1910.304(f).

Equipment grounding conductors shall comply with the standards expressed in 29 CFR

1910.304(f)(6)(i).

All installations, modifications, or repairs pertaining to grounding systems shall be followed by a

continuity test to ensure the integrity of the systems. The frequency and requirements of he

review shall conform to 30 CFR 57.12028.

5.10.3 POWER CABLES AND CONDUCTORS

Cables and insulated conductors shall be protected against physical damage, adverse

environmental conditions, and failure of adjacent mechanical equipment.

Cables and insulated conductors shall not be supported from or be in contact with pipelines.

Sufficient clearance between pipelines and cables is required to prevent shock hazards when

maintenance activities are being performed. A minimum clearance of 10 ft above floor level shall

be maintained for all overhead cables/conductors overhead not protected against physical

damage as set forth in NFPA 70E.

Electric conductors shall be of a size and current carrying capacity to ensure that a rise in

ambient temperature does not exceed the rating of the insulation and conductors. The

capacities of electric conductors supplying electrical equipment shall be in accordance with the

tables set forth in the NEC Article 310. In the case of medium- or high-voltage cable, the

manufacturer's ratings shall not be exceeded.

Splices, terminations, and repairs of electric conductors and power cables shall be permitted

and shall conform to the requirements expressed in NFPA 70E.

Surge arresters and lightning protection are required for underground facilities and shall

conform to the requirements found in 30 CFR 57.12069 and 75.521. Lightning arresters shall be

inspected for damage at least annually or after each electrical storm.

Power cables and insulated conductors in shafts and bore holes shall be supported. Support

structures and guy wires and supports for cables and conductors shall conform with the

requirements expressed in 30 CFR 57.12083.

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