Grounding Equipment

DOE-HDBK-1092-2004

7.5.3

GROUNDING EQUIPMENT

ASTM Committee F-18, Electrical Protective Equipment for Workers, has developed and

published a consensus standard for protective grounds, ASTM Designation: F-855. This

voluntary consensus standard may be used by all Federal agencies for procurement purposes.

Therefore, grounding cables, clamps, and ferrules purchased should meet all the requirements

of ASTM Designation: F-855. Aluminum cables shall not be used for personal grounds.

The grounding of high-voltage lines and equipment will provide workers with additional

protection from electric shock if grounds are sized, selected, and installed properly.

7.5.3.1 AVAILABILITY

Grounding cables shall be available for use when work is being done on deenergized lines or

equipment.

7.5.3.2 APPROVED CAPACITY

Grounding cables shall accommodate the maximum fault current to which the cable or

equipment might be subjected.

7.5.3.3 GROUNDING CABLES AND HARDWARE

Personal protective grounding cables consist of appropriate lengths of suitable copper

grounding cable, with electrically and mechanically compatible ferrules and clamps at each end.

In addition, appropriate hot sticks are required for installing and removing the conductor-end

clamps to the conductors. Hot sticks are required for attaching ground-end clamps if the

grounded system and the worker are at different potentials. Cluster bars provide a low-

resistance means of connecting the ground-end clamps. Each of these components will be

discussed in the following subsections.

7.5.3.4 GROUNDING CABLES

Most of the grounding cables in use today (and available for purchase) are actually

manufactured for another purpose-principally as welding cable. These extra-flexible copper

cables with jackets are manufactured according to appropriate ASTM standards for both cables

and jackets, and can be expected to perform satisfactorily as grounding cables.

7.5.3.4.1

STRANDING

There are several classes of flexible cable with various stranding in the sizes normally used for

grounding cables.

7.5.3.4.2

JACKETS

Welding cables are nominally insulated at 600 volts. When used as grounding cable, the

insulation or jacket serves primarily for mechanical protection of the conductor. The flexible

elastomer or thermoplastic jackets are manufactured, applied, and tested according to ASTM

standards. Black, red, and yellow jackets are usually neoprene rubber compounds, while clear

jackets are ultraviolet-inhibited polyvinyl chloride (PVC). All jackets should have the AWG size

stamped or printed repeatedly along the length of the cable. The clear jacket allows easy visual

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