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ATTACHING AND REMOVING GROUNDS Employees attaching and removing grounds shall comply with the following: 1. Grounding equipment should be visually inspected and all mechanical connections checked for tightness before each use. 2. The surface to which the ground is to be attached should be clean before the grounding clamp is installed or a self-cleaning clamp shall be used. 3. No ground shall be removed until all personnel are clear of the temporary grounded lines or equipment. When the grounding set is removed, it shall be disconnected from the line or equipment end first with an approved hot-line tool and moved to a point clear of energized conductors before the ground end is disconnected. [Refer to Section 4.15 and 29 CFR 1910.269(n)(6) and (7)]. 7.5.6 GROUNDING METHODS AND LOCATION OF GROUNDS IN ORDER OF PREFERENCE Employees installing grounds shall install them using the information given in the following sections. 7.5.6.1 WORK LOCATION Grounds should be installed at the work location with all grounded parts of different potential bonded together (on wood poles, all down guys, overhead ground wire, neutral conductor, and pole ground). The cluster bar assembly should be installed below the working area and jumper to the ground point or the neutral conductor and the phase conductor, a method of grounding termed "equipotential" grounding. It provides the greatest margin of safety for the lineworker by placing everything at equal potential, eliminating the possibility of the lineworker getting in series to ground. [See 29 CFR 1910.269(n)(3)]. 7.5.6.2 MULTIPLE WORK LOCATIONS AND SINGLE-PHASE GROUNDING AT WORK LOCATION If work is to be performed at more than one place in a line section, the line section shall be grounded at one location and the conductor be grounded at each work location to reduce the potential voltage difference across the work site. 7.5.6.3 OTHER LOCATIONS Grounds shall be placed at the work location or at each side of the work location and as close as practical to it. 7.5.7 TESTING WITHOUT GROUNDS Grounds may be temporarily removed when necessary for testing. Each employee shall use insulating equipment and be isolated from any hazard involved. Additional measures may be necessary to protect each exposed employee in case previously grounded lines or equipment become energized [See 29 CFR 1910.269(n)(9)]. 7.5.8 GROUND PERSONNEL In cases where ground rods or pole grounds are used for personal protective grounding, personnel working on the ground shall either maintain a safe distance from such equipment or use the appropriate equipment designed to prevent touch-and-step potential hazards. The term "touch potential hazard" refers to the difference in voltage measured between the grounding equipment and a worker in contact with the grounding equipment at the time it is accidentally energized. The term "step potential hazard" refers to the difference in voltage measured between each foot of the worker standing or walking in an electrical field created by high voltage brought to earth (See 29 CFR 1910.269, Appendix C and IEEE 80 for further information).
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