501 EM 385-1-1 Construction Safety Hazard Awareness for Contractors Sections 7 - 13

Material Handling and Storage

Stringing and clipping operations must be discontinued during an electrical storm in the vicinity.

11.I.40 Reliable communications between the reel tender and pulling rig operator must be provided.

11.I.41 Each pull must be snubbed or dead ended at both ends before subsequent pulls.

11.I.42 Before stringing parallel to an existing energized transmission line, a determination, by a QP, must be made to ascertain whether dangerous induced voltage buildups will occur, particularly during switching and ground fault conditions. When there is a possibility that such dangerous induced voltage may exist, the employer must comply with the provisions of Sections 11.I.42 through 11.I.49 in addition to the provisions of Sections 11.I.25 through 11.I.40 unless the line is worked as energized.

11.I.43 When stringing adjacent to energized lines, the tension stringing method or other methods that preclude unintentional contact between the lines being pulled and any person must be used.

11.I.44 All pulling and tensioning equipment must be isolated, insulated, or grounded.

11.I.45 A ground must be installed between the tensioning reel setup and the first structure to ground each bare conductor, sub-conductor, and overhead ground conductor during stringing operations.

11.I.46 During stringing operations, each bare conductor, sub-conductor, and overhead ground conductor must be grounded at the first tower adjacent to both the tensioning and pulling setup and in increments so that no point is more than 2 mi (3.2 km) from a ground.

1. The grounds must be left in place until conductor installation is complete.
2. These grounds must be removed as the last phase of aerial cleanup.
3. Except for moveable-type grounds, the grounds must be placed and removed with a hot stick.

11.I.47 Conductors, sub-conductors, and overhead ground conductors must be grounded at all dead-end or catch-off points.

11.I.48 A ground must be located at each side and within 10 ft (3 m) of working areas where conductors, sub-conductors, or overhead ground conductors are being spliced at ground level. The two ends to be spliced must be bonded to each other. Splicing should be carried out on either an insulated platform or a conductive metallic grounding mat bonded to both grounds. The grounding mat should be roped off and an insulated walkway provided for access to the mat.

11.I.49 All conductors, sub-conductors, and overhead ground conductors must be bonded to any isolated tower where it may be necessary to complete work on the transmission line.

1. Work on dead-end towers must require grounding on all de-energized lines.
2. Grounds may be removed as soon as the work is completed provided the line is not left open-circuited at the isolated tower at which work is being completed.

11.I.50 When performing work from the structure, clipping crews and all others working on conductors, sub-conductors, or overhead ground conductors must be protected by individual grounds installed at every workstation.

1. The voltage rating of the circuit on which the work is to be performed;
2. The clearances to ground of lines and other energized parts of which work is to be performed; and
3. The voltage limitations of the aerial-lift equipment intended to be used.

11.I.52 Only tools and equipment designed, tested, and intended for live-line bare-hand work must be used, and such tools and equipment must be kept clean and dry.

11.I.53 All work must be personally supervised by a person trained and qualified to perform live-line bare-hand work.

11.I.54 The automatic re-closing feature of circuit interrupting devices must be made inoperative where practical before working on any energized line or equipment.

11.I.55 Work must not be performed during electrical storms or when electrical storms are imminent.

11.I.56 A conductive bucket liner or other suitable conductive device must be provided for bonding the insulated aerial device to the energized line or equipment.

1. The employee must be connected to the bucket liner by conductive shoes, leg clips, or other suitable means; climbers must not be worn while performing work from an aerial lift.
2. Where necessary, electrostatic shielding for the voltage being worked or conductive clothing must be provided.

11.I.57 Before the boom is elevated, the outriggers on the aerial truck must be extended and adjusted to stabilize the truck. The body of the truck must be bonded to an effective ground or barricaded and considered as energized equipment.

11.I.58 Before moving an aerial lift into the work position, all controls (ground level and bucket) must be checked and tested to determine that they are in proper working condition.

11.I.59 Electrical insulating components and systems of aerial devices that are rated and used as an insulating device must be, after a thorough inspection of their condition and cleanliness, tested for compliance with their rating.

1. Tests must be conducted in accordance with the manufacturer's recommendations.
2. Tests must be conducted only by QPs who are knowledgeable of the hazards.

11.I.60 All aerial lifts to be used for live-line bare-hand work must have dual controls (ground level and basket).

1. The basket controls must be within easy reach of the employee in the basket. If a two-basket lift is used, access to the controls must be within easy reach from either basket.
2. The ground level controls must be located near the base of the boom and will permit override operation of equipment at any time.
3. Except in case of an emergency, ground level lift control must not be operated unless permission has been obtained from the employee in the lift. > See Section 11.I.57.

11.I.61 Before an employee contacts the energized part to be worked on, the conductive bucket liner must be bonded to the energized conductor by a positive connection that must remain attached to the energized conductor until the work on the energized circuit is completed.

11.I.62 The minimum clearances for live-line bare-hand work must be as specified in Table 11-3.

1. These minimum clearances must be maintained from all grounded objects and from lines and equipment at a different potential than that to which the insulated aerial device is bonded, unless such grounded objects or other lines and equipment are covered by insulated guards.
2. These distances must be maintained when approaching, leaving, and when bonded to the energized circuit.
3. When approaching, leaving, or bonding to an energized circuit, the minimum distances in Table 11-3 must be maintained among all parts of the insulated boom assembly and any grounded parts (including the lower arm or portions of the truck).
4. When positioning the bucket alongside an energized bushing or insulator string, the minimum line-to-ground clearances of Table 11-3 must be maintained among all parts of the bucket and the grounded end of the bushing or insulator string.
5. A minimum clearance table (as in Table 11-3) must be printed on a plate of durable nonconductive material and mounted in the bucket or in its vicinity so as to be visible to the boom operator.
6. Only insulated measuring sticks must be used to verify clearance distances.

11.I.63 Handlines between buckets, booms, and the ground are prohibited.

1. Conductive materials more than 36 in (1 m) long must not be placed in the bucket, except for appropriate length jumpers, armor rods, and tools.
2. Non-conductive handlines may be used from line to ground when not supported from the bucket.

11.I.64 The bucket and boom must not exceed the manufacturer's rated capacity while attempting to lift or support additional load.

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