(1) General.
(a) Employees engaged in pruning, trimming, removing, or clearing trees from lines must be required to consider all overhead and underground electrical power conductors to be energized with potentially fatal voltages, never to be touched (contacted) either directly or indirectly and comply with Table 7 of this section for minimum approach distances.
(b) Line clearance tree trimming operations exposing employees to electrical hazards must be addressed by qualified line clearance tree trimmers covered under chapter
296-45 WAC.
(c) Employees engaged in line-clearing operations must be instructed that:
(i) A direct contact is made when any part of the body touches or contacts an energized conductor, or other energized electrical fixture or apparatus.
(ii) An indirect contact is made when any part of the body touches any object in contact with an energized electrical conductor, or other energized fixture or apparatus.
(iii) An indirect contact can be made through conductive tools, tree branches, truck equipment, or other objects, or as a result of communications wires, cables, fences, or guy wires being accidentally energized.
(iv) Electric shock will occur when an employee, by either direct or indirect contact with an energized conductor, energized tree limb, tool, equipment, or other object, provides a path for the flow of electricity to a grounded object or to the ground itself. Simultaneous contact with two energized conductors will also cause electric shock which may result in serious or fatal injury.
(d) Before any work is performed in proximity to energized conductors, the system operator/owner of the energized conductors must be contacted to ascertain if they know of any hazards associated with the conductors which may not be readily apparent. This rule does not apply when operations are performed by the system operator/owner.
(2) Working in proximity to potential electrical hazards.
(a) Employers must ensure that a close inspection is made by the employee and by the crewleader or supervisor in charge before climbing, entering, or working around any tree, to determine whether an electrical power conductor passes through the tree, or passes within reaching distance of an employee working in the tree. If any of these conditions exist either directly or indirectly, an electrical hazard must be considered to exist unless the system operator/owner has caused the hazard to be removed by deenergizing the lines, or installing protective equipment.
(b) Qualified line clearance tree trimmers or trainees must comply with Table 7 below:
Table 7
Minimum Working Distances from Energized Conductors for Line-
Clearance Tree Trimmers and Line-Clearance Tree-Trimmer Trainees
Voltage in Kilovolts Phase-to-Phase or Phase-to-Ground | Distance to Employee Phase-to-Phase or Phase-to-Ground (ft-in) |
0 to 0.050 | Not Specified |
0.051 to 0.300 | Avoid Contact |
0.301 to 0.750 | 1-6 |
0.751 to 15 | 3-0 |
15.1 to 36.0 | 3-6 |
36.1 to 46.0 | 4-0 |
46.1 to 72.5 | 4-6 |
Voltage in Kilovolts Phase-to-Phase or Phase-to-Ground | Distance to Employee from Energized Part Without Tools Phase-to-Phase or Phase-to-Ground (ft-in) |
72.6 to 121 | 5-6 |
121.1 to 145 | 6-6 |
145.1 to 169 | 7-0 |
169.1 to 242 | 10-6 |
242.1 to 362 | 15-6 |
362.1 to 420.0 | 18-4 |
420.1 to 550.0 | 22-0 |
550.1 to 800.0 | 27-9 |
(c) Rubber footwear, including lineman's overshoes, must not be considered as providing any measure of safety from electrical hazards.
(d) Ladders, platforms, and aerial devices, including insulated aerial devices, may not be brought in contact with an electrical conductor. Reliance must not be placed on their dielectric capabilities.
(e) When an aerial lift device contacts an electrical conductor, the truck supporting the aerial lift device must be considered as energized.