WAC 296-32-360   Tree trimming -- Electrical hazards.  (1) General.

     (a) Employees engaged in pruning, trimming, removing, or clearing trees from lines shall 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.

     (b) Employees engaged in line-clearing operations shall 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.

     (c) Before any work is performed in proximity to energized conductors, the system operator/owner of the energized conductors shall 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 electrical hazards.

     (a) Employers shall 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 shall 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) Only employees or trainees, familiar with the special techniques and hazards involved in line clearance, shall be permitted to perform the work if it is found that an electrical hazard exists.

     (c) During all tree working operations aloft where an electrical hazard of more than 750 volts exists, there shall be a second employee or trainee qualified in line clearance tree trimming within normal voice communication.

     (d) Where tree work is performed by employees qualified in line-clearance tree trimming and trainees qualified in line-clearance tree trimming, the clearances from energized conductors given in Table 2 shall apply.

TABLE 2

Minimum Working Distances From Energized Conductors For Line-

Clearance Tree Trimmers and Line-Clearance Tree-Trimmer Trainees
Voltage Range

(Phase to Phase)

(kilovolts)		 Minimum

Working

Distance		  
2.1 to 15.0 ——————————————— 2 ft. 0 in.  
15.1 to 35.0 ——————————————— 2 ft. 4 in.  
35.1 to 46.0 ——————————————— 2 ft. 6 in.  
46.1 to 72.5 ——————————————— 3 ft. 0 in.  
72.6 to 121.0 ——————————————— 3 ft. 4 in.  
138.0 to 145.0 ——————————————— 3 ft. 6 in.  
161.0 to 169.0 ——————————————— 3 ft. 8 in.  
230.0 to 242.0 ——————————————— 5 ft. 0 in.  
345.0 to 362.0 ——————————————— 7 ft. 0 in.  
500.0 to 552.0 ——————————————— 11 ft. 0 in.  
700.0 to 765.0 ——————————————— 15 ft. 0 in.  

     (e) Branches hanging on an energized conductor may only be removed using insulated equipment by a qualified electrical worker.

     (f) Rubber footwear, including lineman's overshoes, shall not be considered as providing any measure of safety from electrical hazards.

     (g) Ladders, platforms, and aerial devices, including insulated aerial devices, shall not be brought in contact with an electrical conductor. Reliance shall not be placed on their dielectric capabilities.

     (h) When an aerial lift device contacts an electrical conductor, the truck supporting the aerial lift device shall be considered as energized.

     (3) Storm work and emergency conditions.

     (a) Since storm work and emergency conditions create special hazards, only authorized representatives of the electric utility system operator/owner and not telecommunication workers may perform tree work in these situations where energized electrical power conductors are involved.

     (b) When an emergency condition develops due to tree operations, work shall be suspended and the system operator/owner shall be notified immediately.



[Statutory Authority: Chapter 49.17 RCW. 94-15-096 (Order 94-07), § 296-32-360, filed 7/20/94, effective 9/20/94; Order 76-38, § 296-32-360, filed 12/30/76; Order 75-41, § 296-32-360, filed 12/19/75.]