WAC 296-54-529. Overhead electrical lines clearance

One of the following conditions must exist in work areas where equipment or machines are operated near electrical distribution and transmission lines: (1) The lines have been deenergized and visibly grounded at the point of work; (2) Insulating barriers that are not a part of or an attachment to the equipment or machinery are erected to prevent physical contact with the lines; or (3) All of the following requirements are met: Line Voltage Required minimum clearance between lines and any part of equipment or machine (a) 50 kV or below ten feet (b) over 50 kV ten feet plus 0.4 inch for each 1 kV over 50 kV, or twice the length of the line insulator, but never less than ten feet For equipment or machinery in transit with no load and any boom or extended equipment lowered: (c) 50 kV or below four feet (d) 50-345 kV ten feet (e) 345-750 kV sixteen feet Line Voltage Required minimum clearance between lines and any part of equipment or machine (a) 50 kV or below ten feet (b) over 50 kV ten feet plus 0.4 inch for each 1 kV over 50 kV, or twice the length of the line insulator, but never less than ten feet For equipment or machinery in transit with no load and any boom or extended equipment lowered: (c) 50 kV or below four feet (d) 50-345 kV ten feet (e) 345-750 kV sixteen feet (4) Someone must be designated to observe proper clearance and to give timely warning for all operations where it is difficult for the operator to see well enough to maintain the clearance. (5) All overhead wires must be considered energized unless the line owner or the electrical utility authorities ensure that it is not an energized line and has been visibly grounded. (6) Special precautions must be taken to prevent trees from falling into power lines. You must notify the power company immediately if a felled tree makes contact with any power line. Before falling any tree that appears will hit a power line, the employer must notify the power company. If a tree does contact a power line, all employees must remain clear of the area until the power company ensures that there is no electrical hazard.