Underground/buried communication lines.

(1) No employer shall permit an employee to work in such proximity to any part of an electric power circuit that the employee could contact the electric power circuit in the course of work, unless the employee is protected against electric shock by deenergizing the circuit and grounding it or by guarding it effectively by insulation or other means.

(2) No person, firm, corporation, or agent of same, shall require or permit any employee to perform any function in proximity to electrical conductors or to engage in any excavation, construction, demolition, repair, or other operation, unless and until danger from accidental contact with said electrical conductors has been effectively guarded by deenergizing the circuit and grounding it or by guarding it by effective insulation or other effective means.

(3) In work areas where the exact location of underground electric powerlines is unknown, no activity which may bring employees into contact with those powerlines must begin until the powerlines have been positively and unmistakably deenergized and grounded.

(4) Before work is begun the employer must ascertain by inquiry or direct observation, or by instruments, whether any part of an energized electric power circuit, exposed or concealed, is so located that the performance of the work may bring any person, tool, or machine into physical or electrical contact with the electric power circuit. The employer must post and maintain proper warning signs where such a circuit exists. The employer must advise employees of the location of such lines, the hazards involved, and the protective measures to be taken.