No person shall operate any crane, derrick, power shovel, drilling rig, pile driver, hoisting equipment, or similar apparatus, or any part thereof, which could be brought within ten (10) feet of any high voltage overhead line, unless:
There is posted and maintained a warning sign, as herein defined, clearly legible and placed as follows:
Within the equipment readily visible to the operator of such equipment when at the controls of such equipment; and
On the outside of the equipment in such number and location as to be readily visible to mechanics or other persons engaged in the work operations;
There is installed an insulated cage-type guard or protective device about the boom or arm of all equipment, except backhoes or dippers and, where the equipment includes a lifting hook device, all lifting lines are equipped with insulator links on the lift hook connection; and
A person is designated to observe clearance of the equipment from any nearby high voltage overhead lines and to give timely warning for all operations where it is difficult by visual means for the operator to determine and to maintain the required clearance.