Pennsylvania Statutes Title 52 P.S. Mines and Mining § 70-710. Operator or superintendent to provide telephones

The operator or superintendent of any coal mine or colliery which is worked by shaft, slope or plane, shall provide and maintain a telephone, or suitable appliance by or through which conversation can be held by and between persons at each shaft landing and slope or plane lift and at the top of the shaft, slope or plane, and also an efficient means of signaling from each shaft landing, slope or plane lift to the engineer in charge of the hoisting engine. The operator or superintendent of every coal mine or colliery shall provide and maintain a telephone by or through which conversation can be had between persons on the outside of the mines and each working section that is fifteen hundred feet or more from the outside.