Pennsylvania Statutes Title 52 P.S. Mines and Mining § 690-329. Locomotives

(a) Electric haulage.--Electric haulage by trolley locomotive is not permitted except on intake air.

(b) Certain operation prohibited.--It shall be unlawful to run or operate a locomotive, fed directly or indirectly from a trolley wire, by the open entrances to worked out places wherein the pillars have been drawn or places in which the pillars have not been drawn but in places where the roof has collapsed.

(c) Certain use proscribed.--No open-type electric locomotive or open-type electric machine of whatsoever type shall be taken into a working place. Main return airways or passageways shall not be used as haulageways for electric locomotives operated from a trolley wire.