52 Pa. Stat. § 70-117
Each mine inspector shall devote the whole of his time to the duties of his office. They shall examine all the mines and collieries of their district at last once every two months and as often, in addition thereto, as the Secretary of Mines and Mineral Industries may direct or the necessities of the case or the condition of the mines require. They shall see that every necessary precaution is taken to secure the safety of the workmen, and that the provisions of this act are observed and obeyed; and they shall personally visit each active working-face and the face of each place where work has progressed since the last inspection and see that the air current is carried to the active and inactive working-faces, and is of sufficient quantity or volume to thoroughly ventilate the places. They shall, within fifteen days after every inspection, make a report of the condition of each active and inactive face visited in each colliery, on a form to be furnished to the inspectors by the Secretary of Mines and Mineral Industries designating, as they appear on the maps of the mine inspector and mine operator, the gangway title in which the working is situated and the breast number of said working and their condition shall be designated in clear, specific, descriptive language (use of generic words such as good, fair or bad are not deemed to be specific) and shall note any action that may be taken. The report shall show the date of the inspection, the number of cubic feet of air measured at the intake for each split, the number of persons employed in each split of air together with such information as the secretary may deem necessary. Where there are multiple shifts the mine inspector shall so arrange his inspection work to insure that a part of the inspection falls on each operating shift.
52 P.S. § 70-117