(a) Air regulation of all slopes, drifts, or shafts used for hoisting or hauling coal shall be made at the intake of air into the mine, except at the option of the owner or by direction of the State Mine Inspector, and all air that goes into the mine shall be so split that not more than fifty (50) employees will be working on each split of air, and not less than two hundred cubic feet (200 cu. ft.) of air per person shall pass each working face per minute, and the air shall be sufficient to dilute all noxious or explosive gases.
(b) It shall be the duty of the mine inspector to measure the air at all working faces in making his or her inspection.
(c) The machinery and appliances used for conducting or driving the air into the mines shall be so installed, arranged, and adjusted that the air currents may be easily and speedily reversed in emergencies.