Sec. 924. [Ventilation of mines while persons working therein.] At each mine where the ventilation is not continuous, it shall be started a sufficient length of time prior to the appointed time for any person, or persons, working therein to enter, to clear the mine of explosive, poisonous and noxious gases, and shall be kept in operation a sufficient length of time after the appointed time for such employes to leave their working places, for all persons to be out of the mine. ([Sec. 922], [923], [952]; Penalty, [Sec. 976].)
[Pressure gauges.] At each mine generating fire-damp so as to be detected by a safety lamp, and wherein twenty or more persons are employed, a recording pressure gauge for the purpose of recording the pressure or vacuum of the main air current, shall be provided and maintained, which shall be kept in constant use, and records preserved for ninety days, subject to the inspection of the chief inspector of mines and the district inspector of mines. (Penalty, [Sec. 976].)
Sec. 925. [Competent person or persons shall be designated as fire-boss.] The owner, lessee or agent of a mine generating fire-damp so as to be detected by a safety lamp, shall designate a competent person or persons as fire boss or fire bosses, who shall make a thorough examination of each working place in the mine every morning with a standard safety lamp, not more than three hours prior to the appointed time for the employes to enter the mine. As evidence of such examination, the fire boss shall mark with chalk upon the face of the coal, or in some other conspicuous place, his initials and date of the month upon which the examination is made. If there is any standing gas discovered, he must leave a danger signal across every entrance to such place.
[Examination of other than working places.] Each mine generating fire-damp so as to be detected by a safety lamp, shall be kept free from standing gas. All traveling ways, entrances to old workings, and places not in the actual course of working, shall be carefully examined with a safety lamp by the fire boss not more than three hours before the appointed time for persons employed therein to enter. Parts of the mine not in the actual course of working and available, shall be examined not less than once each three days, and shall be so fenced as to prevent persons from inadvertently entering therein. ([Sec. 955], [959]; Penalty, [Sec. 976].)
Sec. 926. [Breakthroughs and brattices.] From a point where the seam is reached in the opening of a mine, to a point not exceeding a distance of four hundred feet therefrom, breakthroughs shall be made between main entries, where there are no rooms worked, not more than one hundred feet apart, provided such entries are not advanced beyond the point where the breakthrough will be made until the breakthrough is complete. Breakthroughs between entries, except as hereinbefore provided, shall be made not exceeding sixty feet apart. Where there is a solid block on one side of a room, breakthroughs shall be made between such room and the adjacent room not to exceed sixty feet apart; where there is a breast or group of rooms, a breakthrough shall be made on one side or the other of each room, except the room adjoining said block, not to exceed forty feet from the outside corner of the breakthrough to the nearest corner of the entrance to the room, and on the opposite side of the same room a breakthrough shall be made, not to exceed eighty feet from the outside corner of the breakthrough to the nearest corner of the entrance to the room, and thereafter breakthroughs shall be made not to exceed eighty feet apart on each side of the room. No working place, except those provided for within a distance of four hundred feet of the principal openings of a mine, shall be driven more than eighty feet in advance of a breakthrough or air-way. The required air current shall be conducted to the breakthrough nearest the face of such entry or room. All breakthroughs between entries, and when necessary between rooms, except the one nearest the working face, shall be closed and made air-tight by brattice, trap doors or other means, so that the current of air in circulation may sweep to the interior of the mine. Brattices between permanent inlet and outlet airways shall be constructed in a substantial manner of brick, masonry, concrete, or non-perishable material. In mines generating fire-damp, so as to be detected by a safety lamp, the air current shall be conducted by brattice, or other means, near enough to the working face to expel the fire-damp, and prevent the accumulation of the same. (Penalty, [Sec. 976].)
Sec. 927. [Safe appliances for hoisting persons.] The owner, lessee or agent of a mine shall provide and maintain safe appliances, approved by the district inspector of mines, for the ingress and egress of persons in each shaft, designated by such owner, lessee or agent as a means of ingress and egress for persons employed therein. When there is but one shaft available for ingress and egress from any unavoidable cause, the appliances therein shall be kept available to persons therein employed at all times. When such appliances in any shaft are rendered unavailable from any cause, the same shall be restored without delay.
[Emergency appliances.] When the only means of egress is by vertical shaft, in which cages or elevators are used as a means of hoisting persons therein employed, and the power for operating same is derived from but one source, the owner, lessee or agent shall provide and keep on hand for use in the event of an accident to the hoisting apparatus or the power by which same is operated, a suitable windlass, capable of hoisting the persons from the mine.
[Competent engineers.] The owner, lessee or agent of a mine worked by a shaft or slope, shall put in charge of an engine used for lowering into or hoisting out of such mine persons employed therein, only experienced, competent and sober engineers. ([Sec. 916], [928]; Penalty, [Sec. 976].)
Sec. 928. [Metal speaking tube and safety appliances.] The owner, lessee or agent of a mine operated by shaft, shall provide and maintain a metal tube suitable for conversation between persons, connecting the engine room with the top and bottom of such shaft; an approved safety catch, a sufficient cover, and rings or other adequate handholds for ten persons, on all cages used for lowering and hoisting persons: Such cages to be protected on each side by a boiler plate not less than one-fourth inch in thickness, and not less than three feet high, and shall provide an approved safety gate at the top of each shaft, an adequate brake to control the drum used for lowering or hoisting persons in shafts or slopes, and an indicator on all machines used for such purpose, to show the location of cages in shaft or slope. No cage having an unstable or self-dumping platform shall be used for the carriage of persons unless such platform is securely locked. ([Sec. 916], [927]; Penalty, [Sec. 976].)
Sec. 929. [Hoisting and lowering of persons.] The owner, lessee or agent of a mine, at which the only means of ingress and egress for the persons employed therein is by a vertical shaft or shafts, of fifty feet or more in depth, shall designate one or more persons whose duty shall be to attend to the lowering and hoisting of persons into and out of such mine, and give and receive the proper signals, governing the movement of the cage while engaged in handling men. Not more than ten persons shall be lowered or hoisted at any one time. The lowering of persons shall begin in time for persons to reach their working places by hour appointed for mine to commence work and continue until starting time. Hoisting of persons shall commence at time for mine to cease work, and continue until all have had time to be hoisted. Persons may be hoisted at such other times as will not interfere with the hoisting of coal, or other products. No person shall be lowered into or hoisted out of a mine, with powder, explosives, tools or material on any cage, in the same shaft, and no person shall be lowered or hoisted in a vertical shaft in a mine car. When the vertical shaft is less than fifty feet in depth, and a stairway approved by the district inspector of mines is not provided, the owner, lessee or agent shall be required to lower or hoist persons, as above prescribed, but when such stairway is provided, the hoisting of persons shall not be required.