§ 33.71. Calcium carbide.

 (a)  Storage. All calcium carbide, except as specified in subsection (b), shall be stored outside the mine in detached, waterproof, dry and well ventilated sheds or buildings so located that any gases or fumes from such calcium carbide cannot in any manner be drawn into the air inlets even when the air current is reversed. Calcium carbide shall be stored in the original metal containers. All the metal containers in any one storage place other than the one from which individual supplies are being taken, shall be kept sealed, except that a new container may be opened when the amount of carbide in the container already open is less than one pound.

 (b)  Daily supply. Nothing in this subchapter shall be construed to prohibit the erection and maintenance of approved carbide holders or filling stations, either inside or outside the mine, used for the purposes of filling cadgers or other containers with an amount of carbide sufficient to supply one person for work for 1 day. Approved carbide holders or filling stations shall be constructed of metal and shall be fully enclosed. If carbide is used inside a mine, a supply sufficient to fill all cadgers for the work of one day may be maintained. No person shall be permitted to take into a mine an amount of calcium carbide greater than that necessary for one working day. The supplies shall be kept in metal waterproof boxes. The amount necessary for one working day shall be construed to mean the amount used in one day by one man or as many men in addition as may be employed in one gang or in one work place.

 (c)  Cleaning tables. Tables used for cleaning and refilling carbide lamps shall not be located inside the mine. They shall be so located outside the mine that no gases or fumes emanating from them are in any manner drawn into the air inlets of the mine even when the air current is reversed. Nothing in this subchapter shall be construed to prohibit the use of a small table in the outlet airway at the entrance of a mine where employes, when leaving the mine, may empty the used carbide from their lamps.