Section 57.22104 - Open flames (I-C mines)(a) Open flames, including cutting and welding, shall not be used underground.(b) Welding and cutting shall not be done within 50 feet of a mine opening unless all persons are out of the mine and the mine opening is covered. The cover shall be a substantial material, such as metal or wood, topped with a layer of wetted material to prevent sparks and flames from entering the mine opening.