225 ILCS 705/21.08

Welding, cutting and soldering with arc or flame underground, in other than a fireproof enclosure is permitted but it shall be done under the direct supervision of competent personnel, who shall test for methane gas before and during such operations in gassy mines, and shall make a diligent search for fire after such operations in all mines. Rock dust or suitable fire extinguishers shall be immediately available during such welding, cutting or soldering.