§873 Blasting and Explosives

Summary

Black blasting powder may not be stored or used underground, and loose open shots like mudcaps may not be fired underground. Explosives and detonators must be kept in separate containers until right before a blast. In anthracite mines, mudcaps or other open shake shots can be used only for starting a battery or taking down loose coal when it is too dangerous to use other methods, and only if no methane or fire hazard is present. A methane test must be done just before such a shot, and the shot cannot be made if methane is 1.0 volume percent or higher until it drops below 1.0. Only approved (permissible) explosives, detonators, and blasting devices may be used in underground coal areas and must be fired with approved shot-firing units. Boreholes must be stemmed with noncombustible material. The Secretary may allow more than twenty shots or nonapproved explosives when sinking shafts or slopes from the surface in rock under safeguards. Explosives and detonators carried underground must be in closed, nonconductive containers in good condition and transported only in special closed containers on approved mine equipment. When stored underground, supplies must be in sturdy section boxes or magazines with no exposed metal inside, at least 25 feet from roadways and power wires, dry, rock-dusted, and protected from roof falls (or in niches cut into solid coal/rock where needed). In working places, explosives and detonators must be in separate closed containers, out of the blast line, at least 50 feet from the working face and 15 feet from pipelines, powerlines, rails, or conveyors (or 5 feet if in rib niches), and kept at least 5 feet apart from each other.