ARLINGTON, Va. (AP) — Federal mine safety regulators issued more than 190 citations during special impact inspections at U.S. mines in September.

The U.S. Mine Safety and Health Administration says that the inspections at nine coal mines and four other mines resulted in 192 citations and five orders. The citations included accumulations of combustible materials and unguarded belt conveyors.

Monthly impact inspections began in 2010 after the Upper Big Branch mine explosion in West Virginia killed 29 miners. Since then, 823 inspections have been conducted at coal, metal and nonmetal mines, resulting in a total 13,140 citations and 1,194 orders.

The increased enforcement is conducted at mines that have a poor compliance history or specific compliance concerns.

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