Roof control in underground mines involves securing the top as well as the sides of travel ways, or walls, which are referred to as “ribs.” The number of injuries resulting from roof and rib failures increased from 439 in 2010 to 484 in 2011. In 2010, the number of fatal rib failure accidents (in which the walls in the underground mine crumble from pressure) exceeded the number of typical roof fall accidents (where the roof falls from the top of the mine) for the first time ever, by a margin of one. In 2011, fatal rib failure accidents again outnumbered fatal roof fall accidents by one.

“Rib failures pose as much of a danger as the more typical roof fall accidents, and this tragic death was a telling example,” said Joseph A. Main, assistant secretary of labor for mine safety and health. “We are concerned that there was only a slight decrease in fatalities from these accidents between 2010 and 2011, and we are even more concerned about the increase last year in the number of miners who were injured in these accidents. Clearly, we must reinvigorate our efforts to educate mine operators and miners about ways to alleviate hazards.”

Because improper examinations of roof and rib conditions often lead to deadly roof and rib failure accidents that can be avoided, MSHA will distribute specific information to underground mine operators and miners about these dangers, as well as methods to thoroughly check and address hazardous roof and rib conditions.

During the annual roof control initiative, MSHA inspectors also will distribute informational posters that identify rib control problems and list several possible solutions. The materials are available at: