MSHA Issues Serious Accident Alert for Fly Rock

The Mine Safety and Health Administration (MSHA) issued a new Serious Accident Alert. On Dec. 11, 2017, miners were preparing for a shot. The miners were positioned about 130 yd. from the face.

One miner was standing between a pickup truck and an excavator; the other two were under the excavator. The shot detonated prematurely, without warning. The miners were struck with debris resulting in injuries.

MSHA recommends the following best practices to avoid accidents like these:

  • Consider mine specific conditions and rock strata when designing blasts to prevent fly rock.
  • Closely follow mine policies and procedures through all phases of the blasting operation.
  • Schedule blasting between shifts or on off-shifts.
  • Utilize suitable blast shelters for all persons at the mine site during blasting.
  • Use restricted areas for non-enclosed blasting operations.
  • Keep coworkers away from the blaster.
  • Always consider past "fly rock" when determining your blast area and your blast area should as a minimum be 1.5 times the furthest distance that any previous fly rock has traveled.