April 10, 2018
The Mine Safety and Health Administration (MSHA) issued a Serious Accident Alert after two miners were injured in an explosion. On March 24, 2018, two miners at a Fred Weber underground quarry in Missouri were using a man-lift to charge (load) blast holes with non-electric blasting caps, 8-grain boosters, and ammonium nitrate fuel oil (ANFO) blasting agent. During the loading process, one of the non-electric shock-tubes became wedged on the man-lift basket. As the man-lift operator progressed across the face loading the blast holes, the wedged-shock tube stretched and broke (snapped), causing a pre-detonation of a blast hole. As a result of the pre-detonation, one miner received minor injuries, and the other miner received serious injuries.
MSHA offers the following Best Practices to help prevent this type of accident: