2010 Copiapó mining accident San Jose Mine were around 20% higher than at other Chilean mines due to its poor safety record. The collapse occurred at 14:00 CLT on 5 August 2010. Access to the depths of the mine was by a long helical roadway. A group nearer the entrance escaped, but a second group of 33 men were trapped deep inside. A thick dust cloud caused by the rock fall blinded the miners for as much as six hours. Initially, the trapped miners tried to escape through ventilation shafts, but the ladders required by safety codes were missing. Luis Urzúa, the duty shift
Ontario Mine Rescue to allow for a four-hour capability. The BG174 proved a workhorse for almost 40 years before it was replaced by the BG4. Ontario Mine Rescue took on added responsibility in 1984 after four miners were trapped and killed in a rockburst at Falconbridge No. 5 Shaft near Sudbury. The Stevenson Commission recommended that the organization's mandate be expanded to conduct training in and respond to non-fire emergencies. Training on non-fire rescue equipment began shortly after. In January 2001, responsibility for Ontario Mine Rescue was transferred to the Mines and Aggregates Safety and Health Association, now a part of Workplace Safety