Blasting injuries in surface mining with emphasis on flyrock and blast area security

Abstract

Problem: Blasting is a hazardous component of surface mining. Serious injuries and fatalities result from improper judgment or practice during rock blasting. This paper describes several fatal injury case studies, analyzes causative factors, and emphasizes preventive measures. Method: This study examines publications by MSHA, USGS, and other authors. The primary source of information was MSHA's injury-related publications. Results: During the 21-year period from 1978 to 1998, the mean yearly explosive-related injuries (fatal and nonfatal) for surface coal mines was 8.86 (95% CI: 6.38–11.33), and for surface metal/nonmetal mines 10.76 (95% CI: 8.39–13.14). Flyrock and lack of blast area security accounted for 68.2% of these injuries. This paper reviews several case studies of fatal injuries. Case studies indicate that the causative factors for fatal injuries are primarily personal and task-related and to some extent environmental. A reduction in the annual injuries in surface coal mines was observed during the 10-year period of 1989–1998 [5.80 (95% CI: 2.71–8.89) compared to the previous 10-year period of 1979–1988 [10.90 (95% CI: 7.77–14.14)]. However, such reduction was not noticed in the metal/nonmetal sector (i.e., 9.30 [95% CI: 6.84–11.76] for the period 1989–1998 compared with 11.00 [95% CI: 7.11–14.89] for the period 1979–1988). Discussion: A multifaceted injury prevention approach consisting of behavioral/educational, administrative/regulatory, and engineering interventions merits consideration. Impact on industry: The mining community, especially the blasters, will find useful information on causative factors and preventive measures to mitigate injuries due to flyrock and lack of blast area security in surface blasting. Discussion of case studies during safety meetings will help to mitigate fatal injuries and derive important payoffs in terms of lower risks and costs of injuries.