Electrical accidents in the mining industry, 1990-1999

This National Institute for Occupational Safety and Health study was conducted to focus future research on the most significant electrical problems in the mining industry. Data from 1,926 mine electrical accidents (including 75 fatalities) that occurred between 1990 and 1999 were studied. Coal and metal-nonmetal operator- and contractor-reported data are presented. All data used in this analysis were MSHA closeout data, except 1999, which were preliminary data. Electricity was the 4th leading cause of death reported in mining despite being the 14th leading cause of injuries. During the 1990s, 1 of every 272 mining accidents resulted in a fatality. In comparison, 1 of every 26 mine electrical accidents was fatal. Burns were the leading Nature of Injury in electrical accidents, but were rarely fatal. Electrical shock caused 70 of the 75 electrical fatalities reported. About one-half of mine electrical accidents and fatalities were sustained during electrical maintenance. Small mines experience a disproportionately high number of electrical accidents and fatalities based on total average employment. The injury severity for victims of nonfatal mine electrical injuries does not increase with age in victims 50 years and older, unlike many other types of occupational accidents. High-reaching mobile equipment is involved in about 20% of mine electrical fatalities, indicating that overhead power line hazards need to be addressed. Electrical accident narratives containing the six most frequently mentioned keywords were isolated for further analysis. 1,321 narratives containing the keywords "breaker", "cable","battery","ground","energized" and "meter" were analyzed to more accurately determine causal factors. Technical suggestions for mitigating electrical hazards are proposed.