Heat illness in the U.S. mining industry

Abstract

Background: Heat illness is relatively common in the underground metalliferous mines of South Africa and Australia. Little is known about heat illness in other forms of mining and there have been no studies of heat illness in the US mining industry.

Methods: Mine Safety and Health Administration (MSHA) accident, injury, illness, and employment data were used to study heat illness reported by the US mining industry from January 1, 1983 to December 31, 2001.

Results: Five hundred thirty eight cases of heat illness were reported. None of these cases were fatal. Four hundred twenty seven cases (79.4%) occurred in the summer months of June, July, and August. Incidence rates of heat illness in underground mining ranged from 0.00275/10(6) person-hours for coal, to 0.168/10(6) person-hours for metal, rate-ratio = 61.1 (P < 0.001). Incidence rates in surface mining ranged from 0.0265/10(6) person-hours for coal, to 0.0644/10(6) person-hours for stone, rate-ratio = 2.43 (P < 0.001). Incidence rates in mills/preparation plants ranged from 0.0255/10(6) person-hours for coal, to 0.417/10(6) person-hours for stone, rate-ratio = 16.4 (P < 0.001).

Conclusions: Heat illness occurs most frequently in stone mills, metal mills, and underground metal mines. Preventive measures should target the summer months of June, July, and August.