Factors associated with heat strain among workers at an aluminum smelter in Texas.

Abstract

To determine the prevalence of heat strain and factors associated with heat strain among workers at an aluminum smelter in Texas. Continuous core body temperature (T(c)), heart rate, and pre- and postshift serum electrolytes, and urine specific gravity were measured, and symptom questionnaires were administered. Most participants (54%) had 1 or more signs of heat strain. Unacclimatized participants were significantly more likely to exceed the American Conference of Governmental Industrial Hygienists-recommended T(c) than acclimatized participants (88% vs 20%; P < 0.01). Participants who exceeded the T(c) for their acclimatization status and/or exceeded the recommended sustained peak HR had a significantly lower body mass index than those who did not (27.6 vs 31.8 and 28.4 vs 32.4, respectively; P = 0.01). Employees and management need to strictly adhere to a heat stress management program to minimize heat stress and strain.