Omid Giahi1, Ebrahim Darvishi1, Mohsen Aliabadi2, Jamshid Khoubi1. 1. Department of Occupational Hygiene, Faculty of Public Health and Kurdistan Environmental Health Research Center, Kurdistan University of Medical Sciences, Sanandaj, Iran. 2. Department of Occupational Hygiene, Faculty of Public Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, Iran.
Abstract
BACKGROUND: Workers' exposure to excessive heat in molten industries is mainly due to radiant heat from hot sources. OBJECTIVE: The aim of this study was to evaluate the efficacy of radiant heat controls on workers heat stress around a typical blast furnace. METHODS: Two main interventions were applied for reducing radiant heat around the blast furnace of a steel industry located in western Iran. These included using a heat absorbing system in the furnace body and installing reflective aluminum barrier in the main workstation. Heat stress indexes were measured before and after each intervention using the digital WBGT-meter. RESULTS: The results showed MRT and WBGT indexes decreased by 20 °C and 3.9 °C, respectively after using heat absorbing system and also decreased by 18.6 °C and 2.5 °C, respectively after installing a reflective barrier. These indexes decrease by 26.5 °C and 5.2 °C, respectively due to the simultaneous application of the two interventions which were statistically significant (p < 0.001). The core body temperature of workers decreased by 2.6 °C after the application of interventions which was also significant (p < 0.05). CONCLUSIONS: The results confirmed heat control at source can be considered as a first solution for reducing radiant heat of blast furnaces. However, the simultaneous application of interventions could noticeably reduce worker heat stress. The results provide reliable information in order to implement the effective heat controls in typical hot steel industries.
BACKGROUND: Workers' exposure to excessive heat in molten industries is mainly due to radiant heat from hot sources. OBJECTIVE: The aim of this study was to evaluate the efficacy of radiant heat controls on workers heat stress around a typical blast furnace. METHODS: Two main interventions were applied for reducing radiant heat around the blast furnace of a steel industry located in western Iran. These included using a heat absorbing system in the furnace body and installing reflective aluminum barrier in the main workstation. Heat stress indexes were measured before and after each intervention using the digital WBGT-meter. RESULTS: The results showed MRT and WBGT indexes decreased by 20 °C and 3.9 °C, respectively after using heat absorbing system and also decreased by 18.6 °C and 2.5 °C, respectively after installing a reflective barrier. These indexes decrease by 26.5 °C and 5.2 °C, respectively due to the simultaneous application of the two interventions which were statistically significant (p < 0.001). The core body temperature of workers decreased by 2.6 °C after the application of interventions which was also significant (p < 0.05). CONCLUSIONS: The results confirmed heat control at source can be considered as a first solution for reducing radiant heat of blast furnaces. However, the simultaneous application of interventions could noticeably reduce worker heat stress. The results provide reliable information in order to implement the effective heat controls in typical hot steel industries.