Center for the Built Environment

Industrial workers in hot and humid environments are vulnerable to heat stress, especially in facilities where mechanical cooling can be expensive and/or impractical to install and operate. We assessed whether air movement from fans can effectively reduce heat strain and improve thermal comfort in an un-airconditioned manufacturing facility in Baton Rouge, (Louisiana, USA). Over six weeks, thirty workers were monitored under alternating fan-on and fan-off conditions. Physiological, environmental, and survey data were collected to evaluate comfort, perceived performance, thermal stress and physiological strain. Results show that fans significantly reduced discomfort and the level of perceived effort equivalent to a 5°C reduction in temperature. All the workers stated that having fans in the workplace was important to them and 79% felt that they were more effective at their job with the fans running. Sublingual temperature, heart rate and sweat rate increased with ambient temperature, but did not differ with or without the electric fans. These findings show that air movement offers a low-cost, energy-efficient and effective strategy to mitigate worker discomfort and perceived level of effort and it does not worsen physiological indicators of heat stress in hot manufacturing environments.