Comparing the physiological and perceptual responses of construction workers (bar benders and bar fixers) in a hot environment

Abstract

Highlights We found that, in a hot environment, physical workload (in terms of energy expenditure) of rebar work is: overall rebar work (2.57Kcal/min), bar bending (2.26Kcal/min) and bar fixing (2.67Kcal/min). Bar fixing induced significantly higher physiological responses in heart rate, percentage of maximal heart rate, oxygen consumption, energy expenditure as compared to bar bending. Perceptual response was also higher in bar fixing as compared to bar bending, but such difference was not statistically significant. oxygen consumption (9.53 vs. 7.14 ml/min/kg, p < 0.05), and energy expenditure (2.67 vs.2.26 Kcal/min, p < 0.05) (186 vs. 158 W, p < 0.05) as compared to bar bending. Perceptual response was higher in bar fixing but such difference was not statistically significant.Findings of this study enable the calculation of daily energy expenditure of rebar work.

Accidents of Electrical and Mechanical Works for Public Sector Projects in Hong Kong

“…The high temperature and humidity environment with low wind speed is insufferable and unfavorable to safety and health of construction workers [ 34 ]. It is believed that prolonged work in a hot environment may result in fatigue, heat-related illness and a higher chance of injury [ 35 , 36 ]. It seems that hot and humid weather in summer is a key contributing factor for E&M works-related accidents.…”

Practical on-site measurement of heat strain with the use of a perceptual strain index

“…For example, a large number of environmental indicators have been developed and been adopted to formulate the "early warning" for working in hot weather (Miller and Bates 2007;Yi and Chan 2014;Zhao et al 2009). Aside from the environmental indicators, the physical indicators, which indicate the physical stress of workers performing physical activities (Kjellstrom and Crowe 2011;Miller and Bates 2007), have been used to evaluate the physical workload of construction workers (Chan et al 2012a;Wong et al 2014;Maiti 2008;Rowlinson and Jia 2014). However, the reliability and validity of these environmental/physical indicators are still debatable regarding different microenvironmental conditions and validation methods (Miller and Bates 2007;Yi and Chan 2014;Hartmann and Fleischer 2005).…”

Perceptual strain index for heat strain assessment in an experimental study: An application to construction workers

“…Upon completion of the above preparation, participants entered into the climatically controlled chamber (Walk-in Chamber, Tai Wan), which maintained ambient conditions of 34.5°C and 75% relative humidity for the experiments to simulate a stressful environment on construction sites (e.g., Wong et al, 2014). Climactic chamber experiments included 30 min of pre-exercise rest, a period of intermittent exercise on the treadmill and 30 min of passive recovery.…”