Research

Hydration status and physiological workload of UAE construction workers: A prospective longitudinal observational study

Graham P Bates^{* 1} and John Schneider^{* 2}

¹School Public Health, Curtin University, Perth, Australia

²Department of Community Medicine, Faculty Medicine and Health Sciences, UAE University, Al Ain, United Arab Emirates

author email corresponding author email* Contributed equally

Journal of Occupational Medicine and Toxicology 2008, 3:21doi:10.1186/1745-6673-3-21

Published:	18 September 2008

Abstract

Background

The objective of the study was to investigate the physiological responses of construction workers labouring in thermally stressful environments in the UAE using Thermal Work Limit (TWL) as a method of environmental risk assessment.

Methods

The study was undertaken in May 2006. Aural temperature, fluid intake, and urine specific gravity were recorded and continuous heart rate monitoring was used to assess fatigue. Subjects were monitored over 3 consecutive shifts. TWL and WBGT were used to assess the thermal stress.

Results

Most subjects commenced work euhydrated and maintained this status over a 12-hour shift. The average fluid intake was 5.44 L. There were no changes in core temperature or average heart rate between day 1 and day 3, nor between shift start and finish, despite substantial changes in thermal stress. The results obtained indicated that the workers were not physiologically challenged despite fluctuating harsh environmental conditions. Core body temperatures were not elevated suggesting satisfactory thermoregulation.

Conclusion

The data demonstrate that people can work, without adverse physiological effects, in hot conditions if they are provided with the appropriate fluids and are allowed to self-pace. The findings suggested that workers will self-pace according to the conditions. The data also demonstrated that the use of WBGT (a widely used risk assessment tool) as a thermal index is inappropriate for use in Gulf conditions, however TWL was found to be a valuable tool in assessing thermal stress.