Research findings to action: prevention of heat stress in hot climates

Introduction
The United Arab Emirates (UAE), in common with other Middle Eastern countries with desert environments, experiences daytime temperatures that often exceed 45 degrees C (135 degrees F), especially in July and August. Workers in outdoor workplaces, such as in the construction and oil industry, are exposed to the risk of health effects from exposure to environmental heat compounded by shift work without adequate rest breaks, and socio-cultural practices. There is an identified need to understand and develop guidance to reduce heat stress in these work environments.

Methods
The Health Authority Abu Dhabi in the UAE commissioned a project to produce scientifically validated guidelines and protocols to prevent heat-related illness and manage heat stress. 207 workers from 5 sites were recruited for a longitudinal study that involved the measurement of core body temperature, heart rate, and urine specific gravity. Environmental thermal stress indices - TWL (Thermal Work limit) and WBGT (Wet Bulb Globe Temperature) were determined.

Results
During work shifts where the dry bulb temperatures often exceeded 45 degrees C, with globe temperatures up to 10 degrees higher, and high relative humidity, core body temperature was not elevated, and there was no indication of fatigue. This was despite WBGT calculations showing considerable thermal stress. TWL calculations however correctly predicted that well hydrated workers could perform unpaced work in hot conditions without a significantly increased risk of heat stress. 
As a result of the research, health promotion material was produced by the Health authority, and this was launched with sufficient publicity. 465 companies employing 815,000 workers distributed material across 4,460 worksites. Two large participating companies indicated subsequent decreases in the incidence of heat related cases. 

Discussion
This project demonstrates that research findings on heat stress when translated into practical advice on prevention and management can result in a decrease in heat-related illness.