Prevention of heat-related illnesses in occupational settings: Emerging strategies for the Asia-Pacific region

Abstract

Heat-related illnesses (HRI) represent a growing occupational health challenge in the Asia-Pacific region, where an estimated 74.7% of workers are exposed to occupational heat stress. Workers in agriculture, construction, manufacturing, and outdoor service industries experience conditions ranging from heat cramps to fatal heat stroke. This narrative review examines current evidence on the epidemiology, physiological mechanisms, and prevention strategies of occupational HRI across Asia-Pacific countries. A systematic literature search was conducted using PubMed, Embase, and CINAHL databases for studies published between 2020 and 2025. Regional surveillance reveals 53 061 reported cases of occupational HRI in China, with an approximately 21% increase in risk for each 1 °C rise in ambient temperature. In India, up to 84% of workers report adverse health outcomes when workplace heat exposure exceeds recommended temperature thresholds. Climate projections indicate continued temperature increases across the region, with economic losses projected to reach approximately USD 2.4 trillion annually by 2030. South Asia alone is expected to lose 5% of working hours, equivalent to 43 million jobs. Evidence-based prevention strategies include the application of Wet Bulb Globe Temperature-based exposure limits (ranging from 25 °C to 31 °C depending on work intensity), structured 7-14 day acclimatization programs, and mandatory work-rest schedules. Policy frameworks vary substantially. While countries such as Singapore and Qatar have established legally binding protections, most informal-sector workers remain unprotected. Chronic health consequences including heat-associated kidney disease affect up to 42% of workers in some agricultural communities. Understanding and implementing effective occupational heat prevention strategies is increasingly critical as climate change continues to threaten worker health, labor productivity, and sustainable economic development in the Asia-Pacific region.

Keywords

Heat-related illness / Occupational health / Heat stress prevention / Asia-Pacific / Workplace safety

Conflict of interest statement

The authors declare that there is no conflict of interest.

Funding

This study received no extramural funding.

Data availability statement

The data supporting the findings of this study are available from the corresponding author upon request.

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