Heat Illness Prevention

sweating in the heatWhat is heat illness?

Heat illness is a medical condition resulting from the body’s inability to cope with a particular heat load and includes, but is not limited to, heat cramps, heat rash, heat exhaustion, fainting, and heatstroke. Prolonged or intense exposure to hot conditions and heavy physical work even in cooler conditions can lead to your body overheating. Symptoms of heat illness may not be recognized initially and can quickly progress.

Why is it important to know about heat illness?

Heat illness is preventable but, if left unchecked, could lead to death. People who work outside, especially in the summer, are exposed to heat and can get heat illness. Heat illness can also lead to injuries. Workers are more likely to get injured if they get tired or dizzy from the heat while working. Heat exposure can also lead to heatstroke, a condition that can be fatal. What you learn here will prepare you for helping your co-workers and yourself stay safe when working in hot weather.

Workplace Tools


Symptoms and treatment for heat illness

Know the symptoms and treatment to prevent serious heat stress and death.

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Best Practices for Heat Illness in Agriculture

Reduce heat illness for outdoor agricultural workers. In English and Spanish.

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Heat Illness Facilitator's Guide

A train-the-trainer guide. Part of the Heat Illness Toolkit.

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Heat Education and Awareness Tools (HEAT Toolkit) webpage

Washington State Heat Rule

On June 27, 2023, the Washington State Department of Labor & Industries (L&I) adopted updates to Outdoor Heat Exposure rules to prevent heat-related illness and reduce traumatic injuries associated with heat exposure, effective July 17, 2023. The adopted rule for agriculture (WAC 296-307-097) includes requirements for shade, rest, and acclimatization, and lowers the temperatures at which some preventive actions must be taken. The requirements are year-round, in effect whenever workers are exposed to outdoor heat. Visit the WA Department of Labor and Industries webpage to learn more about these requirements. 

Oregon State Heat Rule

Oregon adopted two permanent rules in 2022 to protect workers from heat-related illnesses. Rule OAR 437-004-1131 applies to agricultural workplaces. Overall, the adopted requirements address access to shade; drinking water; high heat practices, including the development of heat illness prevention break schedules for certain temperature thresholds; emergency medical and actions plans; acclimatization plan; heat illness prevention plan; supervisor and employee training; and training documentation. Visit the OR Occupational Safety and Health Administration webpage to learn more about these requirements.

Regional and National Resources

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Heat Stress

PNASH Resources


Online Learning: Heat-Related Illness Prevention

An online course with practical resources, ready-to-use toolkits. Developed by researchers and agricultural partners.


Best Practices for Heat Illness in Agriculture

Tips and strategies to reduce heat illness for outdoor agricultural workers. In English and Spanish.

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#BeHeatSmart Media Toolkit

This social media kit was developed to promote heat safety preparedness in the agricultural industry. In pdf format and updated for 2023.

PNASH Research

A Multi-Level Approach to Heat-Related Illness Prevention for Agricultural Workers

NIOSH Funding Period 2016-2022 | June Spector, MD, MPH

This project proposes to develop and evaluate a multi-level approach to heat-related illness (HRI) prevention in agricultural workers. The intervention will develop tools to prevent the negative health effects of prolonged heat for individuals (knowledge and behaviors), workplaces (policies and practices), and communities (homes).

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CLEAN AIR–I CARE: Stressors of Balancing Childcare, Work, and Concerns of Wildfire Smoke Exposures for Farmworker Parents

PNASH Pilot Project 2021-22 | Savannah D’Evelyn, PhD

Working outside amid heat and wildfire smoke makes summer farm work grueling. But for those who are also parents, these challenges are compounded by the pressure of balancing work and childcare, and concerns about their children’s health in the smoke. Farmworkers also have few wildfire and smoke information sources that are non-written or in Spanish. 

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Heat Exposure, Injury Risk, and Productivity in Agricultural Workers

NIOSH Funding Period 2014-2017 | June Spector, MD, MPH

This project examines the association between heat exposure and traumatic injury risk in agricultural workers, the relationship between heat stress and productivity, and the feasibility of using a biomarker of heat acclimation to detect workers at risk for heat-related illness and injury, with the ultimate goal of prevention. 

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