---
title: "What Is Heat Stroke? Heat Stress and Hydration Glossary"
description: "Heat stroke is the most serious heat-related illness. The body can no longer control its temperature, and the worker needs emergency care. Call 911."
url: https://jmarsolutions.multisites.ai/glossary/heat-stroke
publisher: JMAR Solutions
phone: +1-214-632-7780
quote: https://jmarsolutions.multisites.ai/contact
---

Heat illness

# Heat stroke

Heat stroke is the most serious heat-related illness. The body can no longer control its temperature, and the worker needs emergency care. Call 911.

Heat stroke is a medical emergency. The body can no longer control its temperature, sweating can fail, and body temperature can rise to 106°F or higher within 10 to 15 minutes. Without emergency care it can cause permanent disability or death.

Watch for confusion, slurred speech, seizures, or loss of consciousness. Call 911 right away. Stay with the worker, move them to a cool, shaded area, and cool them fast with cold water, wet skin or cold wet cloths. Do not treat it with drinks or a supplement. It differs from [heat exhaustion](https://jmarsolutions.multisites.ai/glossary/heat-exhaustion). Compare the two in our [guide](https://jmarsolutions.multisites.ai/guides/heat-exhaustion-vs-heat-stroke) and learn how to prevent it in the [heat illness pillar](https://jmarsolutions.multisites.ai/heat-illness).

[From JMAR SolutionsHydration programs and toolbox talks for crews](https://jmarsolutions.multisites.ai/hydration-programs)

## Related terms

-   [Heat exhaustion](https://jmarsolutions.multisites.ai/glossary/heat-exhaustion)
-   [Heat stress](https://jmarsolutions.multisites.ai/glossary/heat-stress)
-   [Core body temperature](https://jmarsolutions.multisites.ai/glossary/core-body-temperature)
-   [Buddy system](https://jmarsolutions.multisites.ai/glossary/buddy-system)

## Sources

1.  [CDC NIOSH: Heat-related Illnesses](https://www.cdc.gov/niosh/heat-stress/about/illnesses.html)
2.  [CDC NIOSH: Heat-related Illnesses](https://www.cdc.gov/niosh/heat-stress/about/illnesses.html)

![Ironworkers silhouetted on a steel frame against a hot orange sunset](https://jmarsolutions.multisites.ai/_astro/sunset-steel.IhAMDca0_6wk53.webp)

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