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URL of this page: https://medlineplus.gov/volcanoes.html

Volcanoes

Summary

A volcano is a vent in the Earth's crust. Hot rock, steam, poisonous gases, and ash reach the Earth's surface when a volcano erupts. An eruption can also cause earthquakes, mudflows and flash floods, rock falls and landslides, acid rain, fires, and even tsunamis.

Volcanic gas and ash can damage the lungs of small infants, older adults, and people with severe respiratory illnesses. Volcanic ash can affect people hundreds of miles away from the eruption.

Although there are no guarantees of safety during a volcanic eruption, you can take actions to protect yourself. You should have a disaster plan. Being prepared can help reduce fear, anxiety, and losses. If you do experience a disaster, it is normal to feel stressed. You may need help in finding ways to cope.

Federal Emergency Management Agency

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The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.