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Volcanic Eruptions

Volcanic eruptions can hurl hot rocks for at least 20 miles. Floods, airborne ash, or noxious fumes can spread 100 miles or more. If you live near a known volcano, active or dormant, be ready to evacuate at a moment’s notice. Learn about your community warning systems.

Be prepared for these disasters that can be spawned by volcanoes.

  •  Earthquakes
  •  Flash floods
  •  Landslides and mudflows
  •  Thunderstorms
  •  Tsunamis

During a Volcanic Eruption

Avoid areas downwind of the volcano.

lf indoors:

  • Close all windows, doors, and dampers.
  • Put all machinery inside a garage or barn.
  • Bring animals and livestock into closed shelters.

lf outdoors:

  • Seek shelter indoors.
  • If caught in a rock fall, roll into a ball to protect the head.
  • Avoid low-lying areas where poisonous gases can collect and flash floods can be most dangerous.
  • If caught near a stream, beware of mudflows.

Protect yourself:

  • Wear long sleeved shirts and pants.
  • Use goggles to protect eyes.
  • Use a dust-mask or hold a damp cloth over the face to help breathing.
  • Keep car or truck engines off.
  • Stay out of the area. A lateral blast of a volcano can travel many miles from the mountain. Trying to watch an erupting volcano is a deadly idea.

Mudflows

Mudflows are powerful “rivers” of mud that can move faster than people can walk or run. Mudflows occur when rain falls through ash-carrying clouds or when rivers are dammed during an eruption. They are most dangerous close to stream channels. When you approach a bridge, first look upstream. If a mudflow ls approaching or moving beneath the bridge, do not cross the bridge. The power of the mudflow can destroy a bridge very quickly.

(See more about Mudflows in the Landslides & Mudflows section.)

  

After an Eruption

  •  Listen to a battery-powered radio or television for the latest emergency information.
  •  Stay away from volcanic ashfall.

When outside:

  •  Cover your mouth and nose. A number of victims of the Mount St. Helens volcano died from inhaling ash.
  •  Wear goggles to protect your eyes.
  •  Keep skin covered to avoid irritation or burns.
  •  If you have a respiratory ailment, avoid contact with any amount of ash. Stay indoors until local health officials advise it is safe to go outside.
  •  Avoid driving in heavy ashfall. Driving will stir up more ash that can clog engines and stall vehicles.
  • Clear roofs of ashfall. Ashfall is very heavy and can cause buildings to collapse.