A volcano is a mountain or hill with an opening or vent from which gaseous liquid or solid materials from the earth's interior are ejected. The term is also used for mountains, hills, or craters formed by the accumulation or removal of materials during past volcanic events even if no active vent is presently existing.

A volcanic eruption is the process wherein volcanic materials such as lava, fragmented rocks or gases are emitted or ejected through a crater, vent or fissure on to the earth's surface to form new deposits.

Links to Safety and Preparedness Information on Volcanic Hazards: ASH and GASES.

Sourced from the International Volcanic Health Hazard Network (IVHHN): https://www.ivhhn.org/home.

Preparedness for Ash Fall:



Health Impacts of Volcanic Ash:



Protection from Breathing Ash:





Health hazards of volcanic gases:







Expected Hazards form Volcanic Eruption

  • Blasted Projectiles: Large projectiles can damage buildings; if these are hot they can start fires.
  • Mud Flows (lahars): Frequently accompany volcanic eruptions and can be lethal. Lakes can mix with volcanic rock and debris to form a near-solid flow which engulfs all in its path.
  • Pyroclastic Flows: Mixtures of hot gases, ash, fine pumice and rocks; danger lies in the density and temperature of the ash and rock fragments. Pyroclastic flows can move at very high speeds, possibly over 100 km/h. Hazards include body surface burns, inhalation injuries and asphyxia.
  • Gasees: These may be asphyxiants which are concentrated near the volcanic crater or fissure or respiratory irritants which are more dispersed and can be harmful at lower concentrations.
  • Lava Flows: These are flows of extremely hot molten rocks extruded by the volcano. The viscosity and high temperature make these flows very dangerous and they are capable of destroying all in their path.
  • Local Earthquakes: Possible loss of human life and property.
  • Tsunamis: Tsunami is Japanese for "tidal wave", the seismic wave that can hurtle across oceans at up to 600 miles per hour (800 km/hour). Occurrence is unpredictable and can destroy coastlines.

Before the Eruption

  • Listen and obey official instructions and advisories
  • Participate fully in the planning, preparedness, hazard mapping, evacuation planning and search and rescue activities and processes if you live in a volcano prone area
  • Take a proactive attitude and stance to volcano preparedness, planning and mitigation
  • Have a well prepared evacuation plan

During the Eruption

  • Listen and obey official instructions and advisories
  • Evacuate to safe zone as established by relevant authority and or as instructed
  • Follow evacuation orders from local authorities. Evacuate early.
  • Avoid areas downwind, and river valleys downstream, of the volcano. Rubble and ash will be carried by wind and gravity.
  • Take temporary shelter from volcanic ash where you are if you have enough supplies. Cover ventilation openings and seal doors and windows.
  • If outside, protect yourself from falling ash that can irritate skin and injure breathing passages, eyes, and open wounds. Use a well-fitting, certified face mask such as an N95.
  • Avoid driving in heavy ash fall.
  • Report to collection site and await further instructions
  • Seek safer ground immediately and well away from the effects and events of the volcano
  • Do not enter or attempt to enter danger zone as established by the relevant authorities
  • Cooperate with authorities and relevant personnel

After the Eruption

  • Listen and obey official instructions and advisories
  • Do not enter or attempt to enter into declared danger zones as established by the relevant authority
  • Stay clear from collateral activity and await further instructions
  • Assist where possible in information sharing and eye witness accounts for purposes of search and rescue and recovery

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