During a volcanic eruption

During a volcanic eruption:

  • Listen to the radio for civil defence advice and follow instructions
  • If outside at the time of eruption, seek shelter in a car or a building. If caught in volcanic ashfalls, wear a dust mask or use a handkerchief or cloth over your nose and mouth
  • Stay indoors as volcanic ash is a health hazard, especially if you have respiratory difficulties such as asthma or bronchitis
  • When indoors, close all windows and doors to limit the entry of volcanic ash. Place damp towels at thresholds
  • Seal off any air intakes and if you have air conditioning, shut it down
  • Protect your electronics from volcanic ash damage. (Volcanic ash is abrasive and mildly corrosive, and it can damage your computer and electronic systems)
  • Do not tie up phone lines with non-emergency calls
  • If you have to go outside, use protective gear such as masks and goggles and keep as much of your skin covered as possible. Wear eyeglasses, not contact lenses as these can cause corneal abrasions
  • Disconnect drainpipes/downspouts from gutters to stop drains clogging. If you use a rainwater collection system for your water supply, disconnect the tank
  • Stay out of designated restricted zones.

The International Volcanic Health Hazard Network (IVHHN), the US Cities and Volcanoes Commission, New Zealand's GNS Science and the US Geological Survey have prepared guidelines for those who experience volcanic ashfall. The guidelines include procedures to follow if warning of a volcanic ashfall is given, recommendations about what to do during ashfall, and what methods are most effective for cleaning up volcanic ash after the event.


The most effective respiratory protection for adults is to wear a well-fitting, industry-certified facemask such as a N95 mask (also called P2, FFP2 or DS2 in different parts of the world). The certification will be printed on the mask. Such masks are usually disposable.

  • These are highly efficient at filtering ash and are usually designed to fit adult faces well, but may be too big for children.
  • Due to their tight fit, they may feel uncomfortable.
  • Using highly effective masks can make breathing harder; if you have existing respiratory or cardiovascular disease, talk to a health professional about whether such masks are suitable for you.
  • These masks come in many different shapes and sizes. Some fold out into a mask shape and some have a ready-made cup-shape. Some have a valve on the front to improve comfort by letting warm, humid air out. If fitted well to the face, all of these masks will be highly effective at filtering ash.

Some non-certified facemasks state that they are designed to filter ‘PM2.5’ (small particles less than 2.5 micrometres in diameter), which is likely to be the most harmful fraction of the ash.

  • These are probably highly efficient at filtering ash but are often not designed to fit well to the face and so may not be very effective

For more information on what types of mask protect against ashfall click here(external link)