Safe Cleanup of Wildfire Ash

Safe Cleanup of Wildfire Ash

Safe Cleanup of Wildfire Ash

Ash from wildfire is deposited on indoor and outdoor surfaces and contains cancer-causing chemicals.

Wildfire Ash

Ash has been deposited on indoor and outdoor surfaces in areas near the recent wildfire. Ash from forest fires is relatively nontoxic and is similar to ash that might be found in your fireplace; however, all ash contains small amounts of cancer-causing chemicals.

Fire ash may also irritate the skin, especially to those with sensitive skin. If ash is inhaled, it can be irritating to the nose and throat and may cause coughing. Exposure to ash in the air can also trigger asthmatic attacks.

To avoid possible health issues:

  • Do not allow children to play in the burn debris or ash areas.
  • Wash ash from toys before allowing children to play with them.
  • Wash ash off of household pets.
  • Wear gloves, long-sleeved shirts, and long pants when cleaning ash, and avoid skin contact. If ash does get on your skin, wash it off as soon as possible.
  • If you have a vegetable garden or fruit trees, wash the fruit or vegetables thoroughly before eating them.
  • Do not consume any food, beverages, or medication that has been exposed to burn debris or ash.
  • Clean all utensils, glasses, and dishware before use by:
    • Washing them in a strong detergent solution and then soaking them in a bleach solution of one teaspoon of bleach per quart of water for 15 minutes, or
    • Using the long dishwasher wash cycle as long as the dishwasher is debris free, heats water to at least 140 ̊F, and has a heated drying cycle.
  • Avoid circulating ash into the air as much as possible. Do not use shop vacuums and other non-HEPA filter vacuums, as they do not filter out small particles and can blow particles into the air where they can be breathed in. HEPA filter vacuums can be used, if available.
  • Well-fitting dust masks may provide some protection during cleanup. Masks rated N-95 or P-100 are more effective than simpler dust or surgical masks in blocking particles from ash. In general, many ash particles are larger than those found in smoke; thus, wearing a dust mask can significantly reduce (but not completely eliminate) the amount of particles that are inhaled.
  • Persons with heart or lung disease should consult with their physicians before using a mask during post-fire cleanup.
  • In most cases, gently sweeping indoor and outdoor hard surfaces followed by wet mopping is the best way to clean up ash residue. A damp cloth or wet mop may be all that is needed on lightly dusted areas.
  • Avoid washing ash into storm drains whenever possible.
  • If you wet down ash, use as little water as possible.
  • Collected ash may be disposed of in the regular trash. Ash may be stored in plastic bags or other containers to help prevent it from being disturbed.
  • Ash and debris inside burned structures may contain toxic substances other than forest fire ash because of synthetic and other materials present in buildings. Older buildings, in particular, may contain asbestos and lead. A more cautious approach should be taken when removing ash and other debris from inside burned structures.

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Environmental Health Division

Main: 303-441-1564
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