The first morning after the wildfires started appearing a week ago, I could smell the smoke from my front porch, and there was a reddish ash collecting in the corners of the stairs. This is fire ash and it can be composed of partially combusted every damn thing in a house or other structure. So walking your dog, playing in the park, and perhaps even breathing becomes risky to your health. Buzz Kill?
State Advice: Safe Cleanup of Fire Ash
The recent fires have deposited large amounts of ash on indoor and outdoor surfaces in areas near the
fire. Questions have been raised about possible dangers from contact with the ash and safe disposal
procedures. The ash deposited by forest fires is relatively nontoxic and similar to ash that might be
found in your fireplace. However, any ash will contain small amounts of cancer-causing chemicals.
In addition, fire ash may be irritating to the skin, especially to those with sensitive skin. If the ash is
breathed, it can be irritating to the nose and throat and may cause coughing. Exposure to ash in air
might trigger asthmatic attacks in people who already have asthma. Therefore, in order to avoid
possible health problems the following is recommended.
• Do not allow children to play in the ash.
• Wash ash off children’s toys before children play with them.
• Clean ash off house pets.
• Wear gloves, long sleeved shirts, and long pants and avoid skin contact.
• If you do get ash 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
• Avoid getting ash into the air as much as possible. Do not use leaf blowers or take other
actions that will put ash into the air.
• Shop vacuums and other common vacuum cleaners do not filter out small particles, but rather
blow such particles out the exhaust into the air where they can be breathed. The use of shop
vacuums and other non-HEPA filter vacuums is not recommended. HEPA filter vacuums
could be used, if available.
• Well fitting dust masks may provide some protection during cleanup. A mask rated N-95 or
P-100 will be 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
• Persons with heart or lung disease should consult their physician before using a mask during
• Gentle sweeping of indoor and outdoor hard surfaces followed by wet mopping is the best
procedure in most cases. A damp cloth or wet mop may be all that is needed on lightly
• The Regional Water Control Quality Board has asked the public to avoid washing ash into
storm drains whenever possible.
• If ash is wet down, 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 that will prevent it from being disturbed.
Ash and debris inside burned structures may contain more toxic substances than forest fire ash
because of the many synthetic and other materials present in buildings. Older buildings in particular
may contain asbestos and lead. A more cautious approach should be taken in the removal of ash and
other debris from inside burned structures. A NIOSH Interim fact sheet addressing burned structure
clean up safety is attached.