How to safely clean toxic wildfire ash
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Los Angeles residents dealing with wildfire aftermath have yet another obstacle in front of them: toxic ash.
Why it matters: The danger of breathing ash could "top anything that you were breathing in the moment when the fires were burning," says Michael Kleeman, a professor of civil and environmental engineering at UC Davis who's studied air quality in California for more than 30 years.
The big picture: Burned material from the wildfires contains carcinogens. So limit your exposure to ash, and don't let children and other sensitive groups anywhere near the stuff.
The latest: The South Coast Air Quality Management District (AQMD) issued a windblown dust and ash advisory for LA and surrounding areas this week, because high winds may disperse ash south and west from wildfire areas.
How to clean ash in your home, according to experts …
Don't use a leaf blower.
- Sending the ash airborne — via banned leaf blowers or dry sweeping — is extremely dangerous.
- "Ash is toxic, and if you breathe it or get it on your skin, you're definitely taking a cancer risk," Kleeman says.
Cover up.
- Close windows and doors.
- If you're outside, wear gloves, long sleeves, P100 or N95 respirators, socks and shoes, and safety goggles.
- Between the lines: Look for the words "NIOSH" and "N95" printed on the mask. Cloth masks won't cut it.
Wipe surfaces with soap and water
- Use a damp cloth or wet mop on all dusty areas, not limited to the floors.
- Bag dirty cloths and put them in an outdoor trash bin.
- Also: Wash off your pets.
Use air purifiers.
- Top priority: Use HEPA filters.
- Second priority: Use a filter with activated charcoal or carbon.
- Beyond the above, when it comes to fancy air purifier technology, "extra bells and whistles generally are not needed," says Scott Epstein, South Coast AQMD's director of quality and research.
If you have an HVAC system, use a high-efficiency filter that's rated as MERV13, FPR12 or higher, Epstein says.
- There are also EPA-approved DIY air cleaners.
Use AC that recirculates air.
- But avoid the kind that brings outside air in.
- And only consider vacuuming if you have a device with a HEPA filter.
Yes, but: If an entire structure burned, you need a pro to come in.
Go deeper: What the air quality index misses
