CARB certified air cleaners, explained
California's ozone limit for indoor air cleaners.
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What the rule does
CARB says that, under California Assembly Bill 2276, it adopted an air cleaner regulation to limit the amount of ozone produced from indoor air cleaning devices. It says the regulation became final on October 18, 2008. CARB says amendments to the regulation took effect on October 1, 2020.
Which air cleaners it covers
CARB says the regulation requires all indoor air cleaners sold in California to be certified by CARB, including air cleaners sold online. CARB says it is not certifying mechanical in-duct air cleaning devices that use only HEPA filtration.
What certification is based on
CARB says certification "is based on a device's low (usually near-zero) ozone emissions and electrical safety."
The label
CARB says the text required on labels of certified air cleaners should now read: "Meets California ozone emissions limits. CARB certified."
What it does not tell you
CARB says there are other factors to consider besides certification, and that it is important to choose an air cleaner with a CADR that matches the size of the space. Certification is based on ozone emissions and electrical safety. It is not a rating of how well a unit filters or cleans the air.
The two lists
CARB keeps a list of certified air cleaning devices and a separate list of potentially hazardous ozone generators sold as air purifiers. CARB says that if an ozone generator is not on the hazardous list, it does not mean that it is safe for use.
What we do and do not say
We do not say any air cleaner is CARB certified or meets California's limits. To check a device, use CARB's own list. This page is general information, not legal advice. If you make or sell air cleaners, read CARB's regulation.
Sources: California Air Resources Board, Air Cleaner Regulation (AB 2276); California Air Resources Board, Air Cleaner Information for Consumers; California Air Resources Board, Hazardous Ozone-Generating Air Purifiers; EPA, Does EPA certify/register or provide lists of acceptable air cleaners or manufacturers/sellers?.
FAQ
General information only. An air purifier is not a substitute for ventilation, for removing the source of a pollutant, or for medical care. Read and follow the maker's manual. The California Air Resources Board strongly advises against the use of ozone generators in spaces occupied by people or animals. If you have asthma, allergies, or heart or lung disease, talk to your doctor. During wildfire smoke, follow local officials and be ready to evacuate. In an emergency, call 911.
Next: ozone and ionizers
Why ozone is a health risk.
