Air Cleaner Information for Consumers
Not all air-cleaning devices are appropriate for home use; some are known to be harmful to human and animal health. Ozone generators, which are portable or in-duct air cleaners that intentionally create ozone, can produce levels that are much higher than health-based standards. There are companies that try to sell the idea that breathing ozone is actually healthy, but there are 40 years of scientific studies that show even relatively low concentrations of ozone are harmful to biological tissue in plants and animals, including humans. It is well-documented that ozone can cause respiratory tract irritation and inflammation, serious breathing difficulty including asthma, permanent lung damage, and cardiovascular effects. The American Lung Association has concluded that breathing even low levels of ozone increases the risk of premature death.
There are industrial uses of ozone at high concentrations because it can kill biological pathogens and neutralize odors. Ozone used for these purposes is typically applied under controlled conditions to prevent human exposures. CARB strongly advises against the use of ozone generators at home because of the risk to you and your family's health from exposure to ozone.
California Certified Air Cleaners
In 2008, CARB enacted an air cleaner regulation to limit the ozone emissions from indoor air cleaning devices. The regulation requires all indoor air cleaners sold in California to be certified by CARB, including air cleaners sold online. Approved air cleaners are listed at California Certified Air Cleaning Devices, which is regularly updated. Approved air cleaners must also show a label on the packaging similar to the sample label shown below. Even though fully-integrated in-duct air cleaning devices are currently exempted from the regulation, some in-duct devices may create ozone at unhealthy levels. CARB is amending the air cleaner regulation to include in-duct devices in the future. For more information on the regulation, please read the Frequently Asked Questions.
In addition to CARB certification, there are other factors to consider in selecting a suitable air cleaner. It's important to choose an air cleaner with a Clean Air Delivery Rate (CADR) that matches the size of the space you want to clean. So, check both the certified list and the information in the sections below to make the best choice for your needs.
How to Select a Safe and Effective Air Cleaner
- Air Cleaning Devices for the Home Frequently Asked Questions
- Verification Program for Portable Electric Room Air Cleaners (Clean Air Delivery Rates) - Association of Home Appliance Manufacturers (AHAM)
- Residential Air Cleaner Use to Improve Indoor Air Quality and Health: A Review of the Evidence - National Collaborating Centre for Environmental Health (October 2010)
- U.S. EPA Guide to Air Cleaners in the Home (2018)
Air Cleaners to Avoid
- Hazardous Ozone-Generating "Air Purifiers"
- List of Potentially Hazardous Ozone Generators Sold as Air Purifiers
Other Air Cleaner Information
- Air Cleaner Regulation Information for Manufacturers
- CARB Report: Evaluation of Ozone Emissions From Portable Indoor "Air Cleaners" That Intentionally Generate Ozone (2006)
- CARB Report: Evaluation of Ozone Emissions from Portable Indoor Air Cleaners: Electrostatic Precipitators and Ionizers (2008)
- CARB Research Project: In-duct Air Cleaning Devices: Ozone Emission Rates and Test Methodology (2014)
- CARB Research Project: Formaldehyde Emissions from HVAC Filters (2018)
- CARB Research Project: Benefits of High Efficiency Filtration to Children with Asthma (2018)
Additional Information on Indoor Air Quality
- CARB Research Project: Ventilation and Indoor Air Quality in New Homes (2009)
- Formaldehye in Indoor Air
- CARB Indoor Air Quality Research
- Reduce Your Exposure to Particle Pollution
- Indoor Air Pollution from Cooking
- Asthma and Air Pollution
- CARB Report: Air Quality in Child Care Facilities
- Flooring Made with Composite Wood Products
- U.S. EPA Indoor Air Quality
If you need further assistance after reviewing these links, contact us at (916) 445-0753. If you are interested in upcoming activities related to the regulation, subscribe to the Air Cleaner Regulation Topic or contact us at aircleaners@arb.ca.gov.