California air-purifier regulations hit home

Shop for a portable air purifier in California as of today, and you might notice a new label on the package. The state's new regulation (PDF), surpassing those of the federal government and any other state, limits the amount of ozone a portable air purifier offered for sale can generate—even as a by-product. The law covers portable air purifiers sold over the Internet and through catalogs as well as in stores.

Ground-level ozone, the chief ingredient of smog, has been linked to decreases in lung function and increased risks of throat irritation, coughing, chest pain, and lung-tissue inflammation. Filter air purifiers like most in our recent report (Ratings available to subscribers) trap dust, pollen, and smoke without emitting ozone. Electrostatic precipitators typically create ozone in small amounts, although Consumer Reports recommends against introducing anything to your home that emits ozone even in small amounts.
 
The law that takes effect in California today, announced three years ago, affects products used or intended for use in occupied spaces such as homes, businesses, and schools. All such air cleaner models marketed or sold in the state must have been tested and certified to emit no more than 50 parts per billion (ppb) of ozone in order to be sold in the state. That level, in federal law, actually pertains solely to medical devices. While air purifiers don't fit into this classification, California uses Underwriters Laboratories' (UL's) Standard 867 (PDF), which tests to a 50-ppb limit.

Whole-house air purifiers, which replace the filter of a home's forced-air system, are not covered by the ruling. Neither are so-called "industrial-use" products, even ozone generators, sold to and intended for use by professionals in uninhabited spaces.
 
Although portable air purifiers you see in stores need to be tested and certified, manufacturers won't be required to label their products as certified for another year. By October 18, 2011, products must bear a label approved by California's Air Resources Board.
 
—Ed Perratore
 
Cleaner air: Before even considering an air purifier, take some basic steps, including removing carpets, keeping pets out of bedrooms, banning indoor smoking, and opening windows when possible.