Articles

Fine particles, formaldehyde and other air contaminants are created when common cleaning agents are exposed to indoor ozone. When used indoors in the presence of ozone, many household cleaners and air fresheners emit toxic pollutants at levels that may lead to health risks according to a new study by researchers at the University of California, … More

Another study confirms that ionizers and ozone generators can create unhealthy levels of ozone in poorly ventilated rooms. The news does not appear to be getting any better for ionizers, ozone generators or other devices that generate ozone and claim to be “air purifiers.” Another study has raised additional concerns about these devices. This study … More

Air cleaners and air filters alone have not been shown to be clinically effective at reducing allergy symptoms. Last Friday (March 31) I was very fortunate to be able to participate in a round table discussion on indoor air research. This meeting was conducted by university indoor air scientists and engineers and was attended by … More

Some new air cleaning devices are using free radicals or Reactive Oxygen Species (ROS) to “oxidize” indoor air. Free radicals have been shown to be damaging to human health. Testing is lacking on the by-products of the reactions between free radicals and the components of indoor air. Here is a quote from a brochure on … More

Be wary of excessive marketing claims for products to take care of indoor air. For hundreds of years wizards and alchemists sought a way to be able to create gold from lead and/or other metals. From time to time one or more of them claimed that they found the way. In many cases this involved … More

Inner City Asthma Study shows effectiveness of comprehensive environmental controls including air purifiers to control asthma. In the last week a number of articles have appeared in newspapers, magazines and TV with the headline: “Air Cleaners: Even the most effective Could be a Questionable Investment.” These articles are based on the Consumer Reports study of … More

Gaps between filters can cause significant decreases in filter efficiency. Proper filter installation is a key ingredient in ensuring filter effectiveness. Gaps between filters can create pathways for entry of major quantities of particles. Dr. Jeffrey Siegel of the University of Texas at Austin has found that a 10-millimeter gap between filters can substantially drop … More