Ozone: What Air Cleaner Advertisers Don’t Tell You
by Frank Hammes
IQAir North America
Santa Fe Springs, Calif.

Every scientific discovery has its watershed moment. In indoor air quality, one of the great watershed moments in the awareness of indoor ozone came in 1983 when a student at the University of Colorado in Boulder wrote a paper for his science class about his summer job. 

He titled it “Ozone Toxicity – How Copier Machines Made Me Sick.” The student had worked in a small windowless room in the university library. His job was to run off copies for the school’s professors. Soon, he developed headaches, a cough, irritated sinuses, and a myriad of other symptoms. Somehow, he got steered in the direction of what was making him sick. The copier machines were creating the lung irritant ozone, the main component of smog.

What no one could have expected was the domino effect that came next. The student took his paper to the local copy shop to have copies printed for his class. The copy shop workers saw the paper and made copies for themselves. Many of them had been experiencing the same problems, but they didn’t know what had caused their symptoms.

Soon, copies of the paper started to circulate to other shops that were part of the same national chain of copier stores. As awareness of the issue grew, the copier machines were fitted with ozone filters, ventilation was added to the shops, and copier maintenance companies began to stress the need to maintain the filters properly. The problem was corrected quietly – very quietly. Today, 21 full years later, it is air cleaners – of all things – that are producing ozone indoors. Last year, an estimated four million air cleaners sold in the United States. Ironically, nearly half of those machines produce ozone.

Ozone-producing air cleaners are being aggressively marketed in the United States. Rarely does a day go by when I do not receive a direct mail advertisement or hear a radio or television campaign for these products. They are being distributed by some of the most well-known and popular retailers
of upscale products in the country. Due to the advertising dollars these retailers command, they have even enlisted the nation’s leading radio personalities to hawk their wares, including popular stars who personally endorse the ozone-producing products.

The spin that these radio spots and infomercials put on ozone generating air cleaners would be laughable if it weren’t so frightening: “Smell that sweet fresh ozone in your home.” “One unit is good for a whole house.” “It’s nature’s way of freshening the air.” “These machines are used by the Pentagon.” Astonishingly, one ozone-producing air cleaner has even been able to convince a national allergy and asthma support organization into putting its seal of approval onto all of their advertising. A recent trend has been to drop the word “ozone” out of the ads for these machines completely.

This may be because the American Lung Association, the U.S. Environmental Protection Agency and Food and Drug Administration, Health Canada, and just about every other respected health organization advises against using ozone-generating air cleaners. The company using the seal of approval stresses that it is an electrostatic air cleaner – not an ozone generator – and that it produces only small amounts of ozone as a byproduct.

Truth be told, I’m not able to comprehend any difference between ozone that is created by an ozone generator and ozone produced by an electrostatic air cleaner. The legal limit for both machines in occupied spaces is the same. Ozone is ozone. The whole situation makes me feel like Howard Beale, Peter Finch’s character in the movie “Network.” Beale, a longtime television journalist and prestigious anchor of the evening news, makes an on-the-air plea urging viewers to “go to the window, open it, stick your head out and yell, ‘I’m mad as hell and I’m not going to take this anymore.’”

Ozone is a lung irritant. Ozone is an asthma trigger. And yet these machines are being heavily advertised to parents of children who could die from an asthma attack. The manufacturers of these machines have worked hard to create a new concept: safe levels of ozone. 

Well, guess what? Research has shown that there is no safe level of ozone that can be added to the air. “Current evidence of the health effects of ozone suggests that there is no safe threshold concentration for the onset of health responses due to exposure above background ozone concentrations,” H. Sterling Burnett wrote in 1994. 

In the United States, 50 parts per billion is the designated acceptable limit for ozone production in the home. A recent University of Southern California study demonstrated that an increase of ozone by only 20 ppb increased school absences by 83 percent. I’m interested to find out if anyone can demonstrate how 50 ppb is the safe level for indoor ozone exposure. It reminds me of the health recommendation that you shouldn’t “smoke more than two packs of cigarettes a day.” That was the health advice that was being commonly quoted just before the surgeon general’s report on tobacco was issued in 1964.

Prior to that, there was considered to be a safe or even healthful level of smoking. Who thought it was safe and healthful to smoke? Well, primarily the advertisers who were trying to sell you cigarettes – that’s who. It is the same situation today. The advertisers who are selling ozone producing air cleaners are spending millions and millions of dollars to convince you that ozone is safe and healthy in your home. They are dead wrong.

We know that asthma is increasing at an alarming rate. Asthma is at its worst in areas that have increased rates of asthma triggers. Ozone is a clearly established asthma trigger. There are daily ozone health watches on the news that warn parents of children with asthma that they should stay indoors on some days; these health watches look at the ozone levels outside. How can someone tell parents in good conscience that the asthma trigger they are putting in their children’s bedroom is at a safe level? How has “safe” been established here? Is there a safe number of cigarettes you can have each day? Is there a safe level of secondhand smoke for you or your kids?

The Internet is the soapbox for the angry person with something to say. If you go to the allergy and asthma support Web sites, you are going to find a lot of angry men and women. Mothers and fathers of children with asthma are posting their experiences with ozone generating air cleaners on the support sites.

On one site for parents of children with asthma, a mother is encouraged by another woman to try one of the ozone-generating air cleaners that are popularly sold on infomercials. The mother responds, “Actually, we tried a [sic] air cleaner that did emit ozone and [daughter] Anaya flared so badly she ended up in the hospital.” Another mother tells of getting ionizing air cleaners to help her three daughters with their asthma. All of the girls ended up getting headaches and their asthma situation worsened.
A student reporter at Massachusetts Institute of Technology ended up having to go to urgent care after he took the assignment of reviewing an ozone producing air cleaner for the school paper. Hopefully, awareness of the dangers of ozone producing air cleaners will grow, and changes will come. At press time, I am aware of four class-action lawsuits that have been filed recently against the manufacturers, distributors and retailers of ozone-producing air cleaners. It’s happening. People have gone to the window. They’ve opened it. They are sticking their heads out and shouting that they are mad as hell, and they aren’t going to take it any more.

Frank Hammes is the director of research and development at The IQAir Group in Switzerland and president of IQAir North America in Santa Fe Springs, Calif. IQAir North America has partnered with the American Lung Association to educate the public on the importance of indoor air quality. Hammes has been involved in the development of affordable customized air cleaning solutions for residential, medical and commercial applications for nearly 20 years. After graduating with a master’s degree in law from Trinity College, Cambridge University, England, he joined the then-35-year-old, family-owned air filtration business. He has been responsible for the development of air cleaning systems for automobiles, residential and medical applications. Hammes currently holds several patents relating to improving the design and performance of air cleaning systems.Living in Switzerland and California Hammes has a unique insight into the IAQ issues both in Europe and the United States. He is a regular contributor to indoor air conferences and publications in Europe, the United States and Asia. He is the course leader for IQAir Air Cleaner College. He can be reached by e-mail at  or by phone at (562) 903-7600 The opinions expressed in this article are the opinions of Mr. Hammes and are not the opinions of this publication or the publication’s staff. Persons holding opposing views are invited to submit articles to IE Connections for publication.

 Ozone Generators and IAQ 
         With the considerable recent media attention focused on the issues of indoor air quality, 
         microbial contaminants in particular, ozone is once again being touted as a remedy for all 
         manner of indoor air quality concerns. Marketing literature from distributors of ozone 
         generators boast claims of eliminating microbial contaminants through the use of ozone. One 
         website claims "Ozone helps kill mold and mold odors with large ozone dose shock treatments" 
         and "Ozone may be the only way to save your home from deadly mold". The propaganda goes 
         as far as claiming that ozone destroys mold leaving only oxygen, hydrogen and carbon 
         dioxide. These are the kind of unsubstantiated claims that led to a $1.49 million civil penalty 
         against Alpine Industries in April of 2001 and a Court Order to cease making health claims for 
         its ozone generators. A recent study has demonstrated that gas phase ozone is ineffective in 
         reducing the viability of Penicillium spores on building materials at levels as high as 9 parts per 
         million (ppm), levels that are much higher than those attainable under field conditions 
         (Appl.Occup.Environ.Hyg. 12(8), August 1997). Recent studies have also implicated a 
         synergistic effect between fungal spores and ozone and increased symptoms of asthma in 
         asthma patients using an inhaler on an as-needed basis (Am.J.Respir.Crit.Care.Med. 154(3 Pt 
         1):633-41, Sept. 1996). 

         The U.S. Occupational Safety and Health Administration (OSHA) limits ozone exposure in 
         industrial settings to 0.1 ppm over an eight hour day, six days per week. The Food and Drug 
         Administration has set a limit of 0.05 ppm for the ozone generated from electronic air cleaners 
         used as medical devices. The Environmental Protection Agency has stated: 

         Available evidence shows that, at concentrations that do not exceed public health standards, 
         ozone is generally ineffective in controlling indoor air pollution. The concentration of ozone 
         would have to greatly exceed health standards to be effective in removing most indoor air 

         To read the entire EPA article please visit "Ozone Generators that are Sold as Air Cleaners" 

         Microbial Fact #1: 
         Campylobacteriosis is an infectious disease caused by bacteria of the genus Campylobacter. 
         Most people who become ill with campylobacteriosis get diarrhea, cramping, abdominal pain, 
         and fever within 2 to 5 days after exposure to the organism. (From the CDC website) 

         Fungal Fact #1: 
         Cryptococcus neoformans var. neoformans has been isolated from the soil worldwide, usually 
         in association with bird droppings. A less common etiologic agent, C. neoformans var. gattii 
         has been isolated from eucalyptus trees in tropical and sub-tropical regions. (From the CDC 

         We would like to acknowledge the contributions of our employees to the relief efforts 
         following the attacks of September 11, 2001. To date, with Aerotech's matching 
         contribution, our employees have donated over $10,000.00 to the American Red Cross 
         Disaster Relief Fund. Aerotech Laboratories and its subsidiaries Precision Analytical and 
         Kalmar will also donate 1% of all cash receipts received during the month of October 2001 
         to the American Red Cross Disaster Relief Fund. Our prayers go out to those affected by last 
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         prepare for combat. 

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         *** Aerotech is looking for your best microbial photograph for use in an upcoming issue of 
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