Generally, the phrase “air purification” is synonymous with health. Why would anyone purchase an air purifier if they weren’t interested in making their breathing environment healthier? Many consumers don’t know that some air purifiers have hidden dangers. Air purifiers that emit ozone, either intentionally or as a byproduct, pose risks to human health and the environment.
Ozone is a molecule formed by three oxygen atoms. Ozone is found in two places:
- Atmosphere: Ozone naturally exists in a ring in the upper atmosphere. It protects the earth’s surface from ultraviolet light and is beneficial.
- Ground Level: Ozone also exists closer to ground level, which is harmful to all living things. Common sources of ozone include pollution, aerosols, refrigerants, and office printers.
To use a phrase coined by the Environmental Protection Agency (EPA), ozone is “good up high bad nearby.”
Types of Air Cleaners That Emit Ozone
Air purifiers that emit ozone purposefully are known as ozone generators. Ozone air purifiers are often marketed as having “activated oxygen” or “trivalent oxygen,” which is misleading because it confounds dangerous O3 with harmless O2. There is evidence that ozone has minimal purification ability, best suited for industrial cleaning in abandoned spaces.
The problem is that for the air to be cleaned, ozone must be pumped out at an unhealthily high level. Closed indoor environments are more quickly filled with ozone. Studies have shown that a room with one of these machines can swell to ozone concentration over the World Health Organization’s (WHO) recommendation of <60 ppb in less than an hour.
Ionizers & Electrostatic Precipitators
Some traditional air purifiers emit lower ozone levels as a byproduct of cleansing. While they typically produce less ozone than ozone-generating models, they pose a health risk. It is important to note that not all ionizers and electrostatic precipitators emit ozone. California’s Air Resources Board provides an incomplete but useful list of ozone-emitting air purifiers on the market.
Personal Air Purifiers
Personal purifiers are small gadgets designed to be worn around the neck, in a shirt pocket, or on the lapel. These products are largely being phased out of the marketplace but are worth mentioning. There is no evidence that personal air purifiers make any positive difference in air quality; many are dangerous. Essentially, the device shoots fresh air into the breathing area of the wearer, around their mouth and nose. Like home ionizers, these pint-sized purifiers produce negatively charged ions; ozone is emitted as a byproduct. A scientific study by Phillips of the EPA found that ozone levels with these products exceed the safety level accepted in the U.S.
How are humans affected by ozone?
Overwhelming scientific evidence shows that ground-level ozone is bad for health. Heavy concentrations of the compound harm the respiratory system and worsen existing breathing ailments. As with most health hazards, children, elderly people, and those already ill are the most vulnerable. The EPA Agency reports that relatively low amounts of inhaled ozone can permanently damage the lungs and “cause chest pain, coughing, shortness of breath, and throat irritation.” Ironically, those with the most faltering health often purchase ozone purifiers.
Air purifiers that use ozone emit deceivingly fresh-smelling air, which makes them seem intuitively good for health. Think of ozone as invisible, odorless smoke…something you want to avoid inhaling. Ozone purifiers negatively charge particles in the air, making them stick to walls and ceilings. Countless testimonials can be found online from unwitting customers complaining about the “black wall effect” caused by accumulated particles from running an ozone air purifier.
How does ozone affect the environment?
Excess ozone also has adverse effects on plants. It stunts plant growth and can cause their leaves to develop red discoloration. These results are particularly significant in regard to agriculture because high ozone concentrations in the environment can cut crop yield by large fractions.
Ozone air purifiers stay on the market despite being toxic to the environment. Manufacturers exploit the fact that most consumers need to be more well-educated about ozone, and purifying units are very cheap to make.
The State of California recently passed regulations that force ozone air purifiers to limit their ozone emissions to a healthy level. Manufacturers must comply with these limits and have their products tested and certified by California’s Air Resources Board by October 2010. This may be a step towards ultimately banning all products that emit ozone.
Safer Alternatives to Ozone
There are many, much more effective technologies available to purify the air. The use of ozone is simply impractical and inefficient! Any ozone air purifier is antithetical to people interested in improving the air quality around their house or office. To truly purify the air and remove any particles, mechanical filtration is the way. Common alternatives cleaning technologies include:
- HEPA Air Purifiers: High-efficiency filters that remove at least 99.97% of particles .3 micrometers or more in diameter
- Carbon Air Purifiers: Smoke, odors, and chemicals are trapped in activated carbon granules
- UV Air Purifiers: Ultra-violet light acts as a germicidal, killing bacteria, viruses, and other germs