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Ozone - Nature's Air Purifier
Ozone - Nature's Air Purifier
by Charles W. Moore
Far from being the dangerous pollutant many assume it to be, ozone is actually one of nature's most potent air purifiers.
Most people these days are familiar with Ozone by name, especially since the upper atmosphere's protective Ozone layer began disappearing. However, conventional wisdom has it that while stratospheric Ozone is good, ground level Ozone is not. This is a simplistic misconception.
For people who suffer from allergies and environmental sensitivities, or folks who just have a musty, smelly basement, ground level Ozone can be a wonderful friend and helper. How? Well, far from being the dangerous pollutant many assume it to be, Ozone is actually one of nature's most potent air purifiers. The highest naturally-occurring ozone levels, about 0.05 to 0.065 parts per million (ppm), are found at the seashore, in forests, or in high mountainous areas - places people usually associate with healthy outdoor recreation - not pollution. The slightly pungent, but fresh and pleasant, aroma you may have noticed in the air after a lightning storm is Ozone, as is the distinctive smell of air-dried laundry (so long as it isn't drowned out by chemical perfumes in your detergent!). Average outdoor ozone levels in unpolluted areas are between 0.03 and 0.05 ppm.
When Oxygen molecules are split into two separate atoms by radiation, combustion, lightning, or man-made electric arcs, these freed atoms recombine in three-atom groups forming “mutant” cousins of Oxygen - or Ozone.
Ozone is indeed often present in smog, partly because many of the processes that create pollution also create ozone. As well, when sunlight shines on industrial and automotive pollution, oxygen atoms are hived off the molecules of those pollutants to form chemicals called peroxy radicals - baddies like nitrous oxide, nitric acid, sulphur dioxide, and carbon monoxide. Meanwhile the freed Oxygen atoms bond with free oxygen in the air and form Ozone. Ergo, the more pollution there is in the air, the higher the levels of Ozone formed, but Ozone itself is not the problem.
In fact it is part of the solution - without Ozone the pollution we pour into city air would render it uninhabitable. The highly reactive Ozone neutralizes pollution by recombining with peroxy radicals and breaking them down into water, carbon dioxide, nitrogen, sulphur, and oxygen. If we stopped pumping pollutants into the air, Ozone would clean up the ones that are already there.
This highly reactive quality of Ozone is why it is such a powerful and efficient cleaner and purifier. Ozone will react with almost anything, including chemical sources of unpleasant or hazardous indoor odours - about 99 percent of which are made up of “unsaturated” molecules that can take on additional molecules such as Ozone. However, the reactive Ozone molecule quickly proves too much for the pollutant to absorb, and it breaks up into its basic molecular components. The pollutant has been neutralized and the ozone molecule, having given up its unpaired third Oxygen atom in the process, becomes plain Oxygen again.
Bacteria, which cause mold and mildew smells, pet odours, many residual cooking odours, etc., are killed when they react with Ozone. Like chemical pollutants, the membranes or shells of bacteria contain unsaturated molecules which take on Ozone and are destroyed in much the same way as the chemicals are. Without its protective membrane or shell, the bacterium dies, leaving only Oxygen. Pretty much the same applies to fungi and viruses which are also killed by Ozone.
The means of putting this process to work cleaning the air in your home is a portable ozone generator. These machines come in various sizes, are designed to run continuously 24 hours a day, and feature adjustable Ozone output volume. Several brands are available, including machines made by Quantum Electronics Corp. and Living Air. My family has owned a Quantum Panda for the past three years, and we wouldn't want to be without it.
An important consideration when choosing an Ozone generator for home use is the electrical process by which it produces Ozone. Either A.C. or D.C. current will produce ozone, but because A.C. wall current switches polarity from negative to positive 60 times per second, it will generate both negative and positive ions. On the other hand, machines that rectify A.C. current to D.C. before it is fed to the Ozone generating plates, only produce negatively charged ions, and will not create harmful nitric acid, nitrogen dioxide, or nitrous oxide by-products, which can form when positively-charged ions are present. Incidentally, A.C. current doesn't exist in nature; sky-to-earth lightning is always negatively charged.
There is also an added bonus as a result of negatively charged ions being produced during D.C. Ozone generation. These negative ions attach themselves to positively-charged dust particles and smoke molecules in the air, causing them to sink to the floor. An excess of positive ions created by electric and electronic appliances in homes and offices has been related in studies to irritability, fatigue, and lassitude in humans sharing this airspace - part of the phenomenon known as “sick-building syndrome.” Negative ion creating Ozone generators help restore the natural negative-positive ion balance in the air as well as purifying it of pollutants. Living Air's XL-15 Ozone generator also features an internal radio-wave antenna that enhances its negative ion creating capability.
Is Ozone safe? Like virtually everything - even oxygen - Ozone can be harmful if you're exposed to too much for too long. The U.S. government's Food and Drug Administration (FDA) declares 0.05 parts-per-million as the safe level for 24-hour-a-day Ozone inhalation. This is an extremely conservative evaluation, since natural levels of Ozone, out at sea for instance, often reach 0.065 ppm - 25 percent higher than the FDA's “safety” limit. Recommended settings for small home Ozone generators maintain levels of about 0.03 to 0.05 ppm inside the home.
If you suffer from allergies or chemical sensitivities, an ozone generator can dramatically improve your quality of life. Quantum Electronics President Moe Lepenven supplied me with a thick sheaf of unsolicited testimonials from people who declare that owning a Panda machine dramatically changed their lives. Indira Hall of Air and Water Systems in Saskatoon, Saskatchewan, Canada tells me she got into the Ozone generator business after a Living Air machine got her off antibiotics and regular visits to the doctor for allergy attacks.
Charles W. Moore is a freelance writer who lives in rural Nova Scotia, Canada.
