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How to Choose an Air Purifier

Choosing an air purifier is a daunting task, especially if it's your first. Many buyers are disappointed when the product chosen does not seem to solve their particular problem. The air purifier industry is unregulated. There are really no standards, and what passes for standards is often self-serving. Many consumers are confused by the many technologies available, and will try to select a particular technology or brand right away. This may not be the best approach. The following points are a suggested analytical framework. First, the new product should do no harm. Lots of people are astonished to learn that many air cleaners emit harmful gasses. Ozone is used as a fumigant by professional mold premeditators. It oxidizes chemicals, odors and microorganisms when pumped into closed rooms in high concentrations. Air purifiers have evolved which emit chronic ozone, at lower levels. This has become popular, and many users like the fresh smell. Many also report improved allergy/asthma symptoms when using ozone emitting air purifiers. Ozone is a persistent chemical in indoor air, it accumulates and lasts for days, not hours or minutes as is often claimed. While these oxidants may kill lung dwelling microorganisms and thus relieve some people's symptoms, long term exposure to airborne oxidants is seriously dangerous. Everyone knows at least one beautiful person whose face has been ruined by a life of cigarette smoking. What causes those premature wrinkles, stiff, gray looking skin, and aged eyes? Airborne oxidants! Ozone may have value as an alternative medical therapy, but that is a whole separate issue. Chronic administration of an experimental alternative medical technique to millions of unknowing consumers is a dangerous fraud. Chronic ozone is not a suitable method of air purification. Many cheaper air cleaners use glues and soft plastics which outgases chemicals.

By elimination of ozone-prone and cheap plastic models, the search is narrowed considerably. Second, many people see dust accumulation on furniture and think of an air purifier as a means of reducing it. While a properly sized room air purifier will certainly do this, visible dust and most odors are not the real health threats. Often toxic chemicals are harmful at concentrations below our threshold of smell. Serious gas and odor removal is a requirement if health benefits are expected. This raises the cost considerably, so many air purifier vendors will try to hide their product's shortcomings. The "Clean Air Delivery Rate" (CADR) is one such subterfuge, it focuses on larger dust-sized particles and completely ignores gas poisons. New technologies, such as photo catalytic oxidation, show promise with chemicals, but the long standing favorite is activated carbon. There needs to be lots of it, not just a coating sprayed on foam prefilter. Choosing an air purifier with carbon measured in pounds narrows the list considerably, but raises the price. Third, particles much smaller than the eye can see are the real culprits. They pass through the lungs and get in the blood. Our technology grinds toxic materials into microscopic sizes, which build up invisibly in our living space. Many air purifiers, including some selling for very high prices, do not remove these tiny particles from our air. Quality construction is important; case, gaskets, seals, and precision fitting eliminate fine particle bypassing. Fourth, consider long term cost of ownership, not just initial purchase price. Some folks will take home an air cleaner only to discover that replacement filters, needed frequently, cost almost as much as the machine. This is called the cheap air purifier loss leader filter price ripoff. Filters should be independently replaceable. An all in one filter, with carbon and particle filtration combined, will need replacement when either media is clogged. There are many models with average service lives under two years. Buying these "bargains" is false economy. A quality purifier can last 10 or more years. Along with filter costs, energy use can add up. Air purifiers using over 100 Watts will add to the electric bill. Fifth, many air purifiers produce noise levels too high for practical use. Some quiet models have air flow rates to slow to do much cleaning. This is one big area of consumer complaints. The noisy machine may clean the air when running, but ends up turned off most of the time.

Bedroom noise levels need to be below about 34 decibels (dBA). Again, many vendors will hide behind assertions of "ultra-quiet" without being specific as to noise. Sixth, who is the builder? Are they also the vendor? Manufacturers should have a track record, with many units sold and a reputation for customer service. Today, new brands are popping up, and many US vendors are just importers of Asian made equipment. Will they be around when your chosen air purifier needs warranty service? Good air purifiers have warranties measured in years. A one year warranty is evidence of short product life or possibly financial distress. There is several very successful air purification products associated with multilevel marketing, scam marketing, or credit card ripoffs on returned merchandise. Fortunately most of these disreputable vendors are eliminated by guideline number one above: most of their products are not ozone-free. Last, is the air cleaner a good value? Is the product price supported by infomercial advertising, brand building, and hype? Or does the product stand on its own merits, the result of a long term quality engineering process? Air purifier buyers can increase their odds of success by following a plan in choosing an air purifier. The author, Justin H Carter, has air purifier experience dating back to 1987. He offers fact, opinion, and the most detailed Air Purifier Reviews. On the web at:

How to choose an air purifier  

Choosing an air purifier is a daunting task, especially if it's your first. Many buyers are disappointed when the product chosen does not se...