There are many valid uses for an air purification system. But just like other industries, common sense should rule the day. With the prevalence of online purchases and aggressive marketing online, it pays to be aware of some of the bad guys out there and what they are up to. (Check out our Tips to Buying the Right Air Purifier.)
Scam One: Hyped Medical Claims
This is particularly rotten, since air purifiers can help some medical conditions and physicians do recommend them. However, scammers will inflate or create benefits outright that no system can deliver, or at least not the cheap purifier they are selling.
The most common medical use for an air purifier is to help prevent asthma attacks and combat allergies. Allergens come in several “flavors” and, unless a “clean room” is established in the house, an air purifier alone is unlikely to do much good. This is because many allergens are carried into the house on clothing – every trip outside, every open window and every time a door is opened and closed, more allergens are introduced. Further, the allergens tend to settle out quickly into carpets and furniture, only to be redistributed in the air again when disturbed. This means the allergen-containing air never has a change to reach the air purifier at all.1
A sealed room with a good air purifier can be effective and many medical professionals will recommend this to help someone sleep. Claims that diseases can be cured by air filtration alone are simply that: claims, and claims without substance.2
Scam Two: Hyped Filtration Claims
Because air purifiers work by “catching” airborne particles, there will always be substances which can pass through, almost as easily as air itself. An air purifier will not remove toxic chemicals – these are smaller than even viruses. Claims that noxious fumes can be removed by filtration alone are false.3
Scam Three: Ionizers Work Better than Filtration
The principle behind ionizing substances in the air is to put a positive charge on the particle and then use electrostatic attraction to remove it by binding it to a negatively charged grid. The idea is sound but fails for several reasons. The first is that the grid soon becomes coated; in effect, painted with substances bonded to it. The second is the risk of creating new chemical entities. An electrical charge is a source of energy that can break up chemicals or cause them to bond to each other. This process is unpredictable and may generate things that are even worse than what went into the air purifier.4
Finally, a common ionizing method is to generate reactive ozone – a way to “bleach” the air. But ozone is itself a pollutant and lung irritant. Some states have even banned this type of unit.
If ionizing technology is included in an air purifier, it must be coupled with a good filter and maintenance is critical – improper cleaning or failing to follow a cleaning schedule is a quick route to no purification at all.
Scam Four: Exaggerated Filter-life Claims
Some companies will offer high-priced, extended-life filters or “forever” filters and claim they never need replacement. However, commonsense should tell you that particles that collect on a filter have to go somewhere. Just like a simple coffee filter, or the filter bag in a vacuum cleaner, the dust collected will eventually clog any filter the air travels through.
Companies cannot tell you ahead of time how long a filter will last without measuring the amount of airborne particulates in your application.
Scam Five: The “Miracle” Machine
A common demonstration of the effectiveness of an air purifier is to enclose it in a clear box that is foggy with cigarette smoke, turn the unit on and observe how quickly the smoke clears. The problem with this is that we don’t live in small boxes. The airflow rating on an air purifier is limited by the power of the fan motor and the porosity of the filter. The better the filter the harder it is to pull air through it. A combination of a poor filter and a weak motor looks good in the demo, but probably won’t meet your needs.5
One final consideration is that particles do not distribute easily throughout the house. An air purifier simply cannot draw and filter air at any great distance from the unit.
A new round of aggressive telemarketing (and email pitches) is worrying. High pressure salesmen will say whatever they need to to scare people about air quality and get them to purchase a nearly useless air purifier.6 Seniors or those newly diagnosed with a medical condition are the natural targets of these hustlers. Be wary. Like any appliance, an air purifier has its uses, but is limited by the realities of physics. It pays to ask questions and shop around.