HEPA Air Purifiers Info

As good as HEPA air purifiers sound, they cannot remove gasses, chemicals, or odors. Consider that these are molecular level substances, and that the 0.3 micron holes are actually quite large compared to gas molecules. To compensate for this, most HepA air purifiers have some type of activated carbon based material that will absorb chemicals and odors. There are a number of different varieties of activated carbon that is included in most HEPA air filters. For example, the Air-O-Swiss unit has a thin mat in it to cancel out smells. In the Austin Air Purifier, there are pounds of activated carbon that do the same job. Regardless of the form, the carbon absorbs the gasses that would otherwise not be caught by HEPA air filters. These chemicals usually either cause unpleasant odors, or are possibly dangerous, harmful gasses.

Worth mentioning is the Blueair product line. The Blueair product line uses a different approach to HEPA. Not only do they provide a large surface area for air to pass through in their products, but they also have much larger openings in their filters, which are polymer based. This allows the Blueair to use a much smaller and less noisy fan and still achieve far more airflow. To compensate for this, these air purifiers use electrostatic brushes in the airflow just before the HEPA element. The result is that the pollution particles are charged electronically and end up getting stuck to the filter media, despite the larger passageway and increased air flow.

HEPA filter air purifiers are actually quite simple, in reality. A fan shoves airflow through a filter. As the same air passes back through the filter, it gets purer and purer. Therefore, the bigger the room, the bigger the product. Another approach, though, is more small air purifiers, which tend to work better. Think of a long, narrow room. If you put HEPA air purifiers at each end, the air only has to move half as far as if you were to put one larger purifier at one end, or even in the center. This results in cleaner air as not only does more air get treated, but the same air gets treated repeatedly, far more often than with just one of the HEPA air filters. Many times, the price is either comparable or better, and if a problem develops in one of your HEPA air filters, you only lose one and still have one small one in operation until you’re able to replace or repair the other.

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Activated carbon in HEPA air purifiers may seem strange to you, unless you own a water purification system which uses carbon or are an aquarium hobbyist. Even so, you may not understand exactly what it is activated carbon does.

For most people, though, the first time they encounter activated carbon will be in choosing HEPA air purifiers. Most customer begin their search for air purifiers due to asthma or allergies. As they learn more about HEPA air purifiers, though, they’ll learn that many of their respiratory problems come from chemicals and odors in the room. Therefore, most quality HEPA air purifiers are designed to address the chemicals and odors as well as the allergens themselves.

Believe it or not, humans were using activated carbon to purify water as many as two centuries ago. Even back then, we knew of activated carbon’s exceptional absorption qualities. It was not until the early 1900’s, though, that the stuff was produced in a form that could be sold commercially. Produced commercially, activated carbon was sold as powder. Back then, it was used only to remove smell or taste from water and to remove the color from sugar. As World War I got into full swing, we discovered that activated carbon could be used in gas masks to protect soldiers from chemical agents in the air. Not only that, but it was used for war time water and air purifying. At this point, instead of being used in powder for, it was used in a granular form. This was the beginning of activated carbon being used in many ways.

You’re probably wondering why we’re referring to this carbon as “activated.” Is there such a thing as non-activated carbon? Well, the heat used in “activating” the carbon is what drives out the impurities in the carbon itself. This leaves a place for the impurities in whatever it is the carbon is cleaning to reside. So activating carbon is kind of like emptying a sponge, only with head instead of pressure. After activated carbon becomes full, it can actually be reactivated by re-heating it. This is, however, not a good idea, and is considered dangerous and impractical. Non-activated carbon is basically charcoal or soot.

There are a variety of types of activated carbon, and it is described in a variety of ways, but generally activated carbon includes a wide range of amorphous carbon-based materials. These materials have a high degree of porosity (lots of holes) and a relatively large surface area. Basically, this means it has excellent absorbent characteristics. These absorbant characteristics are why activated carbon works so well filtering air and water both.

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Activated carbon is also often combined with other minerals like zeolite, especially in HEPA air purifiers. Zeolite absorbs molecules and ions, acting as a filter for toxin removal, odor control, and a sort of chemical sieve. In some HEPA air purifiers, the carbon may be blended with impregnated active alumina, or may itself be impregnated with potassium iodide. This procedure will increase the substance’s absorbent qualities. Those HEPA air purifiers are especially good for people with Multiple Chemical Sensitivity, otherwise known as MCS, as they absorb the formaldehyde that is often found in furniture upholstery, carpet, and wood paneling, among other things. Chemicals in household cleaning items as well as perfumes are also extracted, leaving the air much more breathable for all those concerned, but especially babies, the elderly, and asthma sufferers.

The amount of activated carbon, as well as the type and other things with which it is blended, as well as how it is used in HEPA air purifiers depends largely on the model and brand of the HEPA air purifiers.

For example, the Austin Air HM400 uses 18 pounds (!) of granular activated carbon impregnated with zeolite. The zeolite enhances the chemical absorption qualities fo the activated carbon.

The Austin Air HM400 SuperBlend also contains 18 pounds of granular activated carbon, but it is impregnated not only with zeolite, but also potassium. This makes it effective at removing formaldehyde.

The Blueair 501 and 601 systems contain three integrated HEPA air filters. Unlike Austin Air, Blueair does not specify the weight of the carbon included. The optional SmokeStop filters have a lot more activated carbon than the standard filters that the unit comes with, though.

The V-5 Cell filter in the HealthPro Plus by IQAir has a five filtration chamber that includes a blend of activated carbon, as well as impregnated active alumina. This provides for enhanced absorption. Like Blueair, IQAir does not tell us the weight of the activated carbon that is in their HEPA air purifiers.

In most cases, pollens and pet dander are the main things that people are concerned about when buying HEPA air purifiers. Odor and chemical absorption are often less important, if they’re important to the consumer at all. Some, though, may be looking for a high degree of both. for those people it is best to look for high caliber HEPA air purifiers that offer outstanding odor, chemical, and particle removal. Volatile organic compounds, known as VOC’s, such as ozone, pets, tobacco, smog, and even cooking can be irritating or downright unhealthy for anyone, not just asthmatics and those with bad allergies.

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