The indoor air in you home can contain more than five times the pollutants of the air outside. This is a stunning realization for a lot of people.

artistic smog To this we have to add the simple fact that we spend most of our time indoors. Some estimates say that as much as 90 percent of your time is spent in some room.

It is no wonder then that your body often reacts to the quality of air with sneezing, infections, itchy eyes, and various irritations.

Today more than ever, there is the need to improve the quality of your indoor air. One of the best ways to do so is using a quality air purifier.

But, not all air purifiers are created equal. To select the best types you would have to consider several important criteria.

Criteria for Selecting Air Purifiers

First you have to know what problem you would like to tackle. Do you want to deal with allergy problems, get rid of bacteria or viruses, or clean your indoor air from odors?

Allergies are caused by pollen particles with sizes from 0.3 micron or larger. So you would have to consider an air purifier with HEPA filter, which can effectively filter these particles.

However, the great majority of particulates are smaller in size than 0.3 micron. These particles include, for example, most of the germs and bacteria, house dust, or cat allergens. To filter these, you would need purifiers with charcoal filters, ultra-violet light, or ionic air purifiers.

The smallest particles include fumes, soot, smoke, and smog. Here you would want to use purifiers with activated charcoal, or ozone generators.

What if you have several problems combined?

For example, what if you want to get rid of allergens, but also you would like to get rid of odors?

In that case, you should use a system that combines several of the technologies described above.

Depending on your needs, you would have to check the following features:

Air Purifier Capacity

The price is very much dependent on the capacity of the cleaner. The greater the capacity, the greater the price. If you want to spend a couple of hundred dollars, your purifier will have the capacity to clean only one room at a time.

Take into account the fact that a lot of brands of air purifiers can be noisy when operating at the maximum power. Choose cleaners with ample capacity so that you won’t have to set them to work at the maximum setting.

Operating Expenses

There are air cleaners with expensive filters. You have to take this into account when buying your next air purifier. In general, the more sophisticated the filter is, the more expensive it is. And it will take more power to pull air through it. So the power consumption will go up. So, electricity consumption is another thing to look at.


Choose a reputable brand with a proper warranty. It does you no good to purchase an air cleaner for a couple of hundred bucks, only to have to pay a lot more to repair some part later.

Air Purifiers Brands

Some of the best players you should be looking for are these brand names: Austin, Allerair, Oreck, Honeywell, Whirlpool, Alen, Hunter, Ionic Breeze, Delonghi, IQAir, Friedrich, Blueair, Air-O-Swiss, Winix, Biozone, Hamilton Beach, Holmes, Calutech, Care, and Healthmate.

HEPA air purifiers - how cost effective are they?

HEPA stands for “High Efficiency Particulate Air”. It was first designed in the 40’s of the last century. HEPA was designed with a goal in mind to filter as many as 99.97 percent of particles larger than 0.3 micron (1 micron is the millionth part of a meter). The HEPA filters today still adhere to this standard.

Just to give you some comparison, the diameter of a human hair about 120 micron on average. So a particle of 0.3 micron is something like 300 times smaller. This sounds great, doesn’t it?

Important considerations

There is no question that HEPA filters will do their job filtering allergens, dust, or mold. But, they are not so effective when it comes to particulates smaller than 0.3 micron.

This effectively means that viruses, bacteria, smoke, dust mite, fumes, smog, and germs won’t be filtered.

It is only fair to mention that a HEPA air purifier will remove some of the particles smaller than 0.3 micron (some are able to filter a portion of particulates smaller than 0.01 micron), but the efficiency of the process of removal goes down steep with particle size.

Some of the more expensive purifiers on the market are capable to do a better job, though.

For example, the IQAir’s HyperHEPA system of filtration, as installed in the IQAir HealthPro Plus is tested to remove 99.5 percent of all particulates down to 0.003 microns. That’s 100 times better than the standard HEPA. This filter is going to last for at least several years without replacement.

Downsides of HEPA

  • The filter should be replaced every two to five years. A prefilter could extend this period.
  • The filter is not cheap. The price range is somewhere around 50 dollars.
  • HEPA air purifiers operate by moving large quantities of air through a dense HEPA filter. It takes a lot of power to be able to do that. This reflects on your electricity bill. The actual costs are somewhere between 10 and 30 dollars per month.
  • HEPA cleaners can be rather noisy, especially if you run them at maximum power.
  • The filters are highly fragile, so extra care is needed to keep them intact.

A number of air cleaners based on the HEPA technology also use other cleaning technologies in parallel to HEPA.

For example, if you want to remove odor, a gas filter of activated carbon is added. The alternatives could be using a filter of zeolite, or permanganate. An example of such models of cleaners are Austin Air HealthMate, which uses Activated Carbon and Zeolite to remove gases and odors in its stage 3 filtering.

I hope you’ve seen that HEPA air purifiers have some downsides, as well as advantages when it comes to their cost benefit ratio. HEPA is still considered one of the best technologies to improve the quality of your indoor air.

Some of the best brands you would want to consider for your new purchase are Holmes, Honeywell, Austin, and IQAir.

Image credit: Flickr Creative Commons: Doodlecarll