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Fans, Vents, or Filters? The Truth About Air Purifiers

If you suffer from asthma or allergies, have furry pets, or are sensitive to dust, cigarette smoke, and other irritants, you’ve probably noticed the extremely effective marketing of air purifiers. If they work as they say, clean, breathable air could be yours with one swift purchase!

But do air purifiers work? Do you need purifiers if you already have central air or ventilation fans in your bathroom? Below we explore the truth about air purifiers and other air-cleansing methods.

The Concept Behind Air Purifiers

Air purifiers are supposed to improve air quality by removing contaminants from the air. Contaminants include pollen, pet dander, cigarette smoke, and dust. These contaminants make it difficult for people to breathe, particularly people with asthma or allergies.

What Research Says about Air Pollutants

According to the EPA, the best way to keep the air clean in your house is to regularly clean the surfaces to remove pollutants that would otherwise get into the air. On top of this, increasing air circulation is an effective way of keeping contaminants from sticking around. There is no evidence that cleaning the air of pollutants reduce symptoms of asthma or allergies, particularly when allergens often settle in the carpet, on bedding, and on hard surfaces. Air purifiers do not eliminate the need for regular vacuuming of carpets, washing of sheets, and dusting of hard surfaces. They also are generally not effective at removing moisture or chemicals from the air, unlike bathroom fans which are specifically made for this purpose.

Different Types of Air Purifiers

There are two main types of air purifiers, and many variations on them. High Energy Particle Air purifier filters (also known as HEPA purifiers) are installed into your ventilation system. The installation and maintenance for HEPA purifiers is expensive, but these purifiers can be extremely effective. They increase the air circulation of your home and successfully remove small contaminants.

There are also small stand-alone units that you can simply plug into your electrical outlets. These are much more affordable, but are less reliable. There is no standard certification for them, and quality and effectiveness varies widely. Among these standalone units, many use words like ionic, ionizing, and electrostatic. These purifiers work using chemical reactions that produce ozone. At close proximity, ozone can be harmful to humans and aggravate health conditions like asthma and allergies. Many health professionals recommend keeping kids away from ionizing air purifiers, as they can harm their sensitive lungs.

Alternate Methods of Improving Air Quality

So some air purifiers are effective, particularly HEPA purifiers. However, these are expensive both in upfront installation costs and ongoing energy costs. They also require replacement and repair on a regular basis. Luckily, there are more affordable ways of improving the air quality of your home.

Exhaust Fans

Exhaust fans are an effective way of circulating air in and out of rooms. Bathroom ventilation fans in particular are very effective, as they remove most air from what is usually a small enclosed space. Removing this air prevents mold and mildew buildup. Over time, mold can cause severe health issues, including breathing difficulties. Preventing mold is one of the most effective ways of protecting your family’s overall health, and is simple to do with regular cleaning and effective ventilation.


It’s surprising to some, but according to the EPA, the average indoor air quality is four to five times worse than outdoor air quality. This is because air inside the home becomes stagnant and pollutants build up. You can increase airflow through your home by having exhaust fans that vent the air outside and adding semi-controlled ventilation, which brings outside air into your home in addition to sending indoor air outside.


Most homes today have central air systems. It’s important to make sure that the filters on your furnace or in your air vents are replaced on a regular basis. If filters are full of dirt and allergens, they can’t effectively keep your air clean. Filters are more cost effective than air purifiers, as well as energy efficient. They also don’t put anything into your air like ozone, but simply keep things out. So in combination with proper fans and ventilation, they are much more effective than air purifiers.

When considering making improvements to your home, it’s important to do your research and make sure that the methods you choose will be effective and efficient. Air purifiers sound like a lifesaver, but they are more expensive and less effective than simple exhaust fans, air filters, and proper ventilation.