Air Purifier Buying Guide

Indoor air is often much dirtier than outside air because we spend so much of our time in the indoor environment. AS a result, particles in the air, such as pollen, dust, chemicals, mold, and bacteria can cause problems for people with sensitivity to allergens or chemicals. Air purifiers work as filters for the air, removing the particles that would otherwise get into your lungs and on your skin. Keep in mind the type of particles you are trying to filter out when you decide what air purifier to buy.

Types of Air Purifiers


Standing for high efficient particulate air, HEPA have a standard to meet. That standard is trapping at least 99.97% of all particles larger than 0.3 microns. Because they can trap mold and bacteria, HEPA air purifiers make the environment safer and healthier. They also do not produce any by-products.

Activated Carbon

This type of air purifier uses a type of carbon that has processed to make it very porous and also has a large surface area. First used to purify water and remove color from sugar, activated carbon is also used in gas masks and wartime water and air purifiers. This type of air purifier is especially good for people with multiple chemical sensitivity. They are also great for asthma sufferers as the activated carbon removes all chemicals from the air. However, they are less effective in removing allergens from the air.


Excellent at destroying germs and bacteria, UV air purifiers usually have a particulate filter as well. This is because the UV lamp cannot remove particulates from the air and, without removing the particulates, too many germs and bacteria cells are shaded form the light and thus cannot be eliminated by the lamp.

Negative Ion

Negative ions are basically oxygen atoms that have gained an electron. They can magnetically attract pollen and other air particles until the particular formed by the air particle and the negative ion are too heavy to remain in the air. This causes the particle to fall and attach to something solid in the room, such as a window seal or piece of furniture. Negative ion air purifiers do not have the ability to eliminate air particles, so the particles that attach themselves to windows, walls, or furniture have the ability to get loose and recirculate into the air. IN this way, the negative ion air purifier does not truly clean the air and simply masks the problem.

Pay Attention to

Room Size

Calculate the square footage of the room you want to purify, and then look for an air purifier with a required square footage at least as much as that of the room. If you have asthma or allergies, you will also want to consider the air change per hour rate. This refers to the number of times per hour a given air purifier can clean the air. An air purifier that can clean the air at least four times per hour is the best choice for someone who suffers from asthma or allergies.


In most cases, it is recommended that you place your air purifier in your bedroom, which is where you spend the majority of your time. If, however, you spend more time in the living room, placing the air purifier in there would be the best case scenario. Keep in mind that even portable air purifiers are intended to purify only one room's air. If you need to purify more than one room's air, you should invest in additional air purifiers.

Special Features

Once you have determined where you are going to place the air purifier and the right unit for the space it will be in, you should determine if you desire any special features. Such features can include castor wheels and handles for mobility, digital controls, remotes, and filter change indicators. There are many features to choose from, but the more special features you get the more expensive the unit will be.


If your air purifier has a filter, it is highly recommended that you change it according to the manufacturer's filter change intervals. This will maintain the air purifier's high level of particle elimination. If your unit has multiple filters, you will likely have to change them at different times. However, some units come with combination filters that are easier to remember to change because there is only one schedule to remember. UV lamps on air purifiers do not need to be changed, making them more convenient for the user.

Top Brands and Product Lines


Celebrating 110years of innovation in 2016, Honeywell is a company that focuses on inventing and manufacturing products that address some of the world's most serious problems, from global urbanization to safety and security. One of their products is the Whole-House Media Air Cleaner. This air purifier uses a negative ion filter and is installed into the air ducts of a home or business to purify the air in all the rooms.


Another company that has just celebrated a hundred years in business is Whirlpool, the number one worldwide producer of appliances for home and business. Whirlpool manufactures everything from clothes washers to water and air purifiers. The Whispure air purifier has a three-stage filtration system. It uses a pre-filter, a carbon filter, and a HEPA filter, all of which need to be changed every four months.


Founded in 1989, Coway focuses mainly on home wellness electronics. A Korean company, they export to sixty countries worldwide and have a goal of becoming the number one home wellness company in the world. Its diverse line of products includes water filters and air purifiers. Their air purifiers have been certified by Energy Star. The HH Mighty air purifier from Coway has a compact size and uses a four-part filtration system. It also has both an air quality indicator and a filter change indicator.


Started as one engineer's mission to find an air purifier for his asthmatic son, Oransi is a dedicated air purifier company. Their air purifiers use both HEPA and activated carbon filters and are certified by Energy Star. The Max Best air purifier is designed for rooms up to 600 square feet and has a three-stage filtration system of a pre-filter, HEPA filter, and activated carbon filter. Special features include a filter change indicator and a dust sensor.