The 5 Different Types of Air Purifiers And How They Work

Air purifiers are perfect devices for eliminating harmful pollutants and allergens like pollen, dust, and pet dander from your home’s atmosphere keeping the environment fresh and clean. There are different types of air purifiers available on the market and each type utilizes a different technology to work and purify your indoor air.

In this article, you’ll learn about the five different types of air purifiers and how each type works to clean the air you breathe.

Let’s dive in.

Table of Contents

Different Types of Air Purifiers

The 5 most common types of air purifiers are:

  1. HEPA air purifier
  2. Ionic air purifier
  3. Activated carbon air purifier
  4. UV technology air purifier
  5. Ozone air purifier

HEPA Air Purifiers

different types of air purifiers

HEPA air purifiers are becoming increasingly popular due to their high efficiency in purifying indoor air. HEPA stands for High-Efficiency Particulate Air. HEPA filters are made of very fine interwoven fiber material. This type of filter offers a large surface area for polluted air to pass through and get purified with the help of an internal fan.

HEPA air filters must meet the standard of removing 99.97% of air particles that are as small as 0.3 microns. These filters can effectively trap dust, pollen, pet dander, mold spores, and some bacteria. One of the advantages of using HEPA air purifiers is that they do not produce harmful byproducts such as ozone gas.

How do HEPA Air Purifiers Work?

The HEPA filters in these air purifiers are pleated mechanical filters that have a large surface area. The pleated mesh of fibers is arranged in such a way that they trap harmful air particles from the indoor air.

HEPA air purifiers use an internal fan to draw polluted air into the unit and expel clean air out of the air purifier. The air particulates are trapped by the air purifier through three different mechanisms such as impaction, interception, and diffusion.

  • In impaction, particles get embedded in the fibers,
  • Interception occurs when particles stick to the fiber
  • In diffusion, particles that are smaller than 0.1 microns collide with other air particles which slows them down when passing through the filter.

A HEPA filter may last for up to 2 to 3 years after which it will have to be replaced with a new one to purify the air effectively.

Ionic Air Purifier

Ionic air purifiers are also known as air ionizers or ion generators as they produce positively or negatively charged ions. Most ionic air purifiers create negatively charged particles through a method called corona discharge.

different types of air purifiers

These charged particles then combine with airborne particles such as dust and pollen making them too heavy to stay in the air. Eventually, these heavy particles fall onto the ground or attach to other surfaces such as carpets, windows, tabletops, or walls.

The disadvantage of using these types of air purifiers is that the harmful contaminants still remain in the room until they are cleaned up. The benefit of using ionic air purifiers is that these purifiers are filterless which helps you save money on filter replacements.

How do Ionic Air Purifiers Work?

The air ionizers send negatively charged ions into the air. These negative ions then attract the airborne particles causing them to become heavy and dense. These dense particles are unable to move or float in the air. Hence, the bound particles settle on various surfaces around your home that can be cleaned by a vacuum machine.

Also read Ionic air purifier vs. HEPA filter: Which should you choose?

Carbon Air Purifiers

The use of activated carbon has been around for many years for air as well as water purification. Activated charcoal is highly porous which gives it a large surface area for trapping indoor air pollutants.

HEPA filters are not very efficient in capturing gaseous air particles such as VOCs. The VOCs (Volatile Organic Compounds) are chemical pollutants that are a source of odors that are released from furniture, paints, or cigarette smoke

Activated carbon filters, also known as adsorbent filters, are great at capturing gases, chemical contaminants, and bad odors present in the air. These contaminants can not go back into the air after they are captured by the filter thus avoiding recontamination of the atmosphere.

How do Activated Carbon Air Purifiers Work?

The carbon in this type of air purifier is processed which makes it highly porous and gives it a large surface area. The pores have a high absorptive capacity due to which the activated carbon filter absorbs and traps unwanted gases and odors through a process known as adsorption. The air purifier then releases clean and purified air out into the surroundings.

UV Technology Air Purifiers

different types of air purifiers

UV or Ultraviolet lights are known to have amazing germicidal properties. Air purifiers that employ UV technology have a UV lamp inside the unit. UV light is efficient in destroying harmful germs such as bacteria and viruses present in the air. As UV technology is unable to eliminate airborne particles, it is generally used together with a filter system.

The drawback of using UV technology in air purifiers is that it produces harmful ozone as a by-product which can pollute your indoor environment. Therefore, a good air purifier should minimize the production of ozone by using safe wavelengths of UV light as ozone is generated at only certain wavelengths of ultraviolet light.

How do UV Air Purifiers Work?

UV air purifiers have a UV lamp embedded in the unit. The air purifier draws air into the device and microorganisms present in the air are exposed to the UV rays emitted by the UV lamp. UV light disrupts the genetic material of these germs by breaking the molecular bonds in their DNA. This process destroys harmful pathogens such as bacteria and viruses and helps disinfect the indoor air.

Ozone Air Purifiers

Ozone air purifiers also referred to as ozone generators produce ozone gas which is harmful to our health. This type of air purifier is not approved by the government or any health professional. Ozone gas may trigger symptoms of asthma and may contribute to other respiratory problems.

Studies suggest that ozone can eliminate biological contaminants, but for that, the concentration of ozone would have to exceed the public health limit. Ozone air purifiers are ineffective in eliminating airborne particles such as dust and pollen from the air. Therefore, ozone is not recommended for indoor air purification.

How do Ozone Air Purifiers Work?

Ozone air purifiers generate ozone by using either ultraviolet radiation or by a mechanism known as silent corona discharge. In corona discharge, the device uses electric discharge to break down normal oxygen molecules that are present in the air into single atoms. These single atoms then combine with the oxygen molecules already present in the air to generate ozone molecules.

If you’re interested in buying an air purifier read the 12 best large-room air purifiers with washable filters.


So which type of air purifier should you buy for your home? The answer depends on what your requirements are and what function you want your air purifier to perform. It is recommended to use HEPA air purifiers over ionic purifiers as HEPA filters effectively clean the air from all airborne pollutants.

Go for an activated carbon purifier if you want your indoor air to be free of bad odors or smoke. Moreover, UV air purifiers would be the best option if you want to decrease the risk of germs transmission.