The 5 Different Types of Air Purifiers And How They Work

Last Updated on: 15th September 2023, 08:57 pm

Air purifiers are perfect 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.

Here 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 as small as 0.3 microns. These filters can trap dust, pollen, pet dander, mold spores, and 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 with a large surface area. The pleated mesh of fibers is arranged to 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 from the air purifier. The air particulates are trapped by the air purifier through three different mechanisms: impaction, interception, and diffusion.

  • In impaction, particles get embedded in the fibers,
  • Interception occurs when particles stick to the fiber
  • In diffusion, particles smaller than 0.1 microns collide with other air particles, slowing 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 corona discharge.

different types of air purifiers

These charged particles 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 air purifiers is that the harmful contaminants remain in the room until they are cleaned up. The benefit of 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 a vacuum machine can clean.

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

Carbon Air Purifiers

Activated carbon has been around for many years for air and water purification. Activated charcoal is highly porous, giving it a large surface area for trapping indoor air pollutants.

HEPA filters are inefficient 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, making it highly porous and giving 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 efficiently destroys harmful germs, such as bacteria and viruses, in the air. UV technology cannot eliminate airborne particles, so it is generally used with a filter system.

The drawback of 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 ozone production 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 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 called ozone generators, produce ozone gas, which harms our health. The government or any health professional does not approve this air purifier. Ozone gas may trigger symptoms of asthma and may contribute to other respiratory problems.

Studies suggest that ozone can eliminate biological contaminants, but the ozone concentration 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 a mechanism known as silent corona discharge. In corona discharge, the device uses electric discharge to break down normal oxygen molecules in the air into single atoms. These single atoms combine with the oxygen molecules already in the air to generate ozone molecules.

If you want to buy 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 your requirements 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 to decrease the risk of germs transmission.