Indoor air quality is becoming a growing concern for many people. With air pollution levels on the rise, more and more individuals are turning to air purifiers as a solution. However, with so many types of air purifiers available on the market, it can be overwhelming to choose one that suits your needs. In this review article, we will be looking at some of the different types of air purifiers and which one might be right for you.

Types of Air Purifiers

HEPA Filters

High-Efficiency Particulate Air (HEPA) filters are widely used in air purifiers due to their ability to capture small particles such as dust, pollen, and pet dander from indoor air. However, they also have some drawbacks. Let’s explore the pros and cons of HEPA filters.

Pros of HEPA Filters

  • Highly effective at removing small particles: HEPA filters can capture 99.97% of particles 0.3 microns or larger, making them effective at removing common allergens like pollen, dust, and pet dander.
  • Can improve indoor allergies and asthma symptoms: By reducing the allergen load in the air, HEPA filters can help alleviate allergy and asthma symptoms.
  • No harmful byproducts: Unlike some other air purifying technologies, HEPA filters do not produce harmful byproducts during the filtration process.

Cons of HEPA Filters

  • Can be noisy: Due to their powerful motors, HEPA filters can generate noise, which may be bothersome in quiet spaces.
  • Filters need regular replacement: HEPA filters require regular replacement, usually every 6-12 months, to maintain their effectiveness.
  • Not effective against odors or certain chemicals: HEPA filters are not designed to remove odors or volatile organic compounds (VOCs), which may require additional filtration methods like activated carbon filters.

HEPA filters can be an effective solution for improving indoor air quality by removing allergens and small particles. However, they may not be suitable for addressing odors or certain chemicals. When considering an air purifier, it’s essential to evaluate your specific needs and choose a device that combines HEPA filtration with other technologies, such as activated carbon filters, to address a broader range of air quality concerns.

Activated Carbon Filters

Activated carbon filters are a popular choice in air purifiers due to their unique ability to adsorb impurities, including volatile organic compounds (VOCs), cigarette smoke, cooking smells, and musty odours. Unlike HEPA filters, which work by trapping particles, activated carbon filters work by adsorption, a chemical reaction where certain particles are attracted to activated carbon and bond with it. Let’s delve into the pros and cons of these filters.

Pros of Activated Carbon Filters

  • Effective at removing unpleasant odors: Activated carbon filters excel at removing odors, making them a great choice for kitchens, bathrooms, or any space where odors are a concern.
  • Long-lasting: Compared to other filter systems, activated carbon filters tend to last longer, making them a cost-effective choice in the long run.
  • Silent operation: Unlike some air purifiers that can be noisy, activated carbon filters operate silently, making them ideal for bedrooms, offices, and other quiet spaces.

Cons of Activated Carbon Filters

  • Affected by humidity: In high-humidity environments, the absorptive power of activated carbon filters can decrease faster, requiring more frequent replacement.
  • Potential for skin irritation: If not changed regularly, activated carbon filters can potentially cause skin irritation problems.
  • Limited impact on allergy symptoms: While activated carbon filters are excellent at removing odors and gases, they do not significantly improve allergy symptoms as they do not filter out allergens like pollen or dust mites.

Activated carbon filters can be a great choice for removing odors and gases from your indoor environment. However, they may not be the best choice if your primary concern is allergens. As always, it’s important to consider your specific needs and circumstances when choosing an air purifier. For the best results, consider an air purifier that combines activated carbon filters with other filtration technologies, such as HEPA filters, to address a broader range of air quality concerns.

Ultraviolet Germicidal Irradiation (UVGI)

Short-wavelength ultraviolet (UV-C) light is used in ultraviolet germicidal irradiation (UVGI) to kill or inactivate microorganisms by damaging their DNA and nucleic acids, which stops them from performing important cellular functions. This technology is used in a variety of applications, such as food, air, and water purification. Let’s delve into the pros and cons of UVGI.

Pros of UVGI

  • Wide range of applications: UVGI can be used in a wide range of settings to prevent the spread of airborne diseases. It’s commonly used in hospitals, laboratories, and workplaces where sterilization is crucial.
  • Low maintenance: Compared to other filter systems, UVGI requires less maintenance, making it a cost-effective choice in the long run.
  • Highly effective at removing germs, bacteria, and viruses: UVGI is highly effective at killing or inactivating microorganisms, making it a powerful tool in improving indoor air quality.

Cons of UVGI

  • Not designed for odours or chemicals control: UVGI is primarily designed to kill or inactivate microorganisms. It does not remove odours or control chemicals in the air.
  • Concerns with long-term exposure to UV-C: Long-term exposure to UV-C radiation can be harmful to humans and animals. Therefore, UVGI systems must be designed and used properly to ensure safety.
  • May emit ozone: Some UVGI systems may emit ozone, a lung irritant. It’s important to choose a UVGI system that does not produce ozone or ensures that ozone levels remain within safe limits.

UVGI can be a powerful tool in improving indoor air quality by killing or inactivating microorganisms. However, it’s not a one-size-fits-all solution. It’s important to consider your specific needs and circumstances when choosing an air purifier. For the best results, consider an air purifier that combines UVGI with other filtration technologies, such as HEPA filters or activated carbon filters, to address a broader range of air quality concerns.

Ozone Generators

Ozone generators are a type of air purifier that work by releasing ozone into the air. This ozone then reacts with pollutants, such as volatile organic compounds (VOCs), smoke, mold, and fumes, neutralizing them and improving the quality of the indoor air. However, like all air purifiers, ozone generators have their pros and cons. Let’s take a closer look.

Pros of Ozone Generators

  • Effective at removing strong scents and chemicals: Ozone generators are particularly effective at neutralizing strong odors and chemicals, making them a good choice for spaces where these are a concern.
  • Energy efficient: Compared to some other types of air purifiers, ozone generators require less energy to operate, which can result in cost savings over time.

Cons of Ozone Generators

  • Potential health hazards: Ozone can pose health risks, particularly to the respiratory system, when concentrated in high levels. It’s important to use ozone generators responsibly and to ensure that ozone levels remain within safe limits.
  • Can damage materials over time: Over time, ozone can damage certain materials, including wood, rubber, and electrical equipment. This is something to consider if you’re thinking about using an ozone generator in a space with these materials.
  • Requires time before re-entry: After using an ozone generator, you’ll need to wait a significant amount of time before re-entering the space. This can be inconvenient, particularly in spaces that are frequently used.

Ozone generators can be effective at neutralizing strong odors and chemicals, they also come with some significant drawbacks. It’s important to consider these pros and cons, as well as your specific needs and circumstances, when choosing an air purifier. As always, for the best results, consider an air purifier that combines multiple filtration technologies to address a broad range of air quality concerns.


There is no one-size-fits-all approach when it comes to choosing an air purifier. Each type of air purifier has its pros and cons, depending on your specific needs. HEPA filters are ideal for individuals who suffer from allergies or asthma, while activated carbon filters are great for eliminating unpleasant scents. Ultraviolet Germicidal Irradiation Technology is perfect for preventing the spread of airborne diseases, while ozone generators are efficient at battling strong odors. Ultimately, consider what you need most out of an air purifier so that you choose the right one based on your requirements rather than just going blindly by peer recommendations.


1) What factors should I consider when choosing an air purifier?
Answer: When choosing an air purifier, factors to consider include the size of the room, type of filtration system (HEPA or activated carbon), noise level, maintenance requirements, and cost.

2) Is a HEPA filter necessary for an effective air purifier?
Answer: A HEPA filter is considered one of the most effective types of filters for removing small particles from the air. However, other types of filters such as activated carbon can also be effective at removing gases and odors.

3) How often do I need to replace the filter in my air purifier?
Answer: The frequency at which you need to replace your air purifier’s filter depends on several factors including usage time and how polluted your indoor environment is. Most manufacturers recommend replacing filters every 6-12 months.


Hey there, I'm Kevin, editor of Xievo. I'm passionate about air purifiers and providing accurate information to help readers make informed decisions. In my free time, I love hiking and experimenting with air purifiers in my own home. Thanks for visiting Xievo!