What is a UV-C Light Filter? UV-C Types, Pros & Cons

uvc light filter

UV-C light is a particular type of photocatalyst that emits ultraviolet (UV) rays, such as the Sun. When this ray hits certain materials, like mercury or titanium dioxide, it changes into hydrogen peroxide and hydroxyl radicals.

The hydroxyl radicals then break down odor molecules into smaller components that are less hazardous to human health. UV-C light filter is used in an air purifier to kill germs and remove odor.

Also Read About: Why Is Indoor Air Pollution Worse

Types of UV-C Rays

The best thing about this type of filtration is that it can be safely divided into three types;

  1. Germicidal
  2. Photooxidative (PO)
  3. Photocatalytic (PC)


Germicidal uses UV-C rays to immediately destroy microorganisms such as bacteria and viruses by destroying their DNA. This method is highly effective but not safe enough to use on humans.

That’s why most germicidal lamps only emit ultraviolet rays and they can penetrate cells more efficiently at this wavelength. These air purifiers are typically used in hospitals clean rooms, including bathrooms, to kill germs.

PhotoOxidative (PO)

It has the same mechanism as germicidal, except that it works by releasing free radicals instead of UV rays. Free radicals are high-energy molecules containing oxygen atoms with an unpaired electron. They’re extremely unstable and react readily with other molecules, causing damage to cells or even killing them.

Furthermore, the PO lamp contains a special coating made from either titanium dioxide or barium oxide, activated when exposed to UV light. This coating creates hydroxyl radicals through photo-ionization. It is the process where ultraviolet photons eject electrons from matter and ionize gas atoms in the air purifier.

PhotoCatalytic (PC)

It is also a photocatalyst, the type of air purifier with a UV-C light filter most widely used in households. It’s safe for humans because it doesn’t emit ultraviolet rays but catalyzes them upon exposure to special metals like titanium dioxide or aluminum oxide.

PC lamps contain a membrane often made from zirconium phosphate, aluminum oxide, titanium dioxide, or barium sulfate. When it is exposed to sunlight (ultraviolet rays) or an artificial lamp (UV-C), the membrane releases hydroxyl radicals via electron transfer between excited molecules on metallic particles and ground-state molecules on non-metallic surfaces.

Advantages of UV-C Light filter Air Purifier

benefits of uvc light filter air purifier

UV-C light filter is a useful feature that can help you get rid of harmful microorganisms from the air. In addition, UV bulbs give more benefits to improve the quality of indoor air. Here are 4 advantages of using a UV-C bulb:

1. Eliminates Germs and Bacteria

The use of ultraviolet light to kill germs and bacteria has been known for a long time. However, many people do not know its usefulness because it kills only some types of bacteria without affecting others. It provides germicidal effects on specific pathogens such as monellia , helicon pylori, and legionella.

UV-C light emits intense energy that can kill bacteria, germs, and other pathogens without causing chemical reactions. Remember that ultraviolet radiation can damage your skin if you are exposed for a prolonged period. However, this risk is eliminated when inside an air-purifying machine because most machines have fans that quickly move the air.

2. Eliminates Odor-Causing Germs

Germs and bacteria are not the only problems you have to deal with when cleaning the air. A bad smell can bother you even if there is no contamination by germs or pathogens. The use of ultraviolet light helps eliminate odors, especially those associated with cooking or pets.

3. Improve the quality of air and more comfort at home

An ultraviolet bulb will help improve the quality of indoor air. Actually, it works just like a photocatalytic filter with an oxidizing effect on impurities present in the atmosphere. You can breathe fresher and healthier air.

The quality of air in your home can be improved by filtering out different pollutants. According to the EPA, indoor air pollution is one of the five most dangerous types of pollution. You are inhaling many harmful substances from cooking, smoking, bathrooms, pets, and other activities.

The UV-C light filter in an air purifier provides a germicidal cleaning to remove these impurities from the air. Therefore it eliminates all odors caused by bacteria or chemicals found indoors. This way you will have fresher and cleaner air in your house.

4. UV-C Filters Promote Better Health

Ultraviolet filters used in an air purifier can help you stay healthy by offering a cleaner and fresher breathing environment. In addition, people living in these houses were more likely to suffer from allergies, asthma, or other respiratory diseases. So, using a UV-C filter will allow you to have a healthier home without pollutants that harm your health.

In conclusion, having clean indoor air is one of the most effective ways to prevent disease caused by poor air quality.

Disadvantages of UV-V light filter

There are some disadvantages of using UV-C technology for purifying the indoor environment.

1) Required frequent filter changes

Effectiveness of the artificial UV light decreases once it shines through dust particles and loses its ability to kill bacteria and viruses. So, the air cleaner needs to be changed every six months. This factor makes air purifiers expensive maintenance-wise.

Additionally, if you do not change the filter frequently, then the pollutants will accumulate inside your home. These pollutants cause health risks like respiratory problems, allergy attacks, etc. Therefore, it is important you clean your UV lights regularly so that they can purify the air effectively.

2) Not an effective for particulate removal

Artificial ultraviolet light does not effectively remove particles in your homes like dust, and mold. Because these types of pollutants are larger than bacteria and viruses. Therefore, if you want to keep your indoor environment free from large particles, UV-C technology is not a good choice. It can only remove pollutants invisible to our naked eye, including bacteria and viruses only.

UV-C lights also contain mercury vapors which could prove hazardous for health as well as the environment. Although most companies claim that their filters are made of quartz, there are still chances that the lamp globe may break during replacement. This could cause you to inhale harmful mercury vapors.

3) Not helpful in mold removal

Ultraviolet light cannot kill mold spores because these spores are larger than bacteria and viruses. Reduction in humidity level also does not affect these air purifiers for removing spores effectively from the indoor environment. It can only help remove musty odors caused by molds, but it cannot completely eradicate them from your home.

Thus, using a HEPA filter is recommended over a UV light filter air purifier for molds. They do not pose any health hazards associated with mercury vapors, nor do they frequently require filter changes.


We hope this blog post has helped you understand the benefits of UV-C light filters and how they can benefit. If it’s time to replace or upgrade your filter, we recommend contacting a professional who is trained in installing these products for safety reasons.