Home » Blogs » Do Air Purifiers with UV Light Really Work? How To Use Them Correctly?

Do Air Purifiers with UV Light Really Work? How To Use Them Correctly?

Views: 0 Author: Site Editor Publish Time: 2025-01-09 Origin: Site

Inquire

Air purifiers with ultraviolet light function are effective in cleaning the air, but they also have some limitations.

1. Principle and effectiveness of ultraviolet disinfection

Sterilization principle

Ultraviolet (UV) light is a type of electromagnetic wave, among which ultraviolet C (UVC) light with a wavelength between 200 - 280nm has a strong bactericidal ability. When microorganisms (such as bacteria, viruses, mold, etc.) are exposed to UVC ultraviolet radiation, the ultraviolet rays will destroy the DNA or RNA structure of the microorganisms. Specifically, the energy of ultraviolet photons is absorbed by the nucleic acids of microorganisms, breaking the chemical bonds in the nucleic acid molecules and forming pyrimidine dimers, thereby interfering with the transmission and replication of genetic information of the microorganisms, causing the microorganisms to be unable to reproduce and survive normally, and ultimately die.

Purification effect on air microorganisms

In air purifiers, the ultraviolet irradiation area can effectively kill bacteria and viruses in the air. For example, for common bacteria such as Staphylococcus aureus and Escherichia coli, as well as some viruses such as influenza virus, after sufficient doses of ultraviolet radiation, their activity and quantity in the air can be significantly reduced. Studies have shown that under appropriate ultraviolet intensity and exposure time, the killing rate of these microorganisms can reach more than 90%, thereby reducing the threat of harmful microorganisms in the air to human health, especially for people with weak immunity, such as the elderly, Children and patients can reduce the risk of illness from airborne microbial infections.

2. Limitations of UV Air Purifiers

Limited UV exposure range

The air flows quickly in the purifier and the irradiation range of the ultraviolet lamp is limited. If the air is not adequately exposed to the UV irradiation area, the microorganisms in it cannot be effectively killed. Moreover, the intensity of ultraviolet light will weaken with increasing distance, so only microorganisms within a certain distance around the ultraviolet lamp can be irradiated with sufficient intensity. This requires that the air flow design inside the air purifier be reasonable to ensure that the air can fully pass through the ultraviolet irradiation area, but in actual design, it is difficult to ensure that all air entering the purifier can be completely treated by ultraviolet rays.

Not effective against other pollutants

Ultraviolet rays mainly have a bactericidal and disinfecting effect on microorganisms, and are not very effective in removing other pollutants in the air, such as dust, pollen, smoke particles, formaldehyde and other chemical pollutants. These pollutants need to be filtered and adsorbed by other filtering components of the air purifier, such as the primary filter, HEPA filter and activated carbon filter. For example, ultraviolet rays cannot decompose formaldehyde molecules or absorb dust particles, so they cannot replace traditional air purification technology to deal with these non-microbial pollutants.

May produce harmful byproducts such as ozone

Ozone may be produced when ultraviolet light strikes oxygen in the air. Ozone is a strong oxidant that can irritate and damage the human respiratory tract, eyes, etc. at high concentrations. Although some high-end UV air purifiers take measures to control ozone production, such as using special UV lamps and catalysts to break down ozone, the amount of ozone produced may increase if the equipment is not of good quality or is used for a long time. This has a negative impact on indoor air quality.

Air purifiers with ultraviolet light are effective in killing microorganisms in cleaning the air, but you cannot rely solely on ultraviolet light to purify the air. It needs to be combined with other air purification technologies and pay attention to the harmful byproducts it may produce.

微信图片_20241211095227

How to use an air purifier with ultraviolet light correctly?

The correct use of air purifiers with ultraviolet rays is essential to its purification function and safety. Here are some key points:

1. Installation location selection

Avoid direct contact with ultraviolet rays

Since ultraviolet rays are harmful to human skin and eyes, the air purifier should be placed outside the activity area. Do not place it next to the bed, sofa, or other places where people stay for a long time. It is best to place it in a corner or against the wall so that ultraviolet radiation will not directly irradiate the human body. For example, when using it in the bedroom, it can be placed in a corner away from the head of the bed to ensure that it will not be affected by ultraviolet rays when sleeping.

Ensure good air circulation

Choose a well-ventilated location so that air can enter the purifier more smoothly for processing. Avoid placing it in a small closed space or a location blocked by furniture and other items to prevent air from fully entering the purifier. For example, do not place the air purifier behind a large wardrobe or next to a curtain. There should be enough space for air to enter the purifier from all directions.

2. Check before use

Check whether the ultraviolet lamp is working properly

Check whether the ultraviolet lamp is on when using it for the first time and during regular inspections. Some air purifiers have an ultraviolet lamp working indicator light, which can be judged by observing the indicator light. If there is no indicator light, you can turn on the purifier in a dark environment and observe whether there is a weak ultraviolet light (be careful not to look directly at the ultraviolet lamp). At the same time, check whether the ultraviolet lamp has signs of damage or aging, such as whether there are black spots or cracks on the surface of the lamp tube. If any problems are found, the lamp tube should be replaced in time.

Check the sealing of the equipment

Make sure that the shell of the air purifier is well sealed. If the equipment is poorly sealed, air may bypass the ultraviolet irradiation area and flow directly out of the gap, thereby reducing the purification effect. You can check the sealing by feeling whether there is obvious air leakage around the purifier, or you can check the manual of the equipment to understand its sealing design requirements and inspection methods.

3. Precautions during use

Set the working mode according to the manual

Different air purifiers have different working modes, including wind speed adjustment, ultraviolet light switch (if it can be controlled separately), etc. Set the appropriate mode according to actual needs. For example, when the air quality is good, you can choose a lower wind speed and turn on the ultraviolet lamp intermittently; when the air pollution is serious or there are many people indoors, choose a higher wind speed and keep the ultraviolet lamp on to enhance the purification effect.

Pay attention to ozone production

Pay attention to whether the equipment produces ozone. Some air purifiers with ultraviolet light may produce a small amount of ozone during operation, which may be harmful to human health. If you smell ozone gas similar to fishy smell or burnt electrical appliances, you should stop using it immediately and check whether the equipment is normal or contact the manufacturer for repair. Some high-end air purifiers have ozone monitoring and decomposition functions. If there is such a function, make sure it works properly.

Regular cleaning and maintenance

Clean the filter regularly. Although ultraviolet light is mainly used for sterilization, the cleaning of the filter is also important for the overall purification effect. According to the use environment and the recommendations of the manual, regularly clean or replace the primary filter, HEPA filter and activated carbon filter, etc. For ultraviolet lamps, the surface of the lamp should also be cleaned regularly to prevent the accumulation of impurities such as dust from affecting the transmittance and sterilization effect of ultraviolet light.

4. Use time control

Avoid long-term continuous use of the ultraviolet function

Unnecessary long-term continuous use of the ultraviolet function may increase the risk of ozone generation and accelerate the aging of ultraviolet lamps. The use time of ultraviolet lamps can be reasonably controlled according to the activities of indoor personnel and air quality. For example, when there is no one in the room, the ultraviolet lamp can be turned on for air disinfection; when there are people in the room, the ultraviolet lamp can be turned on intermittently or the power can be reduced (if the device supports it).