How To Air Purifier Kills COVID-19 in The Air?

A COVID-19 epidemic has severely affected people's work and life rhythm, and has resumed the outbreak of daily health protection! In addition to the protection of outdoor spaces, the indoor environment of the workplace also needs to be highly valued. Because in central air-conditioning or inconveniently ventilated confined spaces, the spread and retention of the virus are indoors. It is used as an indoor "line of defense". "—Can the air channel effectively filter viruses? Cold catalyst air purifiers have become one of the focuses of public attention.

In response to the problem, Mr. Daizizhu, an environmental and health expert from the Institute of Environmental and Health-Related Product Safety of the China Center for Disease Control, said: During the epidemic, in addition to enhancing ventilation, HEPA filters of H12 and above should also be used. Use it as an air filter to clean the air with virus-laden aerosols and droplets.

Reprint articles: Dr. Ahmad Sedaghat, MD, director of the University of California Department of Medicine, said that several published studies have evaluated aerosols and submicron particles similar in size to SARS-CoV-2 virus particles, and the results show that portable HEPA purifiers can significantly reduce air COVID-19 particles. The results of this study can be applied to our daily lives outside the doctor’s office," Sedaghat said. "If you want to host a larger party, you should consider putting an air purifier in your home living room to help purify Anything released into the air. HEPA-based air purifiers work best. HEPA-based air purifiers can purify these air particles faster and more efficiently than non-HEPA filters.

HEPA is the abbreviation of High Efficiency Particulate Air Filter in English, and the Chinese translation is "High Efficiency Particulate Air Filter". The HEPA filter is the heart of the air purifier. It is used to filter PM2.5. It can adsorb formaldehyde, filter bacteria and viruses. Some HEPAs also come with activated carbon, which can have a certain sterilization effect. However, the HEPA filter cannot completely eliminate bacteria and viruses, so the main function of the air purifier is to purify the air, eliminate peculiar smells and eliminate harmful gases. HEPA can be subdivided into H10, H11, H12, H13, and H14 according to specifications. HEPAs of these specifications are all high-efficiency filters. The HEPA12 grade mentioned by Dai Zizhu in the video is a high-efficiency filter that filters aerosols and droplets in the air to prevent the spread of the new coronavirus in the air in a closed environment. The higher the HEPA grade, the higher the disposable filtration rate. Of course, the higher the level, the greater the wind resistance and the greater the noise. In addition to HEPA, what are the sterilization and antivirus?

Is there ultraviolet light that can sterilize and detoxify?

Ultraviolet rays with a wavelength of 240-270nm can break the ability of DNA to produce proteins and replicate. When the DNA and RNA of bacteria and viruses are damaged, their ability to produce proteins and their ability to reproduce will be lost. Because bacteria and viruses generally have a short life cycle, bacteria that cannot reproduce, the virus will die quickly.

So what kind of air purifier can be considered as high standard can be judged from the following three points:

First of all, is there any third-party authority testing and certification for virus removal capabilities?

Recently, there have been reports that “the air purifier product standard does not have a requirement for virus killing rate, and it may not be suitable for filtering viruses.” This also strongly reminds us that since the product has not formulated this standard, it should be passed. Authoritative testing by tripartite agencies, after actual testing, can effectively filter out the air purifier is worth choosing. The classification mechanism of the HEPA filter is diversified. Many product manuals or e-commerce pages do not indicate the diameter range that can filter the pollution source, and even if it is indicated, it is only a theoretical value. Therefore, it is more credible to obtain the inspection and certification of a third-party authority.

Second, see if the HEPA filter element level of the air purifier reaches H12 or above?

Some air purifier products on the market are equipped with HEPA filters, which are interwoven with very fine organic fibers, which have a strong ability to capture particles (including aerosols), small pores, and high purification efficiency. Of course, the HEPA filter also has a detailed classification, and different levels have different filtration efficiencies for particles of different diameters.

The authoritative testing agency has confirmed that air purifiers with MERV16 or H12 and above and with antibacterial coating and high-efficiency HEPA filter elements can filter out H1N1 viruses up to 99.99%. The reason why air cleaning has such a high removal rate of viruses is because it intercepts most aerosols and droplets, making the virus unable to escape.

According to the information released by the Chinese Center for Disease Control and Prevention of Viral Diseases: The size of the new coronavirus is about 100 nanometers, which is similar to the size of the H1N1 virus (the size of the H1N1 virus is 80-120 nanometers), and the two are also attached to aerosols or in the air. Droplets are present.

In view of the similar diameter and the shared transmission route, if the air purifier is equipped with a high-efficiency HEPA filter element of MERV16 or H12 and above with an antibacterial coating, it can effectively filter out the H1N1 virus by 99.99% in a confined space through circulating purification. For viruses of approximately H1N1 size, and viruses carried on aerosols, it should also be filterable.

Third, see if the HEPA filter element has an antibacterial coating?

Pure physical filtration will have the risk of secondary pollution caused by residual pollutants. The high-efficiency HEPA filter with an antibacterial coating can ensure the effective inhibition of the breeding and reproduction of microorganisms, avoid secondary pollution, and achieve close to zero emissions of particulate matter at the air outlet.

At the moment of the epidemic, prevention is indispensable, but if you want to establish a "city wall" defense line to prevent the virus indoors, then equipped with a high-standard air purifier that has been tested and certified to filter out the virus, it is the indoor protection of the epidemic. One of the important means.