The collaboration between NIST and DHS revealed which wavelengths of UV work best disinfect the COVID-19 virus. To disinfect a surface, you can illuminate it with ultraviolet light (UV), a wavelength bluer than the human eye can see. But to specifically inactivate SARS-CoV-2 (the virus that causes COVID-19), which wavelength is the best light? And how much radiation is it enough?The SARS-CoV-2 viruses are susceptible to UV light at the same wavelength as other viruses, such as those that cause influenza. The most effective wavelength is that in the "UVC" range between 222 and 280 nm (nm). The UVC light (full range from 200 to 280 nm) is shorter than the resulting sunburn UVB wavelength (280 to 315 nm).

The scientists have also shown that the surrounding environment can protect the virus. In experiments, the virus is administered at less required UV doses in pure water than in simulated saliva, which contains salt, proteins, and other substances in actual human saliva. Levitating the virus in simulated saliva creates a real-world scenario similar to that involving sneezing and coughing. This detail may make the findings more directly informative than in previous studies.

"I think a big contribution of this study is that we are able to show that the idealized results we see in most studies don't always predict what happens in more realistic situations," said Michael Schuit of NBACC. This may reduce the efficacy of UV purification methods when you have substances like simulated saliva around a virus."

Manufacturers and regulators of UV disinfection devices can use these results to help understand how long healthcare, vehicles and even liquid surfaces should be irradiated to achieve inactivation of the SARS-CoV-2 virus.

Although the UV disinfection capacity has been known for more than a hundred years, UV disinfection research has seen an explosive growth over the last decade. One reason is that traditional UV light sources sometimes contain toxic substances, such as mercury. Recently, the use of non-toxic LED lights as a UV light source has mitigated some of these concerns.

LEDESTAR specializes in SMD LED more than 10 years, has always been adhering to the technology to create value, and constantly increase research and development, in the case of increasing uv demand, our uv LED is also familiar to more people, many models including 2835, 3030, 3535, 6868, applied in daily life sterilization, hospital sterilization and other fields.

UVA applications

• In line with the photon reaction curve of insects, insect trap led light and mosquito control led light can be made.(365nm-400nm)
• UVA is the central area of plant photon, which can stimulate anthocyanin for led grow light and horticulture lighting. (390nm-400nm)
• Under UVA, the phosphor can be recognized and it is widely used in gem identification.(365nm-370nm)
• UVA can stimulate the photon catalyst, produce strong oxidation substances, function on sterilization and deodorization. (365nm-400nm)
• The UVA is available for UV curing and UV 3D printing.Curing applications include UV glue curing in display screen, electronic medical treatment, instrument and other industries, and UV ink curing in building materials, furniture, home appliances, automobile and other industries.And PCB industry UVA curing such as components (capacitance, various plug-ins, screws, chips, etc.) fixed, moisture-proof sealing and core circuit, chip protection, antioxidant coating protection.

UVB applications

• UVB has spiloplaxia effect toward human body, it can promote the formation of mineral metabolism and vitamin D in the body, can be used for skin detection, and has a significant effect on psoriasis and other skin diseases treatment.
• UVB can also detect and identify special materials such as proteins, phosphor medicine, fluorescent paint, food additives and other special materials.
• UVB can accelerates the production of plant polyphenols and other active substances, it is useful for led grow light.

UVC applications

• UVC kills all microorganisms by destroy the DNA, including bacteria, tuberculosis, viruses, spores, and fungi, but different sanitizers require different doses.
• UVC is widely used in hospitals, air conditioning systems, disinfection cabinets, water treatment equipment, water fountains, sewage treatment factory, swimming pools etc.