Is there any good method for indoor disinfection?
Speaking of disinfection, our traditional disinfection methods include high-temperature steam disinfection, mercury lamp disinfection, boiling water disinfection, and alcohol disinfection ... But all of the above methods have their drawbacks. They can no longer fully meet the needs of modern people. What we need is a Healthy, environmentally friendly and efficient disinfection method, the new technology introduced below is LED ultraviolet disinfection.
The bactericidal effect of sunlight is actually light with a wavelength between 200 and 275 nanometers (nm), which belongs to UVC. It can penetrate biological cell membranes and nucleus, destroy DNA (or RNA molecular structure in microbial body cells, destroy DNA, cause growth cell death and / or regenerative cell death, and play the role of killing various germs Unlike the ultraviolet light produced by mercury lamps, the ultraviolet light produced by LEDs does not produce ozone, uses mercury as a medium, does not produce secondary pollution, does not add any chemicals, is a physical disinfection method, and is a green and healthy disinfection .
We often hear the words "Have more sun, sterilization!" Is this true? Really. But it is not the legendary ultraviolet rays that actually sterilize in sunlight, but infrared rays with heating effects. In other words, the heat caused by sunlight kills viruses and bacteria. It is not difficult to understand that SARS, which raged 17 years ago, arrived Summer suddenly disappeared because the SARS virus is sensitive to temperature!
So don't expect to kill the virus in the sun this season!
So does ultraviolet light have the function of disinfection and sterilization? Yes, but only UVC has this skill. As shown in the figure, ultraviolet rays can be divided into UVA, UVB and UVC according to wavelength. Among them, the penetration ability of UVA penetrates. Most of the ultraviolet rays received on the ground are UVA, and a small part are UVB with weak penetration ability. The UVC in the sun is absorbed in the ozone layer and cannot reach the ground, so it is customary The solar radiation of 200 ~ 280nm can't reach the mid-UV spectrum of the earth.
The relationship between the survival amount of SARS virus and the exposure time under UVA and UVC irradiation. UVA has almost no inactivation effect on SARS coronavirus. However, under the irradiation of deep ultraviolet light with a characteristic wavelength of 254 nm and a radiation intensity of 4016 μW / cm², the virus kill rate LOG The value has a linear relationship with the dose (time).
Irradiation of microorganisms such as bacteria and viruses by UVC will destroy the molecular structure of DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) in the cells of the microorganism, causing DNA strand breaks, cross-linking and breaking of nucleic acids and proteins, and causing growing cells Death and regenerative cell death, to achieve the effect of sterilization and disinfection.
UVC belongs to a broad-spectrum bactericidal class, which can kill all microorganisms, including bacteria, tuberculosis, viruses, spores and fungi, but the dosage required for different killing objects is different.