The ultraviolet ray with a wavelength greater than the medium ultraviolet ray is called far ultraviolet ray. According to the definition of CIE, the UV-C wavelength range is 100-280nm. C-band ultraviolet lamp is commonly known as ultraviolet germicidal lamp. UVC germicidal lamp is a low pressure mercury lamp. It emits ultraviolet light by using the low mercury vapor pressure (<10-2 Pa) to be excited. There are two main emission spectral lines: one is 253.7 nm wavelength; The other is 185 nm wavelength, both of which are invisible C-band ultraviolet rays.
Ultraviolet disinfection technology has incomparable germicidal efficiency with other technologies, and the germicidal efficiency can reach 99% – 99.9%. However, it usually takes 20 minutes to 1 hour for traditional chemical disinfection methods such as chlorine and ozone to achieve sterilization effect.
UVC germicidal lamp does not need to be converted into visible light. The wavelength of 253.7 nm can play a very good role in germicidal efficacy. This is because there is a rule for the absorption spectral line of light waves by cells. Ultraviolet rays at 250-270 nm have the maximum absorption. The absorbed ultraviolet rays actually act on the genetic material of cells, namely DNA. It plays a photochemical role. The energy of ultraviolet photons is absorbed by the base pairs in DNA, causing genetic material to change, The bacteria will die immediately or cannot reproduce, so as to achieve the purpose of sterilization.
Ultraviolet germicidal lamp is generally used to sterilize air, object surface and water. 253.7 nm wavelength can effectively kill bacteria and viruses, which has been studied for a long time. Ultraviolet sterilization is characterized by broad-spectrum. Some viruses that are difficult to kill at high temperatures can be quickly killed by ultraviolet. This is because the ultraviolet sterilization mechanism is different from other methods.
Sterilization: the water molecules in the air and the surface treated by photocatalyst, through the catalysis of ultraviolet light, produce oxidation, and decompose the bacteria in the air.
Deodorization: The daily odor sources are mainly ammonia, hydrogen sulfide, methyl mercaptan, acetaldehyde, etc. Photocatalyst has more oxidation capacity than ozone and negative ions. These odor sources can produce photocatalyst oxidation in the presence of photocatalyst by using fluorescent light to decompose the odor source.
Odor removal: It can generate a large amount of ultraviolet light speed to irradiate the odor gas, degrade and transform the odor gas into low molecular compounds [UV+O ∈→ O -+O * (active oxygen) O+O ∈→ O ∈ (ozone)], such as CO ∈, H ∈ O and other harmless gases, so as to achieve effective odor removal effect without secondary pollution.