Ultraviolet disinfection ＂new crown＂, how long does it take to be effective?
发布时间：2021-11-23 11:04
来源：萤光创新
COVID-19's pandemic clearly shows that globalization in recent years has a huge impact on the prevalence of infectious diseases. Medical institutions are undoubtedly the forefront of Xinguan prevention and control and the "position" facing the greatest risk. How to do a good job in prevention and control in medical institutions and create a relatively safe environment for medical personnel and inpatients is undoubtedly the most important. The safe environment needs to be realized by disinfection. In the new crown guideline and various literature reports, it is clearly pointed out that COVID-19 is sensitive to ultraviolet radiation. How long will it take to kill COVID-19 effectively? Is it half an hour? 1 hour?
Ultraviolet light mainly acts on the DNA of microorganisms. By destroying the DNA structure, it loses the function of reproduction and self replication. It can also ionize the oxygen in the air to produce ozone with bactericidal effect, so as to achieve the purpose of disinfection. Ultraviolet light can kill common pathogens such as viruses, bacteria and fungi. Ultraviolet disinfection is a cost-effective disinfection option! How long time will it take to kill COVID-19 if the ultraviolet lamp is used for disinfection of the new crown?
Researchers have done some research on the time of UV killing the new crown and the ultraviolet lamp has been used to irradiate COVID-19 samples. As shown in the following picture, all the COVID-19 can be killed by mixing the ultraviolet rays of two bands (UVA+UVC) for 9 minutes. 50% of the viruses can be inactivated after 1.4 minutes of mixed ultraviolet irradiation of the two bands. UVA exposure alone had a poor effect on virus inactivation. After 9 minutes of irradiation, the emission dose was 292 MJ / cm2, and a log reduction in virus load was observed. In contrast, the virus was completely inactivated after exposure to UVC for 9 minutes and the emitted UVC dose was 1048 MJ / cm2. These data confirm the previous findings that UVC is more effective in inactivating viruses, and emphasize that UVC radiation is an effective method to inactivate new crowns.
Classification of ultraviolet rays (UVA and UVC)
UVA band, with a wavelength of 320 ~ 400nm, is also known as long wave black spot effect ultraviolet. It has strong penetration and can penetrate most transparent glass and plastics. More than 98% of the long wave ultraviolet contained in sunlight can penetrate the ozone layer and clouds to the earth's surface. UVA can directly reach the dermis of the skin, destroy elastic fibers and collagen fibers, and Tan our skin.
UVC band, with a wavelength of 200 ~ 285nm, also known as short wave sterilized ultraviolet. It has the weakest penetration ability and cannot penetrate most transparent glass and plastics. The short wave ultraviolet contained in sunlight is almost completely absorbed by the ozone layer. Short wave ultraviolet radiation does great harm to human body. Short time irradiation can burn skin, and long-term or high-intensity irradiation can also cause skin cancer. The ultraviolet sterilization lamp emits UVC short wave ultraviolet.
UV energy MJ / cm2 = unit time s × UV intensity UW / cm2 * 103. 1mJ/cm2=1000 uJ/cm2=1000 uw/cm2 × 1s
Studies have shown that ultraviolet lamps can effectively kill COVID-19 (even though the virus concentration is relatively high), and the time required is relatively short. It can be used in medical institutions, even in the new crown Hospital of new crown disinfection, generally ten minutes.
Of course, ultraviolet disinfection also has many shortcomings. For example, it can not be used when there are personnel. Ultraviolet radiation will destroy the DNA in cells and cause damage to human body. In light cases, it will cause redness, swelling and itching, and in severe cases, it will even cause skin cancer. Its penetration ability is weak and can only be used for surface disinfection. But recently, many experts also pointed out that the new crown can be transmitted from thing to person. In fact, for the disinfection of object surface, it is OK to choose ultraviolet irradiation for 10 minutes.
Qingdao fluorescent Innovation Technology Co., Ltd. has a professional postdoctoral team, focusing on the research of ultraviolet sterilization application. After years of deep cultivation in the ultraviolet industry, the company has obtained a number of national invention and utility model patents. At present, a number of sterilization module products have been put into the market. For more details, you can browse the company website www.qdyingguang.com, contact the company for WeChat's official account.
Keywords: UVC, UVC led, deep ultraviolet, ultraviolet sterilization, ultraviolet disinfection, deep ultraviolet LED, water sterilization, water disinfection, air sterilization, air purification, flowing water sterilization, static water sterilization
