Eliminate 99.9% of the coronavirus, American research shows it can be done through ultraviolet light.

Author: Lin Yixuan

As of July 5, at least 527,241 people worldwide have died from COVID-19, with at least 11,145,640 confirmed cases. A team from the United States recently pointed out that under specific wavelengths of ultraviolet light, over 99% of airborne droplets containing seasonal coronaviruses can be killed, and it is harmless to humans.

This research was conducted by the Irving Medical Center at Columbia University. The team pointed out that far ultraviolet light at a wavelength of 222 nm can safely kill airborne influenza viruses. Since the COVID-19 virus belongs to the coronavirus family, the results are expected to extrapolate to the prevention of COVID-19.

Ultraviolet light has long been used to kill bacteria, viruses, and molds

In fact, UV disinfection has been practiced for many years, with UVC lamps (wavelength 254 nm) commonly used to kill bacteria, viruses, and molds, particularly in hospitals and the food processing industry. However, UVC is very dangerous, potentially causing skin cancer and eye problems, and can only be used in unoccupied areas. Additionally, the New York subway system plans to use ultraviolet lamps to disinfect trains, but only during the night when trains are out of service. Researchers at Columbia University have spent years studying improvements and applications of such UV light, and the pandemic has coincidentally validated the value of their experiments. Team leader David Brenner noted in May that far ultraviolet light at 222 nm, slightly shorter than the previously used UVC lamp wavelengths, is harmless to humans, unable to penetrate the skin or the surface of the eyes, but can kill viruses. This means that far ultraviolet light will not cause damage to exposed human tissue and cannot reach or harm living cells inside the body. This represents a promising application of far UV light in high-risk, crowded spaces during the current pandemic.

ultraviolet light

Slightly shorter wavelengths of far ultraviolet light are harmless to the human body

Foreign media report that to simulate the situation of airborne droplets carrying viruses, the team used a nebulizer to aerosolize two common coronaviruses and then exposed them to far ultraviolet light, subsequently examining how many of the viruses remained alive. The researchers also calculated that continuous exposure to far UV light for about 8 minutes can kill 90% of airborne viruses; approximately 11 minutes can kill 95%; about 16 minutes can kill 99%; and about 25 minutes can kill 99.9% of the airborne pathogens. Since coronaviruses that infect humans have similar genomic sizes, David Brenner believes that far ultraviolet light is likely to have a similar effect on the COVID-19 virus. Low-dose far UV exposure is expected to significantly reduce coronaviruses in public spaces in the future.

ultraviolet light.

Reference: Far-UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses

Article reprinted from: https://heho.com.tw/archives/89765