Introduction to AP-UVGI: The innovative technology that uses human-safe Far-UVC light

Introduction to AP-UVGI

AP-UVGI, or Active Personnel Ultraviolet Germicidal Irradiation, is a new and innovative technology that uses human-safe Far-UVC shortwave irradiation to replace conventional longer wavelength UVGI and UR-UVGI germicidal ultraviolet-c irradiation. This technology is considered to be the most disruptive non-pharmaceutical pandemic countermeasure in human history.

The History of AP-UVGI

The first germicidal research into excimer lamps, which generate Far-UVC radiation, were developed in 1982 at the State Optical Institute in Leningrad. The Far-UVC radiation from these lamps is triggered by a barrier discharge generated with a high-frequency generator. Noble gas molecule emissions provide the peak wavelengths necessary for AP-UVGI, which are found to be human-safe at 222nm wavelengths in the narrow part of the electromagnetic spectrum referred to as Far-UVC.

The Discovery of AP-UVGI

Over the last two decades, people from all over the world have collaborated to find the sweet spot for AP-UVGI. The first breakthrough study into the effect of radiation from KrCl 222nm and KrBr, 207nm excimer lamps on microorganisms and chemical particles began in 2000 at Tomsk State University. It was found that these lamps are a very effective system for carrying out ultraviolet inactivation of viruses, bacteria, and pathogens.

Safety Confirmation of AP-UVGI Wavelengths

Dr. David Brenner, who directs the Center for Radiological Research at Columbia University, Irving Medical Center in New York City, has been leading the charge for the use of Far-UVC irradiation excimer lamps. Over the past eight years, he and his team have been developing the use of these lamps to neutralize bacteria, bacterial fragments, molds, yeasts, and viruses, including SARS-CoV-2. Dr. Brenner has personally approved filtered versions of excimer lamps emitting between 207nm and 222nm light as safe for deployment in spaces occupied by active personnel undergoing the UVGI decontamination process.

A study published in September 2020 in the American Journal of Infection Control by researchers at Hiroshima University found that 222nm UV excimer lamps eliminate 99.7% of surface contamination by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19.

Conclusion

AP-UVGI, or Active Personnel Ultraviolet Germicidal Irradiation, is a new and innovative technology that uses human-safe Far-UVC shortwave irradiation to replace conventional longer wavelength UVGI and UR-UVGI germicidal ultraviolet-c irradiation. This technology has been developed over the last two decades with collaboration from people all over the world, and has been approved as safe for deployment in spaces occupied by active personnel undergoing the UVGI decontamination process. Further research is needed to fully understand the potential of AP-UVGI in reducing the spread of viruses, including SARS-CoV-2.

Far-UVC light is a type of ultraviolet (UV) light with a wavelength range of 207-222 nm. It has been shown to be as effective as conventional germicidal UV light in killing microorganisms, but without the associated human health risks because it has a limited penetration depth in biological materials. Far-UVC light is absorbed by proteins and other biomolecules, so it cannot reach living human cells in the skin or eyes, but it can still penetrate and kill viruses and bacteria. A study conducted by researchers at Columbia University Irving Medical Center demonstrated that low doses of far-UVC light (222 nm) efficiently inactivated airborne human coronaviruses alpha HCoV-229E and beta HCoV-OC43. Continuous exposure to far-UVC light at the current regulatory exposure limit could result in a significant reduction in the ambient level of airborne coronaviruses in occupied public locations while staying within the current regulatory dose limits.

 

Columbia University Irving Medical Center explored the efficacy.

This study conducted by researchers at Columbia University Irving Medical Center explored the efficacy of far-UVC light (222 nm) against two airborne human coronaviruses: alpha HCoV-229E and beta HCoV-OC43. The results showed that low doses of far-UVC light were highly efficient in inactivating these viruses when exposed in aerosol droplets similar in size to those generated during sneezing and coughing. The inactivation rate constant for the alpha coronavirus HCoV-229E was 4.1 cm2/mJ and for the beta coronavirus HCoV-OC43 was 5.9 cm2/mJ. The results also showed that exposure to far-UVC light reduced the expression of the viral spike glycoprotein, indicating a reduction in the number of infected cells. The study concludes that far-UVC light has the potential to be used in occupied public settings to prevent the airborne person-to-person transmission of pathogens such as coronaviruses.

The study reports on the potential use of far-UVC light at 222 nm to inactivate airborne viruses, including human coronaviruses, without causing biological damage in human cells and tissue. The approach is based on the principle that far-UVC light can penetrate and kill viruses and bacteria, which are typically micrometer dimensions or smaller, but it cannot penetrate human skin or the outer tear layer on the surface of the eye. The study found that low doses of far-UVC light at 222 nm efficiently killed airborne human coronaviruses carried by aerosols. The inactivation rate was estimated to be 1.2 to 1.7 mJ/cm2 of 222-nm light to inactivate 99.9% of the airborne human coronavirus tested. The study suggests that the use of far-UVC light may be a safe and inexpensive tool to reduce the spread of airborne-mediated viruses in public places like hospitals, transportation vehicles, restaurants, airports, and schools. However, it is important to note that more research is needed to fully understand the potential of far-UVC light in reducing the spread of viruses, including SARS-CoV-2.

This study describes the effect of far-UVC light (222 nm) on aerosolized coronaviruses. The far-UVC light was generated by a 12 W 222-nm KrCl excimer lamp and was directed at the UV exposure chamber, which was positioned 22 cm away from the lamp. The relative humidity, temperature, and particle size distribution were monitored throughout the experiment, and the particle size distribution was found to be 83% between 0.3 μm and 0.5 μm, 12% between 0.5 μm and 0.7 μm, and 5% >0.7 μm. The exposure intensity was measured to be approximately 90 μW/cm2, and the exposure dose to a particle was calculated to be 2 mJ/cm2. The far-UVC dose delivered to aerosol particles was varied by inserting additional UV-transparent plastic films, resulting in three test doses of 0.5, 1.0, and 2.0 mJ/cm2. The virus infectivity was determined using the 50% tissue culture infectious dose (TCID50) assay, and the virus survival was analyzed using robust linear regression with iterated re-weighted least squares. The virus inactivation cross section, D90, which is the UV dose that inactivates 90% of the exposed virus, was calculated based on the regression results. The study showed that far-UVC light was effective in inactivating aerosolized coronaviruses, and that the inactivation rate increased with increasing doses of far-UVC light.

FAQs

1. What is Far-UVC Light? Far-UVC light is a type of ultraviolet (UV) light with a wavelength range of 207-222 nm. It has been shown to be as effective as conventional germicidal UV light in killing microorganisms, but without the associated human health risks.
2. Is Far-UVC Light Safe for Humans? Yes, Far-UVC light is safe for humans because it has a limited penetration depth in biological materials. It is absorbed by proteins and other biomolecules, so it cannot reach living human cells in the skin or eyes.
3. What is the Efficacy of Far-UVC Light in Killing Airborne Coronaviruses? A study conducted by researchers at Columbia University Irving Medical Center showed that low doses of far-UVC light (222 nm) were highly efficient in inactivating airborne human coronaviruses. The inactivation rate was estimated to be 1.2 to 1.7 mJ/cm2 of 222-nm light to inactivate 99.9% of the airborne human coronavirus tested.
4. What are the Potential Uses of Far-UVC Light? The study suggests that the use of far-UVC light may be a safe and inexpensive tool to reduce the spread of airborne-mediated viruses in public places like hospitals, transportation vehicles, restaurants, airports, and schools. However, more research is needed to fully understand the potential of Far-UVC light in reducing the spread of viruses, including SARS-CoV-2.

FAQ Conclusion

Far-UVC light is a safe and effective solution for killing airborne coronaviruses. It has been shown to be as effective as conventional germicidal UV light in killing microorganisms, but without the associated human health risks. The use of Far-UVC light may be a valuable tool in reducing the spread of airborne-mediated viruses in public places, but further research is needed to fully understand its potential.