Oh, patents! – UV light sanitizing technology redux (1)

Copyright © Françoise Herrmann

Renewed interest exists in the use of UV (Ultra-Violet) light sanitizing technology, within the context of the COVID 19 pandemic (e.g., Cantor, 2020; Martin, 2020; IUVA Fact sheet 2020).

What is UV light sanitizing technology?

UV (Ultra Violet) light sanitizing technology, sometimes called UVC or Far-UVC light sanitizing technology, has been used for more than 40 years to remove human pathogens such as bacteria, viruses, fungi and algae from drinking water, wastewater, air, food products and various surfaces. UV light sanitizing technology is able to remove pathogens because exposure actually damages the nucleic acids of micro-organisms (Trojan UV; Rammelsberg, 1998). In other words, when the high energy of short UVC wavelengths is absorbed by cellular RNA and DNA,  it creates new double bonds called dimers, particularly Thymine dimers, which then prevent the micro-organisms (e.g., bacteria or viruses) from replicating, and thus from infecting other cells. This known neutralizing effect on the RNA and DNA of pathogens is precisely what is stoking renewed interest in UV light sanitizing technology, in the war against  the SARS-Corona virus 2. A virus that has now infected more than 4 million people on earth (IUVA Fact Sheet).

The UVC or Far-UVC light waves, used for sanitizing, are different from UVA light waves, abundantly found in sunlight, as well as from the lesser quantities of shorter UVB light waves, also found in sunlight. UVC light waves are the shortest UV light waves. However, UVC light waves become completely absorbed by the ozone layer, never reaching life on the surface of planet earth. An absorption, which is in fact welcome, since UVC light waves are generally considered more dangerous to life than UVA and UVB light waves. UVC light waves are thus only generated from man-made sources, such as mercury lamps, and more recently LED lamps, in various UV lightwave combinations of blue light, generated in the 200-280nm light spectra, for germicidal effect.

Research highlights on UV light sanitizing technology

Many studies have been carried out on the use of UV light sanitizing technology. Succinctly, the studies test: 1. the efficacy  of various UV wavelengths, fluences (doses) and exposure times for sanitation purposes (e.g.; Oguma et al. 2019; Malayeri et al 2016), and 2. safety in using UVC and far-UVC light for designed germicidal purposes (e.g.; Buonannoa et al 2017; US-HHS2016). In terms of efficacy, results indicate, for example, that varying UVC fluences, exposure times and wavelengths are variously effective in destroying hundreds of pathogens, such as for example the Adenoviruses, Hepatitis A, the Echovirus, the Vibrio cholera, Salmonella typhimurium, Staphylococcus aureus, Escherichia coli and  Heliobacter pylori.  In terms of safety,  direct contact with UV radiation (UVR) is harmful to humans (US-DHHS – NIOSH), with the apparent exception of far-UVC 200-222nm, which has tested safe on human skin cells (e.g., Oguma et al. 2019; US-DHHS2016).

Consequently, the use of different sorts of UV light sanitizing technologies variously require: 1> eyes and/or skin to be shielded, 2> indirect proximity or 3> for the technology to be used in a vacated room. This is the case, for example, in medical settings where industrial UV light sanitizing robots are used for sanitizing vacated operating and patient rooms (e.g.; Xenex Lighstrike™ Germ-zapping™ robot and Altoros disinfecting robot). UVC sanitizing technology is also generally used synergistically with other sanitizing processes, in what is called a “multi-barrier approach” to neutralizing pathogens, in part because UV sanitizing technology cannot sanitize surfaces that are obstructed, or the rear surface of an object (e.g.; Qureshi, Z. and M. Yassin 2013; Trojan UV). Alternatively, UV sanitizing technology might be used as a final step sterilization process. For example, if water cannot be sanitized completely via filtering and the adjunction of chemicals, a UV light process might be added to complete the sanitation process (IUVA). Likewise, if a surface cannot be cleaned of all pathogens with disinfectants, UV light might be used in an adjunctive mode (IUVA). Conversely, since UV sanitizing light cannot reach surfaces under an object, or through organic matter, uses of UV light are combined with prior cleaning and/or disinfection (IUVA).

Use of patented UV light sanitizing technology for air quality 

Hundreds of patents are associated with combination UV light sanitizer technology, in particular, within the context of indoor air quality. A context that is now under increased scrutiny for the crucial step-by-step approach to re-opening economies, post-COVID 19 pandemic wave of infections. For example, a search for UV sanitizing technology for air quality at the EPO (European Patent organization) returned approx.1500 patents. Likewise, several hundred patents were returned at the USPTO. 

As a case in point, the Lighting Science Group Corp, has drawn on extensive experience, designing patented lighting systems both for NASA, and within the context of circadian rhythm research, to design a new line of human-safe UVC light air-sanitizing solutions, trademarked Healthe® Cleanse®. Below, a list of the Cleanse® UVC air-sanitizing solutions for use within the context of the COVID 19 pandemic, together with just a few exemplary patents, disclosing some of the embodied inventions, among hundreds of additional patents that have been awarded to the company’s founders Drs. Fredrik Maxik and Steven Lockley. 

- Cleanse® Air SanitizingTroffers, enabling to combine lighting a room with filtering and sanitizing air, using UVA and UVC light,  targeting pathogens that may remain after HEPA-filtering. 

US8506118 – Light fixture and associated LED board and monolithinc optic.
US7528421 - Surface mountable light emitting diode assemblies packaged for high temperature operation.

US7528421 - Surface mountable light emitting diode assemblies packaged for high temperature operation.

US7824065 - System and method for providing multi-functional lighting using high-efficiency lighting elements in an environment. 

 

Cleanse® Far UVC portal

- Cleanse® human-safe Far-UVC portals, or walkthrough arches, that inactivate pathogens on skin and clothes in less than 20 seconds before a person enters a room.

- Cleanse® human-safe Far-UVC sanitizing lighting, combined with general lighting, for sanitizing surfaces and air, that can be inserted into existing canisters, always-on, or activated only when the rooms are vacated.

 

US10641476 Low profile light.
US10462874 Wavelength sensing lighting system and associated methods. 
US10267465 Downlight apparatus and associated methods of assembly.
US10212781 Wavelength sensing lighting system and associated methods. 
US10072835 Low profile light. 

Beyond air quality, and the potential for decontaminating ambient air, many other sorts of UV light sanitizing products also exists, with a renewed potential for application within the context of the COVID 19 pandemic, such as, for example:

• sanitizing totes for decontaminating personal belongings
• cabinets for quickly sanitizing tools and supplies
• different sorts of UV light sanitizing wands for decontaminating surfaces, re-usable face masks, and clothes,
• various sorts of UV sanitizing containers, such as UV sanitizing cell phone and toothbrush cases
• UV sanitizing flashlights, lamps and bulbs
• …plus more.

References

Altoros Disenfection Robot  - https://www.altoros.com/solutions/uvc-disinfection-robot

Buonannoa, M., Ponnaiyaa,B.,  Welcha,D.,  Stanislauskasb,M.,  Randers-Pehrsona,G., Smilenova,L.,. Lowy ,F.D.,  Owens D.M., and D.J Brenner (2017)  Germicidal Efficacy and Mammalian Skin Safety of 222-nm UV Light. Radiat Research 2017 April ; 187(4): 483–491. DOI:10.1667/RR0010CC.1 - https://bioone.org/journals/radiation-research/volume-187/issue-4/RR0010CC.1/Germicidal-Efficacy-and-Mammalian-Skin-Safety-of-222-nm-UV/10.1667/RR0010CC.1.full

Cantor, C. (April 21, 2020)  “Could a New Ultraviolet Technology Fight the Spread of Coronavirus? Columbia News. - https://news.columbia.edu/ultraviolet-technology-virus-covid-19-UV-light

Cleanse® Downlight – Far UVC sanitation illumination - https://healthelighting.com/products/cleanse-downlight

Cleanse® Air Sanitizing Troffers - https://healthelighting.com/products/cleanse-air-sanitizing-led-retrofit-troffer

Eadicicco, L. (June 15, 2020)  'Cleanse portals' that zap away germs with ultraviolet light are starting to appear as businesses begin to reopen amid the COVID-19 pandemic. Business Insider.  - https://www.businessinsider.com/uv-light-cleanse-portals-used-to-kill-germs-coronavirus-2020-6

Healthe®  by Lighting Science. - https://healthelighting.com/

Healthe® Develops Human-Safe Ultraviolet Light Solutions to Help Combat Spread of Infection, Get People Safely Back to Work.  Cleanse® Series Provides Added Protection for Hospitals, Schools, and Offices. - https://www.globenewswire.com/news-release/2020/04/29/2024174/0/en/Healthe-Develops-Human-Safe-Ultraviolet-Light-Solutions-to-Help-Combat-Spread-of-Infection-Get-People-Safely-Back-to-Work.html

IUVA (1) – International UltraViolet Association – IUVA Fact Sheet on UV disinfection for COVID 19. - https://iuva.org/IUVA-Fact-Sheet-on-UV-Disinfection-for-COVID-19

IUVA (2) Advice for the selection and operation of equipment for the UV disinfection of air and surfaces. - https://iuva.org/Advice-selection/operation-of-equipment-for-the-UV-disinfection-of-air-and

Lighting Science Group Corporation  (now Healthe®) – Patents. - https://lsgc.com/patents/

Lighting Science Group Corporation announces issuance of 35 patents. https://www.businesswire.com/news/home/20160202006068/en/Lighting-Science%C2%AE-Announces-Issuance-35-New-Patents

Malayeri, A.H.,Mohseni, N. Cairns B. and J.R. Bolton (2016) Fluence required to achieve incremental log inactivation of bacteria, protozoa, viruses and algae. IUVA NEWS  13(3), 4-6.   https://www.ews.com.gt/user_files/uploads/UV_Dose_List_IUVANews_Fall2016_UVSensitivityReview_full.pdf

Martin, H. (June 23, 2020) His plane disinfecting invention didn’t take off --until COVID 19 hit. Los Angeles Times. - https://www.latimes.com/business/story/2020-06-23/plane-disinfecting-honeywell-covid-19

Oguma, K., Ratanacul, S. and M. Madaike (2019) Inactivation of health-related microorganisms in water using UV light-emitting diodes. Water Supply (2019) 19 (5): 1507–1514. - https://doi.org/10.2166/ws.2019.022   https://iwaponline.com/ws/article/19/5/1507/65644/Inactivation-of-health-related-microorganisms-in

Ohnaka, T. (1993) Health effects of UVR (Ultraviolet Radiation). Ann Physiol Anthropol. 1993 Jan;12(1):1-10. DOI: 10.2114/ahs1983.12.1  - https://pubmed.ncbi.nlm.nih.gov/8507288/

Qureshi, Z. and M. Yassin (2013) Role of Ultraviolet (UV) Disinfection in Infection Control and Environmental Cleaning. Infect Disord Drug Targets- 2013 Jun;13(3):191-5. DOI:10.2174/1871526511313030007  - https://pubmed.ncbi.nlm.nih.gov/23961739/

Rammelsberg, A. (Aug. 17, 1998) How does UV light kill cells? Scientific American.  - https://www.scientificamerican.com/article/how-does-ultraviolet-ligh/

Trojan UV - Introduction to UV disinfection. -  https://www.trojanuv.com/uv-basics?acceptCookies=1

US-DHHS (2016) Ultraviolet-Radiatio-Related-Exposures- 14^th Report on Carcinogens, Nov. 3, 2016) - National Toxicology Program -  Department of Health and Human Services.  - https://ntp.niehs.nih.gov/ntp/roc/content/profiles//ultravioletradiationrelatedexposures.pdf

US-DHHS – NIOSH Ultraviolet Radiation and the Work Environment (Revised. See: 74-121). -  https://www.cdc.gov/niosh/docs/73-11005/default.html

Xenex Disinfection Services - LightStrike™ Germ-Zapping™ Robots.  - https://www.xenex.com/our-solution/lightstrike/