By Bobbi H. McLeod, LC, Lumenal Lighting
Lumenal Lighting, a Seattle area design-build lighting and electrical contractor with 40 years of experience, recently expanded its offerings to include germicidal UV solutions. In response to the recent vigilance uptick regarding the spread of harmful pathogens, the designers at Lumenal Lighting embarked on a fact-finding mission. They wanted to determine if and how lighting and UV energy could be safely deployed to combat germs, bacteria, and viruses.
Ultraviolet (UV) energy is the section of the electromagnetic spectrum measuring 400 to 40 nanometers (nm). Visible light ranges from 740 to 380 nm. If one remembers grade school science class, UV exists just past good old ROY G. BIV. Both UV and visible light can be used for disinfection, but there is one range of the electromagnetic spectrum that is the undisputed champion in the fight against germs, bacteria, and viruses.
Germicidal Ultraviolet has a Long History of Success
Ultraviolet energy ranging from 280-200 nm is called UVC. Hospitals have been using UVC germicidal lamps for 90 years to combat drug-resistant superbugs, viruses, and bacteria. It was particularly useful against a tuberculosis outbreak spike in the 1980s. With the increased adoption of vaccines and antibiotics in the latter half of the 20th century, the need for UVC solutions ebbed slightly. It is possible that increases in drug resistance and novel viruses will once again give UVC the opportunity to be the hero.
However, the effectiveness of UVC is also its greatest obstacle for widespread implementation. UVC will cause damage to human skin and flash burns in eyes if directly exposed. Safe deployment requires extensive design, careful maintenance, and strict operational procedures. Designers must consider the environment in which UVC is being installed to mitigate risk of reflective effects from ceilings, walls, and floors. Maintenance crews must be given training and personal protective equipment to safely change lamps when needed or operate mobile UVC tools. Control measures must be used to ensure that UVC lamps are not energized and activated when non-protected personnel are in the vicinity. When the power of UVC is harnessed by safety precaution adherence, it is a proven weapon in the fight against photosensitive pathogens.
Germicidal UV lamps, measuring specifically at 254 nm, is the documented frontrunner in virus inactivation. It is even showing promise against SARS-CoV-2, the virus that causes COVID-19, based on recent validation by Boston University. Further studies are inevitably in process and the design team at Lumenal Lighting eagerly awaits successful results.
Form Factor Variety Allows for Widespread Implementation
Germicidal 254 nm UV lamp technology is available in several form factors for installation flexibility and/or mobile use. If the application could ensure that rooms are unoccupied when the UVC is in use and sensors turn off the fixture when movement is detected, then permanent fixtures could be installed. They are available in troffers, linear strips, high bays, and other familiar fixtures. These fixtures would be installed in addition to existing fixtures for illumination, not replacements.
Mobile and handheld UVC solutions may prove a cost-effective solution for businesses and facilities. The mobile unit is wheeled into the focus space by a trained operator, donning full protective gear. The mobile unit is then energized via remote from a safe location. Once the appropriate dosage is distributed, the operator powers down the unit and relocates it to the next space. Alternatively, large handheld units can be used by fully protected operators. This method may work well on athletic gear, personal protection equipment, tools, and other items. Additionally, either the mobile or handheld units could be used in airplanes, buses, and other mass transit, where permanent fixture installations are not feasible.
Upper Room Germicidal Irradiation (UVGI) Integrates UV with Air Flow
UVGI is a very specific procedure that pairs indirectly installed UVC near the ceiling with slow-moving air circulation. The slow-moving air may be provided by a ceiling fan or the result of a ducted ventilation system. This method addresses aerosolized pathogens and redistributes the treated air into the space. There are some fixtures where room occupants are not exposed to the UVC component, rendering it a much safer application. Special care would still have to be taken by maintenance personnel when servicing the fixture.
UV lighting should be looked at as one of several steps we can take to improve the safety of the environment in which we work and live. It must be employed carefully, but properly done, it can be very effective.
Designers and end-users absorb the daily alerts about advances in UV and other germicidal technologies and the resulting studies on their effectiveness. It is important to note that energy solutions will not replace manual sanitizing procedures. The best method is the overlap of multiple efforts; think a belt and suspenders approach. Reach out to Lumenal Lighting to explore your germicidal UV options, wear your mask, and wash your hands.
Illuminating Engineering Society – IES CR-2-20-V1, Germicidal Ultraviolet (GUV) https://www.ies.org/standards/committee-reports/
XtraLight® UVC High Power Ultraviolet Disinfection System https://info.xtralight.com/en-us/uvc-ultraviolet-disinfection-system
Cooper Lighting Solutions Fail-Safe GUV Disinfecting Solutions http://www.cooperindustries.com/content/public/en/lighting/resources/LightingStories/guv/products.html
Signify and Boston University validate the effectiveness of Signify’s UV-C light sources on inactivating the virus that causes COVID-19 https://www.signify.com/global/our-company/news/press-releases/2020/20200616-signify-boston-university-validate-effectiveness-signify-uvc-light-sources-on-inactivating-virus-that-causes-covid19