In Room Solutions are key for use cases with acute disinfection needs.
For In Room Disinfection, facility owners, operators, and administrators have multiple choices when it comes to cleaning the air. Stand alone floor or counter devices typically include fans to draw the past the ultraviolet luminaires. Ceiling fixtures are available as well and some have fans to increase the air flow. Other choices include devices where occupants need to be cleared from the room during the ultraviolet disinfection. This is an example below of a wall mounted device that accomplishes the maximum combination of safety and disinfection, while occupants can remain in the room. The scientific information below provides more details and this particular device series has been proven, with installations in hospitals and other facilities over the past 50 years. Over 50,000 ultraviolet devices by this particular US manufacturer have been installed to date.
WALL MOUNT DISINFECTION with Germicidal UV Light The Wall Mount in-room devices can acutely treat vulnerable or high traffic rooms, such as healthcare waiting rooms, and they are also well suited for K-12 and university classrooms. For this solution, the self-contained and louvered “shoe box” device is mounted on the wall approximately 7’ from the floor. The natural conductive flow of air in the room circulates the sanitized air, from the existing HVAC system as well as the opening and closing of doors and human movement. The UVC devices come in three sizes that are increasingly larger relative to the respective coverage area. For each coverage area, the dimensions are listed here by Width x Height x Depth. Please note that multiple devices can be used in rooms or areas larger than 300 sq ft. 300 sq ft coverage (37.5” x 5.2” x 6.6”); 200 sq ft (27.7” x 5.2” x 6.6”); 100 sq ft (10.8” x 9.2” x 9.1”). Plus, corner devises are also available. SPECIFICATION SHEET
This device series comes in three different sizes to match the approximate size of the rooms, and multiple devices are recommended for areas larger than 300 sq ft.
Samples and full orders are currently backlogged given production demand. Production and delivery time is typically three (3) weeks.
Combination Wall & Ceiling Mount Devices: Surgical Operating Rooms have set the precedent for disinfection. Some Dentists are following the lead and using ceiling mounted fixtures in conjunction with the wall mounted devices to enhance disinfection of surfaces in addition to cleaning the air. Since the ceiling mounted fixtures require clearing the room of occupants and setting a timer for about 10 minutes, the application is only appropriate for Dental Operatories that have a door to prevent people from entering during the ceiling fixture surface disinfection.
WHICH SOLUTION IS BEST FOR MY FACILITY?
If you are also considering a germicidal UV light system with duct and/or coil applications vs the in-room wall mounted devices, it is most beneficial to combine the HVAC Duct with the Coil & Pan devices, for maximum disinfection. This approach provides intensive ultraviolet treatment with the added advantage of maintaining the performance of the coil and drain pan system for added longevity. The HVAC Duct devices can easily go anywhere in the ducts, while the Coil & Pan treatments typically need more planning for retrofits based on certain space confinements. Since the Wall Mount in-room devices can acutely treat vulnerable or high traffic rooms, such as healthcare waiting rooms, at quicker rates, consider a “Triple-Purge-Virus” approach. All of the solutions have similar overall results reducing airborne contaminants by over 99 percent, depending on the microbes.
Since the second half of the 20th century, one of our US production partners has manufactured more than 50,000 germicidal UV light devices. The client list is extensive, and here are just a few examples of major accounts:
Institutions: Infectious Disease Research Institute
Healthcare: New York State Department of Health, Albert Einstein Medical Center, Burbank Hospital, Children′s Hospital Medical Center of Boston, Methodist Healthcare of San Antonio
Food/Beverage: Safeway Stores, Anheuser-Busch, Campbell Soup, Coca-Cola, Pepsi Cola, Del Monte, Dr. Pepper/7-Up, General Foods, Gerber Products, Guinness, Heinz, Hershey’s, Kraft, M&M/Mars, Minute Maid, Ralston Purina, Pepperidge Farms
Education: Princeton University, Cornell University, Johns Hopkins University, Ohio State University
Pharma: Merck, Bristol-Myers Squibb, Eli Lilly
US Government: US Army, Air Force and Naval Hospitals, US Veterans Administration Hospitals, US Department of Agriculture, US Food & Drug Administration
Other customers you may recognize: IBM, 3-M, Dupont, Union Carbide, Proctor & Gamble
The Science Precedes COVID-19
(Read before purchasing any equipment)
1. Scientific Highlights: The Sun generates Ultraviolet (UV) light across the wavelength range in nanometers from 100-400 nm. UV is divided into three bands: UVA (315-400 nm), UVB (280-315 nm), and UVC (100-280 nm). The ozone layer in the stratosphere absorbs UVC. Life on Earth has evolved without exposure to UVC, which makes a broad range of life forms vulnerable if exposed to it. The UVC photons are energetic enough to damage the DNA and RNA of microorganisms, destroying their ability to replicate. Different microorganisms respond differently to UVC. Viruses are very susceptible to it, bacteria are less susceptible, and fungal spores are the least susceptible. This means that applying the right dose of UVC is the key to killing the pathogens.
2. Technology Highlights: The lamps used in the devices described above are similar to typical fluorescent tubes in offices around the world, but they do not have the phosphorescent coating which delivers the soft white light. Many commercial UVC lamps are low pressure mercury lamps that emit UV energy at 253.7 nm, which is an ideal wavelength for disrupting the DNA of microorganisms such as viruses. The wavelength of the devices described on this page is 253.7 nm. The Center for Disease Control and Prevention (CDC) and The National Institute for Occupational Safety and Health NIOSH have recommended permissible exposure limits for different UV wavelengths. For UVC, at 253.7 nm wavelength, the recommended exposure limit (REL) is 6,000 joules per centimeter squared (6 mJ/cm2) for a daily 8 hour work shift. UVC devices are being used at increasing levels all over the world in various form factors and applications to disinfect water, air and surfaces.
3. Safety and Disinfection Dosage: When people enter the room, they see a blue glow coming from the wall mounted UVC device, described above. Time, intensity, and distance = dose. At the device intensity, an occupant would have to stand on a chair and stare straight into the light for a while to achieve the harmful levels of dose. At 10 ft away from this device, the intensity factor is .115. The intensity at 1 meter is 120 uW/cm2 (Micro-Watts per square centimeter) and at 10 feet away the intensity is 13.8 uW/cm2. This is key, because effective germicidal impact is over 10 uW/cm2. (chart below). In joules per second, this equates to 0.0138. This device has been engineered and installed over many years at many facilities to provide the key combination of both safety and disinfection. See: Reducing Infectious disease transmission with ultraviolet germicidal irradiation (UVGI) – ASHRAE Report 2020-2017
4. Pros and Cons of Direct Dosage vs Fan Based Systems: Irradiating pathogens does not happen instantly. Disrupting the DNA of microorganisms such as viruses can take up to 100 seconds, subject to germicidal UVC dosage levels. Fan based devices come in many shapes, sizes, and price points. Some of them are designed to be placed on the floor or a counter, while others are designed for ceiling installation. Regardless of the form factor and location, fan based devices typically draw air into the equipment, partially treat it, and exhaust it without fully irradiating the pathogens. The cycle then continues. With these types of devices, the air speed passing the UV or UVC luminaire is a key factor in addition to the wattage of the luminaire relative to the number of pass-by air intervals needed to fully kill the pathogens. For a 10’ x 12’ room with a 9’ ceiling (approx 1,000 cubic feet), it may take 15 minutes or more to clean the air in the room. Plus, the sides and corners of the room farthest from the fan device is treated less acutely than the air near the device. By contrast, direct dosage devices, such as the upper air wall mounted technology described on this page, can irradiate all of the air in the same size room within 5 to 7.5 minutes. This is due to the fact that code compliant HVAC systems in rooms, such as dental operatories, have 8 to 12 Air Changes per Hour (ACH). The air moves slowly around the room and across the ceiling giving the UV time to kill the pathogens rather than rushing it by the UV elements inside of a fan based device. The result is faster and more thorough air disinfection with direct dosage. There is a place for fan based devices or in-duct devices for properties such as office buildings that do not need acute disinfection. Dental operatories and other healthcare facilities warrant the most aggressive form of pathogen irradiation, as do certain quick serve restaurants and other facilities with high traffic of different people moving though the space.
5. UVC and UV: Not all ultraviolet wavelengths are created equal when it comes to irradiating pathogens. Ultraviolet-C (UV-C) is between 100 and 280 nanometers (nm). UVC has been proven to have an incredibly high capacity to kill pathogens, including viruses. UV is a broader range 100-400nm, and 405nm is just outside of UV and is used by some manufacturers. The 405nm wavelength has demonstrated capacity to reduce the mitigation of some viruses, but it is not as potent as UVC. Remember that time, intensity, and distance = dose. While the number 405 is higher than 100-280, the intensity is inverted. The devices described here use 253.7nm, which is the peak performance for germicidal effectiveness. (See chart below and ASHRAE Report 2020-2017). When considering a UV or UVC device, ask your potential service or technology provide about the nanometers used in the equipment. Facilities with acute needs such as dental operatories and other healthcare facilities warrant germicidal UVC light, as do certain quick serve restaurants and other facilities with high traffic of different people moving though the space.
- ASHRAE Handbook (2020). Position Document on Airborne Infectious Diseases – Reaffirmed by Technology Council February 5, 2020.
- ASHRAE Handbook (2016). HVAC Systems and Equipment, Ultraviolet Lamp Systems. Ch. 17 Section 5 Safety – Exposure Limits. Recommended exposure limit (REL) 8 hour work shift for UVC.
- ACGIH (2015). Theoretical Limit Values and Biological Exposure Indices, Cincinnati Ohio.
- Kauffman R (2011). Study the degradation of typical HVAC materials, filters and components irradiated by UVC energy. ASHRAE Research Report RP-1509.
- IESNA (2000). Lighting Handbook: Reference & Application IESNA HB-9-2000, New York.
- Harm W (1980). Biological Effects of Ultraviolet Radiation, New York. Cambridge University Press.
- NIOSH (1972). Criteria for a recommended standard: Occupational exposure to ultraviolet radiation. Publication 73-11009, Washington D.C.
May 4, 2020: Ultraviolet Light Kills Coronavirus, But Caution Required. Source: Facilities Net
“One safer option for using UV-C technology in occupied space is upper-room germicidal ultraviolet (GUV). In this application, UV-C fixtures are used to continuously irradiate the air above 7 feet from the floor”