Current world events have instigated much dialogue pertaining to Ultraviolet light sterilization as an effective way to sterilize homes, businesses and medical facilities including hospitals. UVC robots are being deployed in many facilities to stop the spread of harmful germs and improve the health and comfort of people in various commercial environments.
Ultraviolet (UV) light has proven effective at eliminating the threat from many well known viruses, dating as far back as 1877 when the first scientific study was recorded concluding that Ultraviolet light provided powerful sterilization properties. Further studies in the early 20th century confirmed that Ultraviolet light could prevent the spread of infections diseases, on surfaces and in the air, yet it would take many more decades for science and medicine to harness the power of Ultraviolet radiation.
With the increase of tuberculosis in the 1980’s, Ultraviolet light was once again brought to the forefront of medicine and used to combat the spread of this highly contagious and deadly infection. Ultraviolet lamps are now being used in many widespread germicidal applications to eliminate harmful pathogens in air, water and on surfaces. Even with an increase in the use of UV lamps for sterilization, there are still many environments that stand to gain a great deal and improve public health by utilizing Ultraviolet light sterilization systems.
The Spectrum of UV Light: UVA, UVB, UVC
Ultraviolet (UV) light is electromagnetic radiation with a wavelength that is shorter than visible light and longer than x-rays, emitted at 100 to 400 nanometer (nm). The UV spectrum is divided into:
- UVA 315 to 400 nm
- UVB 280 to 315 nm
- UVC 200 to 280 nm
- Vacuum UV 100 to 200 nm
UV radiation emitted predominantly at 253.7 nm effectively inactivates microorganisms and is referred to as Ultraviolet germicidal irradiation (UVGI). UVGI interrupts the transmission of pathogenic organisms including bacteria, viruses, mold and even bioterrorism agents.
UVGI is proven to be effective in air handling systems to prevent the spread of disease through circulated air and on surfaces and is also effective in many water sterilization applications. UVC sterilization is becoming increasingly popular as concerns about the quality of indoor air increases.
Ultraviolet Light Sterilization Effectively Eradicates Microorganisms
Infectious diseases are transmitted by various means, through human touch or secretions, droplets in the air and on surfaces. UVC irradiation is proven to inactivate many microorganisms such as vegetative bacteria, spores, fungal spores and viruses. Individual species may be more resistant to UVC exposure and require the proper fluence rate for inactivation.
Ultraviolet light provides effective germicidal irradiation on the following bacteria and microorganisms:
Vegetative bacteria, Staphylococcus aureus, includes individual species such as:
- Streptococcus pyogenes
- Escherichia coli
- Pseudomonas aeruginosa
- Serratia marcescens
Viruses which are susceptible to UVGI include:
- Influenza viruses
Both vegetative bacteria and viruses are generally most susceptible to UV inactivation, followed by microorganism groups including Mycobacteria, bacterial spores, and finally fungal spores.
Mycobacteria includes the following species:
- Mycobacterium tuberculosis
- Mycobacterium bovis
- Mycobacterium leprae
Bacterial spores include:
- Bacillus anthracis
- Bacillus cereus
- Bacillus subtilis
Fungal spores include:
- Aspergillus versicolor
- Penicillium chrysogenum
- Stachybotrys chartarum
Spore forming bacteria and fungi also have vegetative forms which are markedly more susceptible to UV inactivation that other spore forms. The effectiveness of Ultraviolet light sterilization for the inactivation of tuberculosis, measles and influenza was established in various medical journals (Escombe et al. 2009; Mphaphlele et al. 2015).
Ultraviolet Light Sterilization in Air Handling Units
Harmful pathogens such as measles, tuberculosis bacterium and influenza viruses are all infectious organisms which are known to be transmitted indoors by shared air space, between infected and susceptible persons. This occurs in congregated spaces such as within a room and beyond a room such as in corridors and even through ventilation ductwork.
Low-pressure mercury vapor lamps are the standard source of UVC lamps in commercial systems, with an optimum wavelength of 253.7 nm. UVC lamps in air handling systems improve the indoor air quality (IAQ), enhancing the health, comfort and productivity of occupants.
UVGI for Residential Air Purification
According to a report by the Environmental Protection Agency (EPA) Indoor Environments Division in July of 2018, regarding the use of air cleaners for residential use, there are two types of UVGI applications for residences. UVC lamps are designed for airstream disinfection to reduce microorganisms as they flow through the HVAC system or they can be designed for surface disinfection to prevent microorganism growth on cooling coils in the HVAC unit. Numerous studies show that the most important components of a UVGI system are the type of UV light and ballast, air velocity, temperature, relative humidity and duct reflectivity.
UVGI in Healthcare Facilities
When UV lamp sterilization systems are used in air handling units (AHU) in conjunction with a particulate filtration system, efficacy improved to 98%. If a particulate filter removes 85% of agents from an incoming airstream and UVGI eliminates 85% of microorganisms with single-pass efficacy, it provides an effective incremental benefit. This study showed a reduction in CFU counts of 99% in just one month when Tier 1 UVGI in AHU was used in a major hospital in Mumbai.
Conclusion of multiple studies show that UV light for sterilization in air and surface treatment systems are effective, economical and flexible for hospital air disinfection with no residual side effects.
LightSources Offers Ultraviolet Light Sterilization Solutions
LightSources along with our strategic partner, LightTech, provide benefits to OEMs of all sizes with proprietary, unique germicidal solutions. We provide UV lamps for ultraviolet light sterilization applications such as:
- Air sterilization and HVAC UVGI
- Odor control
- Water purification
- Sewage treatment
- Food processing and protection
We offer a wide range of innovative, high-quality UVC germicidal lamps as well as custom designed products to meet your specific application requirements. Our UV lighting engineers design high-tech UV lamps with custom phosphor blends, based on a deep technical knowledge of UV radiation.
We provide full OEM support with prototype development and customized germicidal solutions. Our adherence to a strict quality policy as part of our ISO9001:2015 certification ensures quality products and processes to meet your specific needs.
LAMP PRODUCT DATA:UV Germicidal Lamps
LAMP Applications:UV Germicidal Applications
LightSources leads the UV lamp industry with innovative, first-to-market products and proprietary solutions which increase your brand awareness. We support OEMs worldwide with patent-protected, quality UV lamp solutions. Contact us to speak with an engineer about our high-performance, quality lamps for Ultraviolet light sterilization.