UV-C ultraviolet lamps are used to disinfect all types of spaces and surfaces, as well as to sterilize medical and laboratory instruments. Due to the needs caused by the COVID-19 health crisis, this type of disinfection has potentially increased.
One of the greatest advantages of these luminaires is that the disinfected areas can be used immediately after disinfection is complete, provided that the direct radiation has been terminated.
But what are UV-C luminaires?
The UV spectrum is divided into three groups based on its wavelength:
- Ultraviolet C (UV-C)radiation is the most damaging. It has a shorter wavelength of light than the others, 100-280nm. It has a strong bactericidal and germicidal effect. UVC radiation is completely absorbed by the ozone layer.
- Ultraviolet B (UV-B) radiation has a wavelength of 280-314nm. This type of radiation represents a maximum 10% of the radiation that reaches the earth’s surface. It has applications in radiotherapy.
- Ultraviolet A (UV-A) radiation has a long wavelength of 315-399nm. UVA radiation is barely retained by the atmosphere, being 90% of the radiation reaching the earth’s surface.
How does UV-C disinfection work?
Microorganisms are deactivated by absorbing the energy of UV-C radiation by ribonucleic acids. This absorption of energy causes a breakdown of DNA and RNA until they are eliminated.
UV-C lamps for disinfecting room air are normally mounted above head height and continuously operate to disinfect circulating air.
What applications do these luminaires have?
This type of disinfection was discovered in 1878, becoming a fundamental sterilization method.
Its scope of application is very wide, covering hospitals, airplanes, factories, offices, places for food, etc. It is used, for example, for disinfection in sewage treatment plants, laboratories, air conditioning systems and even swimming pools and aquariums, as well as in different stages of the industrial processes of food and beverages.
What are the advantages of UV-C disinfection systems compared to other systems?
As we have already mentioned, one of its main advantages is that the disinfected areas can be used immediately after the disinfection is finished. On the other hand, it is faster and cheaper than traditional disinfection systems.
No pathogen is resistant to UV-C light, unlike what happens with other disinfection systems, and behaves in the same way for different types of pathogens, whether they are viruses, fungi, bacteria, etc.
Finally, it is a chemical-free process that does not generate waste and is not toxic.
UV-C luminaires today
This disinfection method has been recommended by the WHO (World Health Organization)
In the context of the COVID-19 pandemic, UVC light is used in the United States to disinfect subway cars and buses. On the other hand, in China, the cleaning of hospitals is done with robots with this light and buses are disinfected every night.
According to a recent report on the efficacy and safety of disinfection with ultraviolet light carried out within the framework of the Work Plan of the Spanish Network of Health Technology Assessment Agencies and SNS Benefits:
“The available evidence suggests that UV-C light devices could inactivate SARS-CoV-2 easily and quickly. However, the available evidence is still scarce and very heterogeneous. “
In relation to this study on UV-C radiation, the Ministry of Health adds the following:
- “UV-C radiation cannot be applied in the presence of people.
- Applicators must have the appropriate protective equipment and must demonstrate specific training on the safety requirements of devices or equipment that use UV-C radiation.
- Improper use of this equipment can cause possible harm to human health and give a false sense of security. The use of these equipment or devices for domestic use is not recommended.
- The use of UV disinfection lamps to disinfect the hands or other skin areas is not recommended unless clinically justified.
- Professional UV-C installers must inform customers about compliance with the UNE 0068 Specification and the main aspects related to safe use and not exceeding the exposure limits. “
In any case, the Ministry of Health insists that the most effective measure for the prevention of SARS-CoV-2 infections continues to be hand washing, protection with a mask, social distance, cleaning with detergents and disinfectants and the application of authorized biocides.