UV-C Disinfection Systems & Devices

Ultraviolet rays are electromagnetic waves that form part of the light (Fig. 1). Electromagnetic waves are divided into three main wavelength bands, expressed in nanometres (nm): Ultraviolet (UV) rays 100-400 nm Visible (light) rays 400-700 nm Infrared (IR) rays 700-800,000 nm. UV rays, in turn, are broken down into three bands:

UV-A (315-400 nm) with tanning properties;
UV-B (280-315 nm) with therapeutic and vitamin “D” synthesising properties;
UV-C (100-280 nm) with germicidal properties.

UV-C rays (100-280 nm) have a strong germicidal effect and reach their maximum efficacy at the 265 nm wavelength. The germicidal effect of UV-C radiation covers bacteria, viruses, spores, fungi, moulds and mites; this is mainly due to the destructive effect of the UV-C rays on their DNA, which damages their reproductive system and prevents them from replicating.

Bacteria, viruses, spores, fungi, moulds and mites are all sensitive to UV-C rays and can be eliminated by them.
Microbes cannot acquire resistance to UV-C rays, which only occurs using chemical disinfectants and antibiotics.

UV rays are eco-friendly. When using normal disinfectants, environmental pollution is inevitable. They also carry severe risks from the direct inhalation of vapours or the ingestion of foods contaminated after coming into direct contact with chemical disinfectants.

Where the use of chemical disinfectants is unavoidable (food/pharmaceutical/healthcare industries, etc.), using ultraviolet rays in the disinfection process can reduce the amount needed, which allows for significant cost savings and is better for the environment, while maintaining – and, most of the time, improving – disinfection quality.

UV-C ray devices can be installed in most environments and machinery and can be programmed to maintain the same level of disinfection day and night, ensuring ideal conditions of hygiene without any fluctuation in quality. In contrast, chemical disinfectants are most effective at the time of use.

LIGHT PROGRESS UV-C-equipped devices offer low running costs and are maintenance-free, besides normal bulb replacement. These powerful and highly durable systems provide exceptional value for money. For this reason, eliminating germs using UV-C as opposed to (or together with) other systems offers excellent results at a low cost.

UV-C rays really work. The difference between an ineffective application and a quality project lies in our in-depth knowledge and long-term experience in the area. Since 1987, Light Progress has successfully completed projects all over the world and built up a portfolio of clients, including companies from all industries that require verified conditions of hygiene to produce quality products or services.

Multiple organisations and boards with a global reach, such as WHO, EPA, CDC, ASHRAE and many others, recommend using UV-C rays to disinfect water, environments and air-conditioning systems. LIGHT PROGRESS is a member of the IUVA (International Ultraviolet Association), a global organisation that collects and gives users access to all available information and which organises various international meetings each year. Having collected all this information, the IUVA has also published a document that lays the foundations for designing different UVGI (Ultraviolet Germicidal Irradiation) systems and applications.

Each bacterium, virus, yeast, mould or mite requires a different UV-C dose to be deactivated or eliminated.
There are widely recognised documents that report these levels. Light Progress has one of these documents and uses it regularly in designing and implementing its systems. To give an approximate idea regarding the application times of UV-C rays, these can range from fractions of a second to several seconds.

Viruses, bacteria and mould, animal waste, mites and pollens are among the main causes of dangerous infections and allergies.

Each of these contaminants is dispersed in a different way: mites, spores, bacteria and mould, for example, are continuously transported by air, while other bacteria and viruses are “grouped” into solid particles, such as spores or drops of moisture, and then inhaled by humans.

In air conditioning systems, when contaminants get inside the air treatment unit (ATU) and air distribution ducts, the system, which is dark and moist, becomes a breeding ground for them to grow and multiply, making the air we breathe unsafely.

The air also contains concentrations of chemical pollutants which are dangerous if inhaled in large quantities or on a continuous basis.

Irradiating air in a central system or installing an air purifier complete with UV-C lamps and a TiOx titanium dioxide filter greatly reduces the likelihood that these pollutants (whether microbiological or physicochemical) will result in health problems that often can only be diagnosed after many years.

The efficacy of disinfection systems can easily be tested through microbiological analysis, or simply using buffers to check for the presence of microorganisms on the surfaces being tested. However, accurately verifying the quantity of microbial load found on a surface, in the air or in water before and after treatment requires laboratory tests, such as HACCP.

In the case of chemical disinfectants, manufacturers indicate preventive tests under their disinfecting capacity; Light Progress has also carried out important tests at university and accredited Sinal (Accredia) laboratories. Of course, for both chemical disinfectants and UVGI technology, in order to obtain the same results as the laboratory, the product must be used according to the descriptions given in its instructions for use.