UV-C Light for healthcare

COVID-19: Our UVGI Solutions


At this time of global crisis due to the effects of the spread of Covid-19, Light Progress is receiving a significant number of requests from all over the world. Our systems safeguard people’s health and enable healthcare professionals to work much more safely.



Our company has always been committed to preventing contamination and increasing safety by controlling cross-contamination in all areas: surface treatment, air quality, and water purification. UVGI is an established and reliable technology, but solid know-how is required for effective and safe use. UVGI uses ultraviolet light to inactivate microorganisms by cross-linking thymidine nucleotides in DNA and uracil nucleotides in RNA, which block replication. UVGI systems are relatively fast and easy to use, leave no chemical residues, and do not expose workers to harmful substances. Currently, there are no specific tests on UV resistance of Coronavirus SARS-Cov-2. Still, there are examples of scientific literature about the UV-C treatment of very similar viruses, such as SARS or MERS.

There is also evidence of the effectiveness of ultraviolet rays in disinfecting air and surfaces from microorganisms that are much more complex and difficult to treat than this virus. These include C. DifficileMRSA, or even more deadly threats such as Ebola and Legionella. (Kowalski 2009) It is estimated that the SARS-CoV-2 virus can survive on surfaces for up to nine days, based on its similarity to SARS and MERS.

Standard disinfectants are effective against SARS-CoV-2, but to provide additional protection and defend against errors in the manual disinfection process, UVGI can be used to disinfect surfaces and equipment following manual chemical disinfection. “ASHRAE” (American Society of Heating, Refrigerating and Air-Conditioning Engineers) recommends ultraviolet germicidal irradiation to address disease transmission of COVID-19.

UV irradiation in air conditioning and air treatment systems has been recommended for many years. Light Progress UV systems for air conditioning are already widely used in many sectors: hospitals, industry, transport networks, and residential centers. For more information, see the HVAC section of our website.



UVGI has been successfully tested in laboratories to decontaminate N95 masks exposed to MS2 bacteriophage and influenza virus.

In recent weeks our distribution network in the healthcare sector has been working non-stop. Our partners are professionals and experts in infection control, and they have provided us with numerous application ideas, which can – or indeed, must – be shared as much as possible. Lights4Health, our partner in the Netherlands, has just provided the SEH department (First Aid) at Leiden University Medical Center with UV treatment cabinets. The systems will disinfect N65 masks in use by medical and paramedical staff.

Two studies on the UV-C treatment of masks were published in leading scientific journals in 2015 and 2018, respectively, well before the recent release of Covid-19.

  • National Institutes of Health: Effects of Ultraviolet Germicidal Irradiation (UVGI) on N95 Respirator Filtration Performance and Structural Integrity

  • American Journal of Infection Control: Ultraviolet germicidal irradiation of influenza-contaminated N95 filtering facepiece respirators

The problem of finding masks is a constant in analyzing possible “apocalyptic” scenarios regarding managing a global pandemic. One of the texts reports:

“The possibility of a global pandemic of an infectious respiratory disease is of tremendous concern to the occupational health community because healthcare workers would face the most significant risk of exposure. For pandemic diseases that airborne particles may transmit, the isolation precaution guidelines from the Centers for Disease Control and Prevention (CDC) call for healthcare workers to wear respiratory protection while treating patients. Because of their loose fit and low filtration capacity, surgical masks do not provide respiratory protection against tiny airborne particles.

For this reason, the most common respiratory protection device in healthcare settings is the disposable N95 filtering facepiece respirator (FFR). However, infection control procedures typically require disposable FFRs to be discarded after a single use to avoid cross-contamination. This means that a pandemic of a disease such as influenza would require a tremendous number of FFRs to protect healthcare workers from airborne transmission. The Institute of Medicine (IOM) projected that a 6-week influenza pandemic would require 90 million FFRs. The Occupational Safety and Health Administration (OSHA) has predicted that an influenza pandemic would likely last 24 weeks, which suggests that up to 360 million FFRs could be needed in the United States alone. A surge in demand of this magnitude would significantly exceed current stockpiles and production capabilities and almost certainly result in a shortage.”

During the 2009 H1N1 pandemic, the CDC (“Centers for Disease Control and Prevention” USA) recommended that healthcare facilities consider extending the use and reuse of N95 respirators in cases of extreme need. One way to meet the growing demand for masks during a pandemic would be to reuse them. This is because even a small number of reuses of each mask would greatly expand the available stock of disposable respirators. Buying masks in bulk represents a high cost, in addition to the difficulties associated with the production and distribution processes.

However, a significant concern for reuse is the possibility that the external surfaces of the respirator may become contaminated with infectious material and lead to disease transmission. To avoid this risk, masks should be decontaminated after each use. Several techniques have been tested for the decontamination of N95 FFR. These include autoclaves, steam generated by heat or microwaves, ethylene oxide, vaporized hydrogen peroxide, and bleach. All the methods described have advantages and disadvantages. Heat and moisture, for example, may dissolve or degrade the respirator and require the device to dry after treatment. Chemical disinfectants require rinsing and drying and may leave an unpleasant odor or residue that irritates the skin. Gaseous systems using ethylene oxide or vaporized hydrogen peroxide require specialized equipment and ventilation controls.


N95 systems cannot be disinfected with alcohols such as isopropanol because they remove the electrostatic charge from the filtration medium and substantially degrade its filtration capacity. An imperative consideration for all decontamination methods, including UVGI, is the risk that they degrade the respirator material. This will reduce the ability of the mask to filter out infectious bioaerosols.

Some studies have examined the effects of UVGI on the respirator’s appearance, fit, airflow resistance, and filtration efficiency after one or three decontamination cycles and found no significant impact. However, the effects of prolonged UVGI exposure after multiple decontamination cycles are unknown. How much can a cumulative dose of UVGI respirators withstand, what damage will occur at the end, or how many times can disposable masks be decontaminated and reused?

This suggests that the upper limit for UVGI exposure during repeated disinfection cycles should be set by physical degradation of the respirator material. This should be determined by the loss of filtration capacity. For some FFR models, this could be a helpful warning: if the respirator material is significantly degraded after UVGI disinfection, the mask should be discarded.

For even more effective action, it is advisable to subject the mask to dry heating at around 60°C. This will inactivate potential infectious nuclei trapped within the filter weave as much as possible. Of course, it would be desirable to have sufficient time and possibilities to quickly design N95 masks specifically for healthcare professionals that can be disinfected even 50 times with UV-C disinfection cycles in less than 60 seconds. However, the current situation makes this operation impractical.


Based on feedback from our sales network, UV-BOX has proven effective in treating masks and all material contained in an ambulance during the current Covid-19 emergency.

Due to the need to transport patients and the short time between calls, Leiden University Medical Center decided to treat potentially contaminated material with our UV system. An indicator that changes color when sufficient UV radiation is achieved to inactivate the surface pathogens was used to confirm the correctness of the treatment.

Besides masks, our UV-BOX can be used to treat any other tool, such as instruments commonly used in hospitals, clinics, ambulances, etc. Light Progress also designed a specific device for stethoscope decontamination using innovative UV-C LED, a medical device class I, CE registered with the Ministry of Health, FDA approved. Healthcare environments have always been protected from possible contamination with Light Progress products. Everybody should be aware that at this time of absolute global crisis, UVGI technology can make a difference in how we control contamination spread, safeguarding patients’ and workers’ health.

UVGI technology creates no resistance in microorganisms to ensure constant efficacy and excellent effectiveness, proven by science. Many applications are possible, not only in healthcare environments. Visit our website for more information. The COVID-19 emergency requires the commitment of everyone. Light Progress is willing to provide its products at discounted prices to meet the market’s growing demands and contribute during this time of extreme difficulties.


Lindsley WG, Martin SB Jr, Thewlis RE, et al. Effects of Ultraviolet Germicidal Irradiation (UVGI) on N95 Respirator Filtration Performance and Structural Integrity. J Occup Environ Hyg. 2015;12(8):509–517. doi:10.1080/15459624.2015.1018518 Ultraviolet germicidal irradiation of influenza-contaminated N95 filtering facepiece respirators” Mills, Devin et al. American Journal of Infection Control, Volume 46, Issue 7, e49 – e55 Kowalski, Wladyslaw. (2020). 2020 COVID-19 Coronavirus Ultraviolet Susceptibility. 10.13140/RG.2.2.22803.22566. Hang L, Yang Y-R, Zhang Z, Lin Z. (2020). Genomic variations of COVID-19 suggest multiple outbreak sources of transmission. medRIX (preprint). 20. Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, Zhao X, Huang B, Shi W, Lu R and others. (2020). “A Novel Coronavirus from Patients with Pneumonia in China”, 2019. N Engl J Med 382,727-733. Hang L, Yang Y-R, Zhang Z, Lin Z. (2020). “Genomic variations of COVID-19 suggest multiple outbreak sources of transmission.” medRIX (preprint).

Light Progress takes no responsibility for mask degradation using our UVGI systems; all products must be used consciously.


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

  • UV-A (315-400 nm) with tanning properties;
  • UV-B (280-315 nm) con proprietà terapeutiche e di sintesi della vitamina “D”;
  • UV-C (100-280 nm) with germicidal properties.

UV rays are eco-friendly. Bacteria, viruses, spores, fungi, molds, 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. When using ordinary disinfectants, environmental pollution is inevitable.

They also carry severe risks from the direct inhalation of vapors 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.

They can be programmed to maintain the same level of disinfection day and night, ensuring ideal hygiene conditions 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 standard bulb replacement. These robust 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 (100-280 nm) have a robust germicidal effect and reach their maximum efficacy at the 265 nm wavelength. The germicidal effect of UV-C radiation covers bacteria, viruses, spores, fungi, molds, and mites; this is mainly due to the destructive impact of the UV-C rays on their DNA, which damages their reproductive system and prevents them from replicating.

These lamps have an emission of around 90% over the 253.7 nm wavelength. This frequency is invisible to the human eye and has solid germicidal power. The remaining 10% of the lamp’s emission is visible (typically appearing as a blueish light).

Yes, UV-C rays are found in nature as they are generated by the sun, but the ozone layer in the atmosphere acts as a shield that stops them from reaching the earth’s surface.

Legal limits for microbiological contamination of drinking water are very stringent under Legislative Decree 31/2011. Water can be treated chemically by chlorination or physically by UV-C rays and heat to eliminate microorganisms. Initially, ingested water may contain dangerous residual contaminants derived from chlorine, such as chloramines, which alter the taste and smell of water, or by-products harmful to human health and the environment, such as inorganic substances, which contribute to trihalomethane, which is highly carcinogenic. It may be possible to avoid the problems mentioned above by heating the water before use, but it is not practical and would require long cooling times to solve.

By irradiating microorganisms with a much higher dose than the minimum safety dose, a UV-C ray device installed on the pipe near the point of use of the water can safely eliminate all microorganisms. Systems and spare parts (lamps) are very inexpensive to buy and maintain. When chlorine and derivatives are present, UV-C rays reduce them to elementary particles that are harmless to humans.

When you turn on a UV-C lamp you get a strong reduction in the microbes present in the ambient air and on the surfaces reached by the UV rays. The device reduces Bacillus, Coli, Clostridium, Legionella, Vibrio, Salmonella, Listeria, Pseudomonas, Staphylococcus, Streptococcus Bacteria by 99% in a matter of minutes if placed three meters from it. This feature also allows you to intervene in areas otherwise unreachable by solid bodies such as objects and cleaning and disinfectant products. Although chemical disinfectants are mandatory, irradiating surfaces avoids shaded areas, does not generate resistant species and can be used day or night (in the absence of people), preventing rapid recontamination of surfaces and ensuring that they are always in optimal microbiological condition.

UV-C rays are used every day, primarily in:

Food and pharmaceutical industries disinfect the air and surfaces of production environments and disinfect product containers (packaging), to isolate “protected” areas for the production and packaging of products, such as clean rooms, from areas at risk of contamination. These actions significantly increase the safety and shelf life of the products we buy, with numerous benefits to our health given that they do not leave any residue and allow the elimination or reduction of chemical disinfectants, which on the contrary, may leave hazardous residue on the products.

Hospitals, to avoid the transmission, and therefore contagion of dangerous bacteria or viruses that may be found in their air or transmitted by contact between the sick and visitors.

Water treatment systems provide drinking water for humans and animals and for healthcare use to eliminate all microorganisms that might be found in water from wells, tanks, and aqueducts. This system is mandatory downstream of a carbon-activated filter, for example, in water dispensers, which are becoming increasingly popular in cities.

There are no limits to the possible applications of UV-C light; even in domestic environments, it is used to prevent mold formation on walls, eliminate mites from the bedroom, keep the indoor air healthy, and treat water.

UV-C light can also eliminate odors and grease deposits in industrial kitchens and restaurants, assisted by ozone emission. Light Progress has developed a specific system also for this type of application.

Bacteria, viruses, spores, fungi, molds, and mites are all sensitive to and eliminated by UV-C radiation.

Each bacterium, virus, yeast, mold, or mite requires a different UV-C dose to be deactivated or eliminated. There are widely recognized 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, mold, animal waste, mites, and pollen are among the leading causes of dangerous infections and allergies. Each contaminant is dispersed differently: mites, spores, bacteria, and mold, 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 design, which is dark and moist, becomes a breeding ground for them to grow and multiply, making the air we breathe unsafe.

The air also contains concentrations of dangerous chemical pollutants if inhaled in large quantities or continuously. Irradiating air in a central system or installing an air purifier complete with UV-C lamps and a TiOx titanium dioxide filter dramatically 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 ascertained through microbiological analyses or simple swab tests used to identify the presence of microorganisms on the tested surfaces. To verify the same microbial load on surfaces, in the air, and in water, before and after the treatment, it is necessary to carry out lab tests such as those for HACCP. For chemical disinfectants, producers need to provide tests declaring their disinfectant capacity; Light Progress has similarly carried out necessary tests in university labs and at private accredited bodies. Of course, for chemical disinfectants and UVGI technology to obtain the same laboratory results, the products must comply with the instructions for use.

UV-C rays cannot penetrate solid bodies, unlike ionizing radiation such as x-rays and gamma rays, which are highly dangerous to humans, even at low doses. To eliminate microorganisms using UV-C rays, they must be present on the surface of an object or transported by the air.


Significantly few materials will not block the passage of the germicidal wavelength (253.7 nm, invisible), including quartz and certain plastics such as PE or tetrafluoro-derivatives, but only if these are just a few microbes thick.

Regular window glass, polycarbonate, and other transparent materials through which it is possible to see the bluish light of UV-C lights completely nullify their germicidal effect, acting as a screen.


Continuous irradiation of the eyes and skin could cause erythema and conjunctivitis, which generally clear up in a few hours. In any case, it is sensible to avoid direct, close-up exposure to sources of UV-C rays, even for short periods. To prevent direct exposure, cover the area to be protected using any material that is not transparent to visible light (cotton or woolen clothing or overalls) or glass or transparent plastics (masks, helmets, glasses, etc.).


Yes. Light Progress offers two solutions in a unique plastic material: Uvlon Frame and Uvlon Pipe. Uvlon Frame is made from a film attached to the device and collects fragments from breakage. Uvlon Pipe is a casing thermally applied to the UV-C tube in the factory, which increases its mechanical strength (car windscreen effect) and collects and retains any broken fragments inside.


UV-C rays are similar to solar rays but do not transmit heat. However, like solar rays, they tend to have a yellowing effect on plastics exposed for extended periods (mainly white plastics).

Bacteria, Viruses, Spores, Fungi, Mold, and Mites are all sensitive to, and can therefore be eliminated with, UV-C light. Microbes cannot acquire resistance to UV-C light, unlike that which occurs using chemical disinfectants and antibiotics. UV rays are ecological. Polluting the environment is inevitable using normal disinfectants. Directly inhaling the vapors, or swallowing food products contaminated by any contact with said chemical disinfectants, can also give rise to a number of serious risks. In cases where chemical disinfectants cannot be eliminated (food, pharmaceutical, healthcare industries, etc.), using ultraviolet rays for disinfection allows a reduction in their use, with considerable economic savings and greater care for the environment, while maintaining and almost always improving the level of disinfection. UV-C light devices can be installed in environments and on machinery and be programmed to maintain the same level of disinfection day and night, guaranteeing ideal hygiene conditions, without highs and lows. On the contrary, chemical disinfectants are effective only during their actual use. Using LIGHT PROGRESS equipped luminaires, operating costs are negligible; it could be said that “LIGHT PROGRESS” UV-C systems do not require maintenance except for the normal replacement of the lamps. The cost/benefit ratio is considered excellent; the devices are both powerful and long-lasting. Hence the elimination of germs using UV-C technology is low-cost and highly effective compared to (or in combination with) other systems.

UV-C light genuinely works if properly applied and with the necessary precautions. The difference between a quality project, and an application that fails to bring the desired results, lies in the degree of knowledge about the subject, and level of experience acquired over time. Light Progress has been developing successful projects worldwide since 1987, and has built a client portfolio consisting of important companies in all fields requiring certified hygienic conditions to produce quality products and services.