top of page

UVC-HVAC Disinfection System


PROTECTION against Viruses


Ultraviolet UV-C energy and recycled HVAC air

The World Health Organization recently backed away from its stance that indoor transmission of most viruses was rare and largely confined to medical procedures like administering a ventilator.

Aerosols, particles suspended in a gas and ranging in size, are generated when we’re speaking loudly, talking, singing, and doing other activities that release particles from our respiratory tract through our mouths.  These can then be inhaled by others.

When these particles are released, they can evaporate or be transformed up and away from the body, become airborne and move about an indoor environment for a time period of minutes to hours.

This is the perfect recipe for transmission of the coronavirus if the particles are trapped indoors with poor ventilation in recycled air - such as with most commercial HVAC systems in large buildings.   Building occupants are breathing a higher percentage of the same air that other people are exhaling.  If someone inside the building is shedding a virus, it can build up in the recycled air.

As well as the HVAC system being very efficient at pushing potentially dirty air around a building, it also provides drier air which viruses prefer.

Studies are also showing that genetic material from many different viruses, is being discovered inside the HVAC system with the surface of the cooling coil being an excellent growth medium owing to the biofilm that collects on it. 

Given Thailand’s extreme temperatures and humidity levels, this problem is magnified as outdoor air being mixed with the cool recycled air is generally kept to a minimum for cost savings.  Not to mention the risk of PM2.5, which is becoming more of a problem in addition to sick building syndrome, mold, and viruses, attributed to Thailand's tropical climate.

How does the Ultraviolet UV-C HVAC system work?


1.  Over time the surface of any evaporator coil will attract a biofilm of microorganisms, mold, pathogens and other contaminants.  No matter how often a traditional cleaning program is used, this process is unavoidable.

Pathogens and airborne contaminants are then distributed throughout the HVAC system.

2.  Installation of the UVC-HVAC Infection Control Barrier begins to work the moment the system's powerful Philips UV-C tubes are switched on.

Immediate benefits of a clean evaporator coil are an increased heat transfer, enhanced airflow and a significant reduction in airborne contaminants.

3.  Approximately 21 days after installation, 99%+ of the biofilm that was living on the surface of the coil is killed by the UV-C energy.  New contaminants cannot begin to grow whilst the Philips UV-C tubes are in operation.

Contaminants which are killed by the UV-C energy are 'washed away' by the condensate water.

Overview of the UV-C HVAC System

Poor indoor environments influence the health, performance and safety of occupants.  Many existing ventilation systems have dirty and fouled cooling coils, drain pans and plenums that have been subjected to the growth of pathogens including, viruses, bacteria, yeasts and molds.  Air passing over dirty coils, drain pans and plenums is likely to be contaminated and could fail to provide adequate indoor air quality - especially important in healthcare settings.  This can be especially troublesome for allergy sufferers.

Microorganism and pathogen growth can also increase air-flow resistance, and reduce heat transfer, lowering the capacity and efficiency of the cooling system.  Manually cleaning the cooling coils is a laborious process that only temporarily removes contaminants.

Using our range of modular UV-C systems, with the UV energy being produced by Philips lamps designed specifically for this purpose, provides continuous, cost-effective protection against the spread of airborne pathogens that easily grow on the cooling coil’s surface.

Expensive HEPA filtration has long-been an essential for healthcare facilities, and effective in trapping dust, pollen and other particles but it is the wet surface of the cooling coil that becomes the major incubation site for harmful pathogens.  Filtration alone cannot combat this risk.

Currently in use in medical facilities in Bangkok, our UVC-HVAC system has proven successful at removing 99.99%+ of surface contaminants on the cooling coil surface.  Measurements were taken using the Hygiena SystemSure swabbing unit before and after installation and witnessed by engineering management of the facility.

Another benefit of the UVC-HVAC system is the ability to return the cooling coil to it’s original design specifications.  Years of neglect with regard to cleaning the coil results in a gradual decrease in the effectiveness of the coil to adequately ‘condition’ the air.  Even after a short period of 21 days, the UVC-HVAC system will remove 99.99%+ of biofilm (the layer of ‘slime’ containing mold, microorganisms and pathogens) allowing more humidity to be removed from the air on each pass made over the coil.

As well as providing lethal doses of UV-C to the pathogens on the coil’s surface, once the aluminium surface of the coil is returned to it’s original state of cleanliness it can begin to attack the problem of humidity experienced in SE Asia and lower the Dew Point, allowing building occupants to breathe ‘fresher’ air.

With the Philips tube life of 9,000 hours, engineers no longer need to schedule cleaning as the UVC-HVAC system is working 24/7 on their behalf.

bottom of page