KillVir – UV-C Air Disinfection
Equipment for air disinfection by UV-C radiation …
- immediate elimination of pathogenic microorganisms by passage through the device
- unrestricted presence of people
- effective against SARS-CoV-2 and its mutations
- contaminated air passes close to the UV-C lamps to ensure a high dose of radiation for effective elimination of pathogenic microorganisms
- powerful fans for efficient room air circulation
- UV-C tube operating hours counter
- UV-C tube life 18,000 operating hours
- dust filter to maintain good efficiency
- stainless steel design
- visor for checking UV-C lamps during operation
- placement under a ceiling,on a wall, or on our stand
Protect your employees, customers, clients and yourself from viruses, bacteria, fungi and other unwanted microorganisms. Offices, meeting rooms, waiting rooms, receptions, workshops, retirement homes, schools, etc.
Aeroterm “KillVir” is intended for effective disinfection of indoor air where people are or may be present. The device eliminates or inactivates microbes floating in the air in aerosols or on dust particles. The treated air is spirally flowed through a long closed area in which powerful UV-C tubes are placed longitudinally. These tubes do not produce toxic ozone, which can otherwise be generated during the work of UV sources. All internal parts of the device have good reflectivity for UV radiation. All of these factors maximize the radiation density and exposure time, and therefore the dose of UV-C energy that the particles receive in a single pass through the instrument.
Powerful, noise insulated fans transport air along the tubes snd also mix the air in the room. Thus, the disinfecting effect is not limited to the surroundings of the device itself. On the stand, the device can be easily and quickly moved to different areas, where disinfection can be started immediately.
Germicidal Effects of UV-C Radiation
The resistance of microorganisms to UV-C radiation is the subject of scientific analysis and measurement. From their outputs, it is possible to determine the dose of UV-C energy that the species must receive in order for inactivation. We processed these data for selected types of microorganisms in a table which can be found in the product datasheet below. The energy dose for 90%, 99% or 99.9% inactivation is reported here.
|Microorganism||H90 [J/m2]||H99 [J/m2]||H99,9 [J/m2]|
H represents the dose of UV-C energy required for 90%, 99% and 99.9% inactivation of the microorganism
Resistance of Microorganisms
Resistance of microorganisms to the germicidal effects of UV-C radiation as described above. For disinfection efficiency estimation, it is important to know both the dose for inactivation of individual pathogens and the amount of UV-C energy that the device provides per pass. This dose can be found for KillVir instruments in the table of technical parameters below.
The type of room (volume, shape and purpose) is also important. The volume is important for selecting the fan power. We follow the principle that the air in the room should be mixed in a maximum of 1-2 hours. Too low fan power also causes imperfect air mixing and only local efficiency of the device. That is why we do not offer such weak fans. It may be better to use several weaker devices in fragmented areas. The device can be hung under the ceiling, mounted on a wall or on a mobile stand on wheels.
Choosing the Right Type
HIGH RISK: places with a highly probable occurrence of pathogens – medical facilities, surgeries, dental surgeries, laboratories, waiting rooms…
MEDIUM RISK: places with frequent presence of people – canteens, snack areas, meeting rooms, schools, open office…
LOW RISK RATE: places with a low frequency of other people – offices for individuals, apartments…
TYPICAL ROOM SIZES: (with a standard ceiling height of 2.5m)
|Type||UV-C Lamps||H [J/m2]||Qv [m3/h]||Noise [dB(A)]||Dimensions [mm]||Weight [kg]|
|Type||UV-C Lamps||H [J/m2]||Qv [m3/h]|
|Type||Noise [dB (A)]||Dimensions [mm]||Weight [kg]|
|Type||Noise [dB (A)]|
H represents the dose of UV-C energy provided in one pass through the device
Qv represents the real air flow through the device in 1 hour – it is recommended that the device changes the air in the room in a maximum of 1-2 hours
What is ultraviolet germicidal radiation?
This is a disinfection method that uses ultraviolet (UV) radiation with a short wavelength of 200 – 280nm (this area is referred to as UV-C) to inactivate or kill pathogenic microorganisms. It can be used to disinfect surfaces, air and water.
What dose of UV-C energy is required to kill or inactivate the SARS-CoV-2 virus causing COVID-19?
This virus is so new that more of this data has not yet been published. However, we found the first results of work in this field from Italy, the USA and the Netherlands. A summary of their results is given in a clear table. Values for influenza virus and tuberculosis bacteria are given for comparison:
|Pathogen||H90 [J/m2]||H99 [J/m2]|
H90 (H99) – the dose of UV-C energy required for 90% (99%) inactivation of the
However, some well-known similar viruses from the SARS family need values up to 2.6 times higher than the SARS-CoV-2 virus. More detailed tables for other pathogenic microorganisms can be found in the Aeroterm KillVir Datasheet or web page.
What parameters should the disinfection device have and how to choose it?
First of all, it is necessary to determine which microorganisms we want to eliminate and with what percentage of efficiency (for table data, see eg the Aeroterm KillVir Datasheet or web page). It is necessary to take into account the nature of the room (office, waiting room, dental office…). Microbiological pollution is brought by people and animals – it is therefore necessary to consider their number, density, number of arrivals. Accordingly, determine by which reserve to increase the selected required dose of UV-C energy. Indeed, the minimum reserve should be 20% to reduce the efficiency by dusting UV emitters and 10% to reduce the efficiency of UV-C emitters at the end of their service life. The device is then selected according to the minimum amount of UV-C energy thus determined and increased. The disinfection device must provide this necessary increased amount of UV-C energy, – ie. a dose equal to or greater than the indicated dose for the pathogen per pass of air through the device. Every manufacturer or retailer must state these essential parameters. Of course, there are also a number of products on the market whose effect is undefined, and this absence is being replaced by massive advertising and strong expression.
We decided to eliminate not only the SARS-CoV-2 virus, but also, with 99% efficiency, the influenza virus, which will attack us in various mutations even after the pandemic subsides. Influenza viruses are more resistant than SARS-CoV-2 and a dose of UV-C energy H99 = 72J/m2 is required for their 99% elimination. If we consider a reserve of 50% (30%), we will require the disinfection device to provide a dose of UV-C energy E = 72×1.5 = 108J/m2 (94J/m2). This corresponds to the Aeroterm KillVir HB475 device with a dose of H = 127J/m2 (suitable for large rooms) or the Aeroterm KillVir LS430 type, which provides a UV-C energy dose of H = 115J/m2 (suitable for smaller rooms).
How to choose a device for a given room size?
A very important function of the disinfection device is to be able to move the air in the room so that the desired air circulation occurs throughout the room and not only in the immediate vicinity of the device.
For example, the air in a smaller room 6x4x2.6m, whose volume is 62.4m3, weighs about 75kg. These facts require that the device be equipped with a powerful fan unit. The optimal condition is that the volume of the room is pumped by the device within 1 hour, the worst within 2 hours. The sooner, the faster the disinfection effect starts. This corresponds to the fact that for a given device, the optimal room size is up to the value of the stated actual air flow through the device (some manufacturers state the nominal fan flow, but the actual flow is significantly lower). However, it must always be the case that the device must emit a sufficient dose of UV-C energy to inactivate the pathogen. For larger rooms and complicated rooms, more devices can be purchased. For rooms with high risk and frequent door opening frequency, it is necessary to choose a device with the highest possible air flow.
Aeroterm KillVir LS475 device with UV-C energy dose H = 127J/m2 and air flow through the device Qv = 187m3/h or eg Aeroterm KillVir LS430, with UV-C energy dose H = 115J / m2 and flow Qv = 96m3/h can be used for 99% elimination of influenza virus. These devices provide a similar dose of UV-C energy, but differ in the value of the air flow through the device. Type HB475 is therefore optimal to use in rooms up to 187m3 (11x6x3m), type LS430 in rooms up to 96m3 (7x5x2.7m).
How should I use the KillVir disinfection device? Is a shorter time enough or should it be switched on all the time?
The KillVir UV-C disinfection device has the unique advantage that it can work even in the presence of people and thus continuously reduce the amount of pathogens in the room. The device can be operated continuously, 24 hours a day for 18,000 operating hours (approx. 2 years). Then the UV-C tubes need to be replaced. If you need to move to different rooms and try to keep it in the room in the shortest possible time, it is necessary to remember that the air in the room has to be put in motion and circulate for a while. We recommend a minimum of 2 hours for a room that has a volume less than or equal to the flow rate of the particular model. In larger rooms, up to twice that time. In general, however, it is best to have the disinfection device switched on while people are in the room and ideally for at least an hour afterwards in order to continuously disinfect the air. Otherwise, the microbiological load would continue to increase. This should be supplemented by disinfecting the surfaces (by wiping the surfaces with a disinfectant solution, etc.).
What is the main advantage of this method of disinfection? What makes this method other than disinfecting with ozone or spraying disinfectant solutions?
KillVir UV-C air disinfection is unique in that it works in the presence of people and continuously spraying disinfectant solutions must not be used in the presence of persons (there is a risk of reduces the microbiological load in the room. Conversely, disinfection with ozone or by poisoning and other health risks) and must therefore be applied only after all-day operation. During operation, however, there is a continuous increase in the microbiological load in the room to which people are exposed inside. Chemicals or ozone also act on surfaces, but they can also have degrading effects. In terms of different effects and application time, these methods can effectively complement each other.
What are the competitive advantages of Aeroterm KillVir devices?
- highest UV-C performance, efficiency and durability
- the values of the UV-C energy doses provided by the individual types of the device and the doses needed to inactivate the individual pathogens are given, so the appropriate type can be chosen exactly
- immediate elimination of pathogenic microorganisms as they pass through the device
- unrestricted presence of persons
- absence of contaminated waste
- tight passage of contaminated air around UV-C lamps ensures a high dose
irradiation for the effective elimination of pathogenic microorganisms
- powerful fans for efficient room air circulation
- made from premium Philips components, UV-C tube life 18,000 operating hours (approx. 2 years of continuous operation)
- the dust filter prevents contamination of the internal reflecting surfaces of the device and thus of sagging
- all-stainless steel design – representative appearance and easy cleaning
In which units are the parameters of the disinfection devices given? How are watts and joules related?
Watt is a unit of power, ie the amount of energy delivered per unit of time. The joule is a unit of the amount of energy. For disinfection purposes, their density is decisive, so it is necessary to apply them to an area of 1 m2. The radiation power incident per 1 m2 is called the radiation density E and its unit is W / m2. The energy of radiation that fell during the exposure time t per 1m2 is called the dose H. It is the product of the radiation density E and the exposure time t, ie:
H = E x t,
The dose has the unit Ws/m2 = J/m2.
When disinfecting with UV-C radiation, it should of course be the energy radiated in the UV-C region. Conventional UV-C emitters in this area emit approximately 1/3 of their total power!
What about ozone formation during the operation of UV emitters and what about ozone at all, because it is also used for disinfection?
Ozone is a highly reactive gas (a strong oxidant). It is naturally found in the high layers of the atmosphere, where it protects us from the penetration of UV-C radiation from the sun. In the ground layers of the atmosphere, it is created when the sun’s rays shine into the air air polluted by human activity. However, its stability is low, its lifespan is in units of seconds and it decomposes into normal oxygen. However, new ozone molecules are still being formed under suitable conditions. In the indoors conditions, this is an undesirable immission because it is harmful to human health.
With sufficient concentration, it kills all microorganisms, so it is also used for disinfection. During this disinfection, the presence of people is excluded and the room must then be thoroughly ventilated. The corrosive effects of ozone must also be taken into account.
Ozone is generally produced when UV emitters work. It causes UV radiation with wavelengths below 240 nm. The extent to which these wavelengths can be filtered out (special types of glass, filters…), the extent to which the formation of ozone by UV sources is suppressed. For UV-C tubes used in AEROTERM’s KillVir, the ozone concentration is below the limit of quantification.