Air conditioning systems, fans? No! Air cleaners!
Which devices really provide protection from virulent accumulations of aerosol in the room air?
Do fans or air conditioners enhance the distribution of droplets and aerosols in the room?
Not only in times of Corona, dangerous superficial knowledge, untruths and recommendations about air conditioners and air cleaners spread like a wildfire in social media. Air conditioners are blamed to be virus spreaders. And simple fans are hyped to provide protection from infectious aerosols in the air. No matter whether the window is open or closed. What is right? What do you need to know about air conditioners and fans with regard to Corona virus?
How are room air and the Corona virus linked with each other?
Virologists agree with each other: The Corona virus mainly spreads by breathing, only a small amount is distributed by smear and droplet infections. When breathing through the mouth and when talking, thousands of aerosols – tiniest particles of saliva – are emitted into the room.
These particles are invisible to the naked eye. They spread further than the recommended minimum distance of 1.5 - 2.0 m, remaining in the room air for several hours. If a person is infected, these floating particles are contaminated with viruses or bacteria. If infectious aerosols are inhaled, viruses deeply penetrate the pulmonary alveoli via the respiratory tract.
Respiratory masks with particle filter offer protection from aerosols in closed rooms, as well as high-frequency air cleaners as the TAC V+ from Trotec. However, protective masks do not protect from inhaling infectious aerosols. They only keep away large droplets.
Are inside and outside air equally dangerous?
Outdoors, aerosols emitted when talking are distributed and diluted by natural air movements. For this reason, the risk of inhaling other people’s aerosols when they talk is relatively small. However, in closed rooms with no air exchange, the concentration of aerosols increases with every additional person. Undiluted accumulations of aerosols float throughout the room, and the danger of inhaling infectious viruses from the air is comparatively high.
How does an air conditioning system affect the danger of infection?
Air recirculation devices only cool down the room air, but there is no fresh air supply from outside. Besides, commercially available air conditioning systems are not equipped with a special HEPA filter – which is part of the air cleaner TAC V+ or TES 200 with H14 HEPA filter that allows to filter airborne viruses or bacteria. Present viruses in the room air are extensively distributed in the room air with the air flow. This is why “virus spreader” is a word.
- Air conditioning systems with air recirculation do not offer protection against viruses such as the Corona or influenza virus. Accumulations of aerosol are not diluted or filtered out.
- Aerosols carrying viruses are distributed through the blown-out air of the air conditioning system into the farthest corner of the house. Even if you stick to the distancing regulations, you'll inhale the aerosols.
Does a fan protect from an infection if the window is open?
Some virologists recommend placing a fan in front of the open window to transport the germ-laden room air to the outside.
In theory, this is right. The air current produced by the fan sucks in room air and blows viruses out of the window. In practice, however, this is quite unrealistic! In summer, an open window with the fan switched on may be quite pleasant.
But what do you do in winter, when it's freezing outside with temperatures below zero? And how are you able to concentrate on your work in the office, if traffic noise booms through the open window? In retirement homes and treatment centres, it cannot be recommended either. Elderly people in retirement homes have an increased need for warmth. An open window may have severe consequences.
- Indeed, a fan in front of an open window does reduce the risk of infection. The reason for this is the dilution effect which results from the fresh wind of outside air.
- However, this kind of protection from infection is not quite practical and cannot be realised in the cold season and for older people.
- If the outside temperature is equal to the inside temperature, the outside air cannot flow into the room.
Does a fan protect from an infection if the window is closed?
In closed rooms, a fan provides the same infection protection as an air conditioning system with air recirculation. No protection at all! Without a supply of fresh air from outside, the room air will be merely moved, but not diluted. Moreover, fans don't provide any kind of filtering effect.
- Therefore, a fan in a closed room does not provide protection from Corona virus. Accumulations of aerosol are not diluted or filtered out.
- The opposite is true! Aerosols carrying viruses are distributed through the blown-out air of the fan into the farthest corner of the house. Even if you stick to the distancing regulations, you'll inhale the aerosols.
How reasonable is cross-ventilation in terms of protection against infections?
Cross-ventilation will always allow air changes in the room. The air contaminated with germs is drawn to the outside and fresh air flows into the room. However, airing rooms like this always carries risks. Infectious aerosols always spread through the entire room before they escape to the outside, especially in offices or restaurants where many people stay. All persons remaining in the air current will inevitably inhale these aerosols.
An efficient protection against viruses in the room air can only be provided by a high-frequency air cleaner, such as the TAC V+ that offers HEPA filtration and high air flow rates
The mobile air cleaner TAC V+ purifies room air as effectively as air purification is carried out in hygiene-sensitive hospital operation theatres.
Made possible by the extremely high air flow rate and the innovative H14 HEPA virus filter. The room air is sucked in near the ground, cleaned from bacteria and viruses by means of the HEPA filter and finally released into the room as germ-free air.
Depending on the room size, the room air is circulated and cleaned up to 20 times per hour. The result is that suddenly occurring accumulations of aerosol are diluted with clean air in the area of your head to such an extent that the virus load and risk of infection will be remarkably reduced!
No installation, no complicated connection. Simply plug in and provide for the maximum infection protection possible!
Learn more about the technical possibilities of virus air filtration
You want to know which technical aids offer effective protection against viruses in the room air? Do you have any questions with regard to the different cleaning methods offered on the market, their functional principle and their suitability for virus filtration? Visit our air cleaner-FAQ for virus filtration – Here you'll find answers to all of your questions with regard to air purification, virus filtration, standards as well as filter classes and of course the high-performance air purifier TAC V+ ...
High-frequency air purification protects both personnel and patients
If the room air is kept free from germs and viruses, the airborne risk of infection will be minimised likewise. Trotec high-frequency air cleaners such as the TAC V+ are exactly designed to perform this task for they efficiently and quickly reduce the intensity and time aerosol accumulations and suspended matter stay in closed rooms, creating zones with an extraordinarily reduced risk of infection for both patients and personnel.
Directly at the installation site, the mobile air cleaner TAC V+ creates a “clean zone area”, flooded with purified air and filtered from viruses. Within this zone, the surrounding air nearly completely stays free of airborne germs and viruses because the TAC V+ is able to take in large volumes of contaminated room air and to carry out effective H14 HEPA filtration. Moreover, the device is able to purify room air zones in a flexibly adjustable manner with clean air that has been filtered from viruses and aerosol particles.
Effective against bacteria and virus accumulations
Trotec high-frequency air cleaners are equipped with HEPA filters of class H14 which filter out more than 99.995 % of all fine suspended particles larger than 0.1 µm with a transmittance of only 0.005 %. Or in other words: No more than five of 100,000 particles pass the H14 filter. Thanks to this unique feature, these kinds of high-performance filters are also used in operation theatres or comparable hygienically sensitive areas in order to produce clean air. This way, you create optimum conditions to keep room air and breathing air in waiting and treatment rooms free from germs and viruses in times of spreading epidemics.
Well-known viral strains such as SARS-CoV or MERS-CoV have a particle size of 0.005 to 0.1 µm. Most of the time, they form accumulations with other particles (such as saliva or suspended matter) which increases their size up to 0.4 µm or 0.5 µm. These accumulations are referred to as germs and will be filtered out reliably by the Trotec H14 air cleaning filters.
All H14 HEPA filters by Trotec fulfil the highest quality standards that are obligatory for bacteria and virus filtration.
- Each H14 high-performance filter is tested individually and is assigned its respective serial number
- The test report is enclosed as certificate in duplicate with each H14 filter
- The original test certificate can be filed with the documents for the device. If required, the copy can be attached to the air cleaning device.
- HEPA high-performance H14 filters are tested in compliance with EN 1822 and EN 60335-2-69.
Also suitable for any TAC air cleaner with H13 filter
You can also insert a H14 HEPA filter by Trotec into your TAC air cleaner if you already possess a TAC device. The H14 filters are available as an accessory, e.g. for the professional air cleaners TAC 3000, TAC 5000 or TAC 6500. Simply replace the H13 filter in the filter compartment with a H14 HEPA filter.
The TAC V+ puts things into motion – an exceptional amount of virus-free clean air, satisfied customers and various media
In our media library for the TAC V+ you'll find some videos explaining the functional principle of the TAC V+ and its effective principle of air purification. In addition, we have compiled a large variety of different information videos describing the use of the TAC V+ in different fields of application like restaurants, supermarkets or fitness studios. Furthermore the TAC V+ media library will provide you with recommendation videos by satisfied users and with a selection of different media reports about the air cleaner TAC V+. Come and see for yourself ...
With the TAC, it's not just the individual details that set standards – it's also the sum of all details
High mobility – extreme versatility – large clean air capacity – high-performance filtration – filter decontamination and regeneration – value-for-money ratio
Well thought out to a detailed level, unparalleled in its entirety: With these plus points, the TAC V+ – as is scientifically proven in several studies – ensures a technically effective and highly versatile solution to reduce the risk of infection by aerosols in closed rooms.
Stable, but not stationary: mobile virus protection, flexibly applicable exactly where protection is needed
The TAC is flexible, mobile and can be used anywhere at any time
The extremely stable, robust and scratch-resistant metal housing was specially designed for the use in environments where many people come together, work, play, learn or celebrate. This makes it possible to use the TAC V+ high-performance air purifiers without any installation effort anywhere they're needed.
In a flexible, mobile and modular fashion, the exact number of TAC air cleaners as requested by the hygiene concept can be provided, variably adapted to the occupancy, circulation rates, background noise, room size and room geometry.
Mobility – more than just an attribute: easy set-up and moving instead of cumbersome set-up and conversion
Large, conventional floor-mounted appliances have one decisive disadvantage: they are large, heavy and usually have to be set up on site. Once set up, they remain at their place of use and can only be relocated with great difficulty – in other words, stationary floor-mounted appliances. The TAC V+ and its model variants are cleverly designed: Thanks to their carriage design, they are both mobile and stable at the same time! This high degree of mobility of the TAC gives you the flexibility you need at any time.
If, for example, classrooms, offices, studios or other rooms need to be moved, then the TAC V+ high-performance air purifier can be easily repositioned – or completely relocated to other rooms. Or if for school parties, in theatre groups, club and company celebrations or other events, a higher clean air volume is temporarily required to ensure air exchange due to the larger rooms and large number of people.
The framework conditions can change constantly and effective hygiene concepts therefore require a high degree of flexibility in daily implementation. That's why you can also reposition the TAC extremely flexibly – because the TAC is a true mobile device with large wheels and a push handle allowing it to be moved around without any problems. Always exactly where protection is needed.
High versatility due to individually adjustable air volumes
Another decisive advantage of the TAC is the air volume that can be individually adjusted to the room volume and desired circulation rate. Regardless of the room size or application requirements, the correct and permanently constant volume flow is always available at the touch of a button for additional safety.
Large clean air capacity, high flow pressure and an optimum flow geometry
TAC high-performance air purifiers have "the power to quickly dilute the room air"
Time is the most important factor for reducing the indirect risk of infection. And we're talking about the shortest time possible for quickly and effectively diluting the infectious aerosol accumulations that are for example generated by a super-spreader, directly at their source. This requires large volumes of clean air and a high fan performance to establish an optimized flow geometry. After all, the amount of virus-free air supplied is decisive for the occurrence of infection.
This is what the TAC high-performance air purifiers TAC V+, TAC M and TAC ECO as well as the multi air handler TAC XT offer: with a large clean air volume, an optimum flow geometry and a fan performance that is more than high enough, a circulation flow is established in the room, ensuring that the virus concentration in the room air is first diluted and is then effectively filtered with cleaned air.
Only sufficiently high circulation rates or virus-free air volumes minimize the risk of infection, this is scientifically proven. Where the effective treatment of the risks of infection by aerosol particles is concerned, high circulation rates (at least 6 times the room volume or even more, if possible) and therefore large volumes of cleaned air are indispensable — despite promises to the contrary made by other providers advertising one to three air changes per hour as sufficient.
As is proven by scientific studies, effective virus filtration requires a sufficiently dimensioned volumetric flow so as to ensure that the air cleaner can provide for the number of air changes required as is guaranteed by the TAC XT, TAC V+, TAC M and TAC ECO. In this context, "air change" does not refer to a complete exchange of the air, but to the proportion of virus-filtered clean air that is supplied, relating to the room volume per hour.
FlowMatic ensures constant air circulation rates at any power level even with increasing filter pollution
In order to comply with the circulation rate required by the hygiene concept, a constant volumetric flow throughout the whole operating lifetime is indispensable. However, the filter elements of every air cleaner are successively clogged over time by coarse and fine dust (e.g. caused by traffic load). This leads to an increasing counter-pressure combined with a strongly decreasing air flow rate, inevitably reducing the level of protection envisaged.
Just like with the cruise control of your car, the FlowMatic sensors capture the actual air flow rate values within the entire filter ladder and consecutively adapt the system performance dynamically. In this way, the air volume target value once preset remains constant at any power level! This not only increases the filter lifetime and system efficiency, but also guarantees compliance with the circulation rate required by the corresponding hygiene concept.
Air cleaners without a FlowMatic control are not able to constantly and reliably meet the requirements so as to comply with the circulation rate required. This is why the filters of such models must be checked at regular intervals and changed if necessary for safety reasons.
High-performance filtration: H14 means maximum HEPA filter efficiency
The TAC V+ can "effectively separate" viruses
Exclusively H14 HEPA high-performance filters complying with EN 1822 specifications (ISO 45H filter ISO 29463) like they are used in the TAC V+ are able to even filter the tiny virus-infected aerosol particles (0.1 - 0.2 µm) from the room air, and this at a percentage of 99.995 %. Therefore the filter efficiency of H14 HEPA filters complying with EN 1822 is 10 times higher than that of H13 HEPA filters with 99.95 %, as used in most air cleaners!
99.995 % or 99.95 %? This may not sound like a lot, but exactly these two decimal places make the big difference between H13 and H14 HEPA filters! Virus-carrying aerosol particles are extremely tiny. And "virus filters" are designed to "filter viruses". That's why the TAC V+ not only filters the large, but also the small-sized, highly infectious aerosols from the room air not even filtered out by FFP2 and FFP3 respiratory masks, which therefore don't offer genuine protection. Real safety is exclusively provided by an H14 HEPA filter (EN 1822)!
Scientific studies, however, qualify that a filter performance beneficial to the decay rate pursued can only be confirmed if the volume flow of the air cleaner and the flow speed in the particulate air filter are sufficiently attuned to one another by an adequately dimensioned filter surface, a property which is offered by the high-performance air purifiers TAC V+, TAC M and TAC ECO as well as the multi air handler TAC XT!
Thermal filter decontamination – your safety airbag
Unique technology – Trotec exclusive
Only with the TAC V+ and TAC XT the special, fully encapsulated H14 high-temperature lamellae high-efficiency particulate air filter is treated thermally at regular intervals. Explicitly for this purpose, this filter has been developed and interspersed with special, heat conducting metal fins.
This thermal filter decontamination technology offers you several benefits at the same time! By heating the filters, the proteins of the viruses filtered out, which are relevant to the infectiousness, are denatured, and the viruses are practically destroyed. Therefore infectious viruses can no longer enter the ambient air from the filter, for example by improper handling during a filter change. Furthermore, bacteria, germs and other microorganisms are additionally destroyed. Filter decontamination at temperatures much lower than 100 °C would not be sufficient here. It's not without reason that drinking water containing germs, for instance, should be boiled, i.e. heated to about 100 °C, for at least three to five minutes before use.
All this means extra employee protection can be ensured during operation and also when the filter is changed! You could say, it's the "virus airbag" that provides for more safety. It is there when you need it – and as long as nothing happens, you won't even notice it.
Scientific studies substantiate the usefulness of thermal filter decontamination for ensuring effective virus filtration. Professor Christian Kähler, for example, points out: "To ensure a maximum degree of hygiene and a longer lifetime in continuous operation, the H14 filter should be heated to approx. 100 °C every day for about 15 minutes, in order to prevent the formation of biofilms, bacteria and fungi without using harmful chemical additives or UV-C radiation."
We recommend carrying out thermal decontamination once a week. Only in hygienically sensitive areas with a low air temperature and very high humidity level should thermal decontamination be carried out once a day. Thermal decontamination of the filter carried out on a weekly basis requires only 1.0 kW of additional energy per week and will not increase the room temperature.
The decisive plus in terms of safety and hygiene for only 28 cents per day, which moreover pay for themselves
The on-demand thermal filter decontamination offers the decisive plus in terms of safety and filter hygiene, while the additional energy input required is negligible. Even with thermal decontamination carried out daily, the costs only amount to 1 kWh, i.e. 28 cents per day of use. And if thermal decontamination is carried out once a week, the costs are just under €15 per year.
Because thermal decontamination also increases the filter lifetime, a new filter has to be purchased less frequently. This saving means that you benefit from the added value of thermal decontamination – maximum filter safety and filter hygiene – practically free of charge!
Thermal filter regeneration – for optimum filter hygiene and a prolonged filter lifetime
No filter humidity, no filter mould or odour, and at the same time a much longer filter lifetime
Aerosol separators and virus air cleaners take effect where many people are present in narrow spaces over a longer time and exhale larger quantities of aerosols. Aerosols, whether virus-carrying or not, for the greater part consist of micro droplets – pure water, that is. Customary H14 filters may be able to "catch" these humid aerosols, however, they also catch additional problems. Since the increasing humidity in the filter causes it to start fouling more quickly. As a result, the filter resistance increases, constantly reducing the clean air volume emitted and thus significantly reducing the filter lifetime. The fast fouling of filters at high loads of aerosols has been scientifically proven by field tests.
Moreover, the constantly high level of humidity favours the formation of filter mould or biofilms. Instead of eliminating a hazard, others may therefore be created. For example, a decreasing flow rate, shorter filter lifetimes and mould on the filter. But since the filter is heated to more than 100 °C at regular intervals, the ingress of moisture, fast sooting and filter mould are not a problem with the TAC V+ and TAC XT. Since the humidity is fully discharged again in the course of the thermal regeneration cycle, not only drying the filter at regular intervals, but additionally regenerating it again via its self-cleaning function.
With this innovative procedure the filter resistance remains low and the clean air flow remains at a constantly high level for a considerably longer time. Consequently the lifetime is longer than that of other filter systems without thermal regeneration and decontamination. This is also confirmed by current studies, which sum up as follows in the context of an examination of the TAC V+ and its H14 filter which complies with the specifications of EN 1822 (ISO 45H filter ISO 29463) and which features a self-cleaning function: "Therefore it is to be expected that this filter can have a lifetime of several years, depending on the load."
Maximum filter hygiene for just 28 cents per day, which practically pay for themselves
Thermal decontamination and regeneration of the filter requires only 1 kWh of energy. Even if thermal decontamination is carried out once a day, the costs amount to approx. 28 cents per day of use, and if thermal decontamination is carried out once a week, the costs amount to just under €15 per year. At the same time, however, the unique thermal filter decontamination and filter regeneration offers you the decisive added value in terms of safety and hygiene over the entire filter lifetime. And all this is basically at zero cost, because the longer filter lifetime achieved by regular thermal filter regeneration means that a new filter does not have to be purchased as often – this saving means that you benefit from the added value of thermal decontamination – maximum filter safety and filter hygiene – practically free of charge!
Low-noise: Hard to believe, hardly to be heard
The TAC V+ is an air cleaning revolution of the silent kind
The task of qualified high-performance air purifiers is to make the utilization of interior spaces possible again – and not to make it more difficult! Nevertheless, without large volumes of clean air, the risk of infection cannot be minimized!
When aerosol particles are separated or viruses and bacteria are filtered out, high air circulation rates between 6 and 8 per hour are required, and in the medical sector even 12- to 15-fold air circulation rates per hour. It is important to note that the virus-free room air volume, which determines the risk of infection, results from the circulation rate and the room volume. Without these large air circulation rates, spontaneously occurring aerosol clouds cannot be reliably and quickly diluted and filtered out.
Therefore, even in smaller rooms of 45 m² you already need amounts of clean air from 700 m³ to 1,500 m³, which requires a fan with a correspondingly high ventilation power. In particular, to establish an optimum air flow and air routing in the room. In addition to the flow geometry, filter efficiency and long filter lifetimes, however, an acceptable noise level, in spite of the large air volumes and the high fan performance, is desirable.
This is why one of the top priorities in the design of the TAC V+ was a low noise emission
For noise sensitive areas such as schools, offices or medical practices we recommend using the optional sound protection hood by means of which the sound level experienced subjectively can be again reduced by up to 50 %! In workshops, packing stations or discotheques, etc. the use of the sound protection hood usually is not required.
With an optional H14 Ultra-HighFlow filter and an installed sound protection hood, the TAC V+ for example merely generates approx. 38 dB depending on the power level. For comparison: A customary laser printer already generates a sound level of approx. 50 dB during operation.
Well thought out to the detail, unparalleled in its entirety – the advantages of the TAC V+ at a glance:
- High versatility due to mobility: Flexible, mobile and immediately usable everywhere – simply set up the TAC high-performance air purifier exactly where protection is needed. For the framework conditions and requirements can change constantly. A decisive advantage over stationary, large floor-mounted appliances.
- High versatility due to adjustable air volume: With the TAC, the air volume can be individually adjusted to the room volume and the desired circulation rate. Always the correct and permanently constant volume flow for additional safety!
- Large clean air capacity: Up to 2,200 m³/h of virus-filtered clean air with a high flow pressure for optimum air circulation and high air circulation rates.
- High-performance filtration: Fully encapsulated H14 metal lamellae high-temperature filter "made in Germany" with a flow-adapted filter surface for virus-filtered room air.
- Thermal filter decontamination: 100 °C for 100 % inactivation of viruses, bacteria and other microorganisms, for maximum filter hygiene and longer lifetimes in continuous operation!
- Thermal filter regeneration: 100 °C for 100 % evaporation of the aerosols; self-cleaning function of the filter, low filter resistance, constantly high clean air volume, exceptionally long filter lifetime, no filter mould. Approx. 50 % fewer filter changes meaning lower operating costs.
- Background noise: The most silent high-performance air purifier in relation to the air flow rate / device size.
Whether for sale or for rent: Trotec offers the right air cleaners
Whether you like to rent a high-frequency air cleaner on a short-term basis or whether you prefer buying it to benefit from a long-term use – at Trotec, devices and respective filters are always available from stock. Our expert consultants are also happy to advise you with regard to integrate your device into your AC system.
Trotec solutions do not only allow you to generate clean and purified air, but also make the quality of the room air visible!
Triple indicator for healthy room air: Our BQ air quality measuring devices indicate all important values
The Air quality monitor BQ30 should not be missing on any teacher's desk or in any open-plan office because this environmental monitoring station shows you the most important values for healthy room air at a glance: In addition to the current CO2 load and the prevailing climate data and the particulate matter pollution in particle size PM2.5 or PM10 are shown to you.
The CO2pollution is an important indicator of required ventilation measures and the fine dust particle sizes determined also include pollen, a helpful feature to monitor the air quality for allergy sufferers! In rooms with a large number of persons, CO2 Traffic lights can serve as a means for rough-orientation to indicate whether the air quality is good or poor, as carbon dioxide (CO2) is a reliable indicator of an air change.
In addition to the BQ30 Trotec's range of products includes further professional particle counters such as the PC200 or the PC220. Our particle counters cannot only be used for inspecting the air quality, but to test filter systems as well, for example.
Note: Neither the degree of air pollution caused by particulate matter of the particle size PM2.5 nor the CO2 pollution in the room tells you anything about the infection risk! None of the two values are a measurand of the risk of infection, since there is no correlation between CO2 or PM2.5 concentration and viral load. Learn more about this subject area and several others with regard to virus filtration, filter classes, filter standards and other important operating figures – summarized in our air cleaner-FAQ for virus filtration ...