Can an antiviral air filter help reduce virus transmission?
Advice for reducing transmission of COVID-19 has varied throughout the pandemic as the scientific community did all it could to better understand the complexities of the virus. Good ventilation is now seen universally as an effective way to lower transmission risks, with consistent air circulation helping disperse lingering airborne particles.
The UK Government has said that, “bringing fresh air into a room and removing older stale air that contains virus particles reduces the chance of spreading COVID-19. The more fresh air that is brought inside, the quicker any airborne virus will be removed from the room”.
The World Health Organisation has long reported increased risk for indoor transmission vs outdoor, with recommendations being to ensure air is constantly being circulated to lower that risk (alongside other precautionary measures).
While the more general advice points to ensuring windows and doors are open when gathering inside, increasingly we are looking towards how technology can help combat airborne threats.
HEPA filters are currently seen as a key solution in this battle, with many authorities including the Irish government now considering adding them to schools.
Recent studies have even shown that using antiviral air filter technologies like HEPA filters can help remove coronavirus particles from real-life COVID wards.
While it’s encouraging to see increased discussion of air filtration technology as a way of combating airborne virus transmission, it’s important to fully understand the technology and its limitations before bringing in widespread reform.
What is a HEPA Filter?
A HEPA (High Efficiency Particulate Air) filter is a mechanical filter that filters small air particles at a higher rate than traditional air filters.
HEPA filters can trap harmful particles from the air, removing them from circulation within an indoor environment. For this reason, they are seen as particularly useful for combating airborne viruses, for which droplets can linger in the air, leading to transmission.
Applications of this kind of device are recommended most often in environments where good ventilation isn’t an option, such as in this guidance from HSE:
You can use local air cleaning and filtration units to reduce airborne transmission of aerosols where it is not possible to maintain adequate ventilation.
These units are not a substitute for ventilation. You should prioritise any areas identified as poorly ventilated for improvement in other ways before you think about using an air cleaning device.
Limitations of HEPA Filters
Any improvement on air quality and ventilation should be seen as a positive, but the limitations of these devices should also be considered.
As is noted in the above guidance, air cleaning devices like HEPA filters shouldn’t be considered a substitute for other hygiene or safety practises.
As is the case with some types of PPE, the deployment of technology such as HEPA filters can lead to a false sense of security if users consider themselves over-protected. While there is likely to be a reduction in harmful airborne particles, it doesn’t guarantee to stop transmission.
In 2020, the UK Government released the results of a study on the Potential application of Air Cleaning devices and personal decontamination to manage transmission of COVID-19. Amongst the results they found that the use of HEPA filters saw a maximum reduction of just 62.1% of COVID-19 particles from the atmosphere.
Traps But Doesn’t Kill
Even the top performing HEPA filters only trap harmful pathogens and will do nothing to remove or destroy them. Over time, large amounts of the trapped particles begin to accumulate in the filters before they eventually become clogged.
The build up of the filtered particles can be extremely damaging to the efficacy and efficiency of the filters. Firstly, there is a drop in performance due to the clogged filters no longer being able to circulate air as efficiently.
Secondly, the filters require more frequent cleaning, maintenance and replacement - which combined can prove extremely costly.
Lastly, as the filters become clogged with harmful pathogens, they also become potential breeding grounds for bacteria and virus growth.
The Ideal Antiviral Air Filter
The ideal solution for indoor air filtration is a system that both traps and removes harmful bacteria and pollutants including coronavirus - just like the Vent-Axia PureAir Room 500 X, which is powered by the CodiKoat HEPA PLUS filter.
HEPA PLUS traps and kills harmful viruses, bacteria and fungi, including coronavirus, within seconds of filter contact. There is no clogging or build up of harmful particles, enabling it to operate at optimum energy and cost efficiency for longer.
By introducing a filter that will trap and remove harmful bacteria, we can move towards a system that is more efficient, more durable, more sustainable, more cost effective and will help reduce overall virus transmission.
For more information about HEPA PLUS, please get in touch here.