The Airborne Offensive – Keeping the Air Clean

It seems as if the hospitality industry is at war with Covid-19. And as any military commander will tell you, we cannot afford to overlook the strategic importance of the air.

The scientists agree. The World Health Organisation (WHO), as the ultimate authority on matters of infection and Covid contamination, warns that, despite all our cleaning and sanitisation of fomites (surfaces that could be contaminated with Covid virus particles) “There are no specific reports which have directly demonstrated fomite transmission.”  

Closer to home, Fiona Henriquez,  Professor in the School of Health and Life Sciences at the University of the West of Scotland, says:

“This virus is airborne. It is contained in very tiny droplets and aerosols that do not necessarily come to earth very rapidly. So, they stay in the air for longer periods of time because they are very light.”

So, the WHO doubts that anyone has ever become infected with Covid by touching a contaminated surface and Professor Henriquez confirms that the virus floats around in the air, exhaled by infected people and inhaled by people in the vicinity.

The UK government has acknowledged this too, with its advice of “Hands. Face. Space.” The virus floats in the air, so we need to keep our distance from each other.

However, the main activity we see in customer-facing businesses UK-wide is surface cleaning: staff continuously cleaning touch points such as handrails, tables, chairs and handles.

This is important for general hygiene as well as to inspire customer confidence. It is crucial as the first layer in a multi-layer approach. We can see this as the equivalent of the ground armies in a military campaign.

 

Airborne Supremacy

The next level is to stop airborne transmission of the Covid virus. Our military general will explain that we need to control the air. How do we do that?

The good news is that we have potent weapons available to clean and improve the air in our venues. These two weapons complement each other perfectly.

Weapon 1: 24/7 Air Sanifier

An air sanifier works quietly and unobtrusively, 24 hours a day, 7 days a week. It draws in air, cleans, treats and improves it and then disperses it back into the room or space. It works in four ways:

  • Germicidal irradiation via dual UV (Ultraviolet) light – kills microorganisms (bacteria, viruses and mould)
  • PCO – Photocatalytic Oxidation, UV light reacts with our Catalyst (Ti02) to form Hydroxyl Radicals (OH) which destroy carbon-based pollutants (airborne pathogens, viruses, bacteria, fungi, mould spores, dust mites and allergens), odours and harmful gases transforming them into harmless substances.
  • The unit generates ozone at a safe level for occupied spaces or rooms (below 0.2 ppm). Ozone is fanned to every inch of the room, breaking down airborne and surface contaminants, including Covid-19.
  • Superoxide ions generated in the same process change the polarity of airborne contaminants so they clump together and fall to the floor. Effective on particles as small as 0.0001 micron – better than the best HEPA filter.


The advantages of the air sanifier, as outlined above, are clear.

There are extra benefits, too:

  • It uses no chemicals and actually destroys allergens, so it is ideal for clients with allergies or compromised respiratory systems
  • The ozone generated naturally leaves the air smelling fresh and clean
  • As it runs continuously, it is reassuring and comforting for clients, who notice it running all the time. And it needs no scheduling, so no increase in workload for the housekeeping team.


The only limitation is that its power is restricted so that it is safe for use in rooms of continuous occupation, even nurseries. This means that it will kill most pathogens but not all, so some Covid microbes may survive treatment.

However, this is not a problem in an integrated, multi-layer strategy, which takes us to our next weapon in the battle for airborne superiority…


Weapon 2: Ozone Purge

The next level up in cleaning the air is portable Ozone Purge equipment.

This is very powerful, as it produces high levels of ozone (1-3 parts per million), guaranteed to kill all pathogens in the air and on surfaces. Like the 24/7 sanifier, it is also highly effective at removing odours, fungi, allergens, dust mites, etc.

The equipment produces ozone and fans it around to cover the entire room, disinfecting the air and sanitising every surface, soft and hard. While a human operative carrying a hand-held spray or fogging device might miss a spot, this equipment reaches everywhere: behind radiators, in cupboards, etc.

Professor Henriquez pointed out the importance of this universal reach at a recent webinar for the hotel industry on sanitisation in times of Covid. She advised housekeepers when cleaning rooms:

“Check the corners. Just because you can’t see it, doesn’t mean it’s not there. How many times I’ve gone into a room, checked a radiator and seen the dust. Those are the places where microbes accumulate and then get ventilated up into the room through the heat of the radiator, for example.”

One limitation of this equipment brings with it an advantage: the high level of ozone produced means that the room must be unoccupied while the equipment is in use. However, this also means that it works unsupervised, while housekeeping staff can deal with other tasks.

Because the equipment operates unseen, it does not have the “theatre” of more visible measures. However, there is always the option of a small notice in rooms or spaces, advising that Ozone Purge equipment is regularly deployed.

The Ozone Purge equipment converts ozone back to ordinary oxygen as part of its operating cycle, making the room or space safe to occupy immediately after treatment.

Like the 24/7 sanifier, the equipment leaves the room smelling naturally fresh, although it uses no chemicals, which is good news for allergy sufferers, babies and young children and anyone with a compromised respiratory system.

Is this equipment safe to use?

Absolutely. Ozone is simply a form of oxygen that already occurs in nature. This equipment simply increases the proportion of ozone to oxygen temporarily. It is chemical free, low residue, not damaging to surfaces and has a low carbon footprint.

The safe level of ozone indoors for continuous occupation is 0.2 parts per million (ppm) of ozone per particle of air. As this equipment generates between 1 and 3 ppm, it is recommended that the room is unoccupied during operation. The worst-case scenario if a person remained in the room for a long time while the equipment was operating is that they might develop a headache or possibly feel nauseous.

It is portable, so can be moved from room to room, switched on and left to work. This means nobody needs to be in the room while it is in operation. The size of the room (width, length & height) and the amount of solid furniture in it will determine the amount of time required for operation. An average hotel room (around 100m3) will require around 45 minutes for a full and effective purge.

What about Fogging machines?

Sometimes touted as an alternative to Ozone Purge equipment, fogging machines emit a mist of disinfectant spray from a handheld device within a closed room or sealed space. Fogging is intended as a surface cleaning measure.

The WHO does not recommend fogging machines for several reasons, which are neatly summarised in this quote from a WHO report:


“In indoor spaces, routine application of disinfectants to environmental surfaces by spraying or fogging (also known as fumigation or misting) is not recommended for COVID-19. One study has shown that spraying as a primary disinfection strategy is ineffective in removing contaminants outside of direct spray zones. Moreover, spraying disinfectants can result in risks to the eyes, respiratory or skin irritation and the resulting health effects. Spraying or fogging of certain chemicals, such as formaldehyde, chlorine-based agents or quaternary ammonium compounds, is not recommended due to adverse health effects on workers in facilities where these methods have been utilized.”


We would add that fogging machines are primarily a surface cleaning measure, very labour intensive and subject to human error, as they are only effective in places where the operator has pointed the nozzle.

Furthermore, the residual chemicals left behind after a fogging session can be problematic, especially for children, and people with respiratory problems, such as asthmatics and smokers.

In our next chapter, we look at harnessing the power of technology in our war against Covid. 

Free Assessment

To book your free venue assessment with the sanitisation experts at Elytraa Group, contact us on 01786 439839 or info@elytraa.com.