Coronavirus and UV (ultraviolet light) - What's Safe and What's Not



You may have seen this from the World Health Organisation:

"Can an ultraviolet disinfection lamp kill the new coronavirus? UV lamps should not be used to sterilize hands or other areas of skin as UV radiation can cause skin irritation."


This may cause a little confusion, as UV is effective in killing viruses, however it needs to be used in the right way. They had to state this as it is dangerous to open up skin to UV lamps as they will irritate and burn the skin. Just like being out in the sun for too long without protection.

Nothing beats washing and drying the hands for removing germs from skin, but if you’re looking at disinfecting the air and surfaces then air sterilisers (containing UV) are brilliant at doing this (more on this below).

The WHO’s message on not using UV directly on the skin has been backed up by an article by the BBC.

In summary the article states:

  • UVA and UVB come from the sun and it’s well known how damaging these are to the skin.
  • There’s a third type of ultraviolet light called UVC - a shorter, more energetic wavelength of light. It’s particularly good at destroying genetic material – whether in humans or viral particles.
  • UVC doesn’t get to us as it is cleared by ozone in the atmosphere, but scientists have proven that if you artificially create it, it can be used, and is, as a serialisation method in places like hospitals.
  • Studies to date haven’t looked at UVC and Covid-19 (the particular strain of coronaviruses) but other studies have shown it can be used against other coronaviruses, such as Sars. In fact, UVC is being used in China, to clean down whole buses and UVC-emitting robots have been cleaning floors in hospitals. All whilst there is nobody in the area as it is pure and high level.

So, if it can disinfect, sterilise and kill viruses, how can it be used safely to clean the air and surfaces? How could places that are staying open like small shops, supermarkets, doctors’ surgeries etc really benefit from this kind of virus killing power and transmit a message that the location is doing what it can to sanitise areas without using harmful chemicals?

Air sterilisers that use UV as part of an overall disinfectant strategy.

As stated, to use UV as a standalone method directly on the skin would be highly dangerous, just like being out in the sun without protection.  But it can be used safely when combined with other matter, to clean the air of any unwanted nasties before they have a chance to settle on surfaces, ready to be picked up by hands.

Some technologies have united UV and other items such as ozone, photoplasma, and negatively-charged ions which all exist naturally in the environment to destroy odours, bacteria, viruses, mould, and mildew, and to break down unwanted chemicals and compounds.  The disinfecting happens inside the unit and in the washroom using the by-products created.

UV light and plasma are powerful enough to penetrate the cell walls of microorganisms and shatter the DNA, making it impossible for them to grow and reproduce.

These are perfectly safe to use when channelled in the right equipment, then installed and used correctly.

World Health Organisation:

"Coronaviruses are a family of viruses that range from the common cold to MERS coronavirus, which is Middle East Respiratory Syndrome coronavirus and SARs, Severe acute respiratory syndrome coronavirus."

European Centre for Disease Prevention and Control:

"Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is the name given to the 2019 novel coronavirus. COVID-19 is the name given to the disease associated with the virus. SARS-CoV-2 is a new strain of coronavirus

Although not specifically tested on this new strain of COVID-19, but on the Coronavirus family of viruses, Biozone state that the AirCare solution can destroy the Human Flu virus, H5N1, and Coronavirus in 0.44 seconds (5.7 Log Reduction – Source: CNRS France). (Scientific Report)

The AirCare system improves hygiene both in the air and on surfaces, works 24 hours a day and uses sterilising techniques to clean the environment.

The systems are designed to work in conjunction with general good hygiene practices for optimum results and to act as an ongoing preventative measure.

Many of the solutions are amplifications and magnifications of the naturally occurring phenomena of ultraviolet light, photoplasma, ozone, and photocatalytic oxidation.

We have a new Dryflow® Air Steriliser on its way at the end of April 2020 which uses a UV bulb to create low levels of ozone (in line with the European biocide directive) which acts as a germicidal disinfectant. This has been tested to have a kill rate of up to 98.11% of odour causing bacteria and viruses in air and on surfaces including Clostridium Difficile, Listeria, Staphylococcus aureus, Staphylococcus epidermis, MRSA, and E coli.

Two things happen during this air and surface sterilising process

Inside and outside of the unit as air passes through:

1. Germicidal Irradiation by dual UV light (Ultraviolet) kills microorganisms (bacteria, viruses and mould) by disrupting their DNA and removing their reproductive capabilities.

2. PCO (Photocatalytic Oxidation) - UV reacts with the Catalyst (Ti02) to form highly reactive but short-lived oxidising Hydroxyl Radicals (OH) which act as a disinfectant/steriliser. Hydroxyl radicals have antibacterial, antiviral, sterilising and deodorising properties against pathogenic and non-pathogenic microorganisms. Hydroxyl radicals will eliminate bacteria, mould and fungi, viruses, dust mites, allergens and harmful volatile organic compounds giving you clean healthy air. This interaction creates and breaks down Oxygen molecules transforming them into a highly reactive states of Ozone and Superoxide Ions which leave the unit as “Plasma Quatro”.

Outside the unit, Superoxide Ions clump small particles together to form clusters and remove them from the air as they become too heavy. Standard cleaning regimes can now remove these. Targeted Ozone produced via the specialist lamp gets the hardest to reach areas breaking down contamination in the air and on exposed surfaces. Ozone damages the cell wall of microorganisms stopping reproduction and destroying the cell.

Again, we cannot categorically state that the new Dryflow® Air Steriliser can eliminate this specific strain of coronavirus COVID-19, as sufficient detail about the virus is not yet available. However, outside of the human body, this type of virus (virus with lipid envelopes) falls into the same group as influenza and is one of the easiest varieties to kill.

The Dryflow® Air Steriliser's technology has been tested against a wide variety of micro-organisms that are harder to kill.  These include Clostridium Difficile, Listeria, Staphylococcus aureus, Staphylococcus epidermis, MRSA (gram-positive bacteria), E coli (gram negative bacteria), Aspergillus Fumigatus (fungi) and MS-2 Coliphage (virus without envelope, surrogate for Norovirus due to structural similarities). All have been either reduced or eliminated. It is therefore likely that we would see the same result with Coronavirus.

To view our range of air sterilisers please click here

Summary

As rightly stated by WHO, UV lamps should not be used directly onto the skin as this would be dangerous. However, the sanitising properties of UV, along with other naturally occurring phenomena, can be used to great effect, if safely confined to specialised equipment.

This can be used to sanitise the air of washrooms, hospitals, hotel rooms, super markets, shops etc and has been proven to rid the air of some pretty nasty things, including the coronavirus family, so that it doesn’t have chance to land on surfaces where it can be spread by hand.

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