Skjalg Johnsen explains why he is using UVC lighting to help combat the COVID-19 virus and reduce fallow times in surgeries.
The fallow time due to coronavirus is now causing huge problems for dental practices. My wife and I are running a busy four-surgery private practice in Southsea. During the lockdown we quickly realised that we needed to do something about the 60 minutes fallow time.
For everyone in the dental team, this is a challenge when you have to consider the fallow time after each high risk AGP treatment. This is especially true for the reception team, who would usually book wherever there is a gap in the clinicians’ diary.
We started reading articles and researching for a way around this. The common answer we found was air filtration with HEPA filters, combined with/or hydrogen peroxide vapour/hydrogen peroxide dry mist.
This led me to contact a good friend of mine who is also a civil engineer for advice. After some calculations he dismissed the air filtration technique as taking a very long time. More importantly he pointed out we cannot be sure the virus is inactivate. Plus, hydrogen peroxide with its bleaching and damaging effect to surfaces could quickly cause a refurbishment of the surgery.
The answer he suggested was UVC/UVGI (ultra violet germicidal irradiation).
Using UVC in the dental practice
Luckily the coronavirus is rather easy to kill according to anti-viral scientists. With its thin membrane the energy needed to inactivate it is rather small.
Tests at the beginning of June 2020 at the university of Boston confirm that an energy level of just 6mj/cm2 is all that we need to irradiate coronavirus. UVC will target the DNA or RNA and inactivate any bacteria, viruses and fungus. So even for other viruses like the seasonal flu, the UVC is very effective.
The technique is old but never really became popular since it produced ozone, which is classified as a poisonous gas. With more modern technology, the negative effect of producing ozone has now been eliminated. Therefore, hospitals are now using UVC more and more for germicidal cleaning. We clean our water this way and lately the New York underground has started using this method. So, after collecting and processing all this information, UVC really interested us.
Looking at different options we now have a mobile 1,000W UVC device, which has a germicidal power of 1,700 mj/cm2. It will irradiate the coronavirus aerosol in two x two minutes (two different positions in the surgery). Furthermore, we can easily move it between surgeries on the same floor.
Investment-wise this was really a no-brainer. The lifespan is at least 8,000 hours. And since we need only four minutes after high risk AGP, we use it less than one hour per day. This device will probably last until I retire! Even after coronavirus, we will continue using this to keep our staff and patients safe.