Blast from the Past: UV Air Disinfection

“Are you telling me you built a time machine… Out of a DeLorean?!

-Marty McFly, Back to the Future (1985).

Here at Shelbourne Dental Clinic we deploy a lot of technology. From computerised records systems, to direct sensor digital x-rays, it’s usually a case of looking forward, to the future. But in today’s “Age of Covid” we’re reaching backwards for our latest “technology”, back to the late 1930s in fact! We’ve deployed an ultraviolet system to continually  disinfect the air in our clinic.

So how are we providing modern dental care assisted by technology from over 80 years ago?

Our always-on, 1930s germ-killing death ray! (Don’t try this at home…)

With CoVID-19 we’re facing a highly infectious virus that has an airborne element to it’s transmission. Society was facing a similar (if less dramatic) issue in the 1930s/40s too. Tuberculosis infections, which are also airborne, were widespread during this era.

It was during this era that Ultraviolet-C (UVC) lights were developed and deployed in the USA to reduce the spread of Tuberculosis. The high energy wavelengths of UVC light are known to be highly effective at killing most viruses and bacteria, however they’re also harmful to humans!

Our UVC surface disinfection in action. You don’t want to be in there with this turned on!

The clever bit was to design and place light fixtures in such a way that the UVC light was only in the upper part of a room. That way you can safely occupy the room while the UV light disinfected the air above you.

Diagram showing how upper air UVC lights work

How upper air/room UVC lights work. (from WHO)

As you move around, the air in the room is moved also, so over time all the air in the room will be disinfected. If you have fans of some sort in your ceiling (like ceiling mounted air conditioning) then the rate of disinfection increases hugely.

So if it’s so effective, what happened? Why didn’t it catch on more? Well, antibiotics came along in the early 1940s. These were seen as a magic bullet and the popularity of UV systems faded. They have strong advocates however, including in the Harvard School of Public Health among others. Several US teaching hospitals have operated these systems for decades. They are still widely used in the USA in areas perceived as at risk from tuberculosis.

Modern louvered upper-air UVC in our clinic.

With CoVID-19, interest in such systems is increasing. Major manufacturers are entering the market, and it’s likely you’ll see more of these systems appear in our public and healthcare spaces. They aren’t a silver bullet, but they’re something that further mitigates infection risk. We’re happy to have them installed in all our treatment rooms to help protect you, our patients.

Stay safe!

We’ll leave this equipment in the 1930s where it belongs.

Karl Cassidy - Dublin DentistWritten by .
Doing everything we can to keep us all safe during Covid-19. You can book an appointment online or call our reception team at 01-6655900. And as always, you can email us at – during office hours we always aim to respond to queries within 30 minutes.

Opening Hours

Monday 08.00am - 5:00pm
Tuesday 08.00am - 5:00pm
Wednesday 08.00am - 5:00pm
Thursday 08.00am - 5:00pm
Friday 08.00am - 5:00pm
Saturday Closed
Sunday Closed

Contact Us

7 Grand Canal Wharf, South Dock Rd, Dublin 4
Eircode: D04 R860
Phone: 01 6655900
Fax: 01 6655901

Connect With Us!