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HEPA filtration in the operatory

Keeping patients protected and helping them to feel safe in the dental operatory has always been important, but now, in light of COVID-19, ensuring that your office is the safest in town could make a real difference in how your practice grows over the next year or two.

If you do not currently have a HEPA filtration unit installed in your operatory, here is a quick overview of how the system works and what you should look for when purchasing a HEPA filter for your practice.

The science behind a HEPA (High-Efficiency Particulate Air) filter is fairly simple and not all that dissimilar to how a facemask works. The unit forces air through a fine mesh that traps small particles such as pollen, smoke and in the case of the dental operatory, aerosols that may have bacteria or viruses attached.

Filter ratings

There are two ratings in particular that should be considered when reviewing HEPA filters:

  • What size particles is the filter rated for
  • CADR (Clean Air Delivery Rate)

To qualify as a HEPA filter according to the US Department of Energy, the equipment must remove at least 99.97% of airborne particles 0.3 microns and larger. A machine that meets this minimum qualification is rated as H11. For comparison, an H13 rated system can filter with the same efficiency down to 0.1 microns.

While the COVID-19 virus is measured at 0.125 microns, you may not require an H13 rated filter because the virus only becomes airborne when attached to biological aerosols, which typically range in size from 0.5-3.0 microns, well within the range of an H11 filter.

For Clean Air Delivery Rate, you’re looking at how long it takes the filter to cycle through all of the air within a given room. Calculating the CADR you require is easy, simply multiply all three dimensions of your operatory (h x w x l, in feet) and divide by the number of minutes you’d like the room to be cleaned in.

Cubic Feet / Minutes = CADR

When comparing filter prices and ratings, be sure to take into consideration that while units with higher CADR are more expensive, they will allow for a faster turnaround time to get the next patient into your chair.

Return on investment

HEPA filters are surprisingly affordable and even the higher-end medical grade units will not make a significant impact in your budget, especially when you consider that anything you can do to help make patients feel safer will drive more appointments.