A doctor in Dublin, Ireland, has gotten so many misinformed patients asking him if a face mask lowers a wearer’s oxygen levels that he decided to make his answer easy to understand and to make it public.

On July 14, Dr. Maitiu O Tuathail, whose Twitter profile states he is a general practitioner, posted a 70-second video standing next to a machine that measures oxygen saturation levels in the blood. With a monitor clip over his index finger, Tuathail is seen putting on a disposable medical mask. Then another one. And another. At the end of the clip, the doctor is standing with 6 masks on his face, while the numbers in the display remain steady and near-perfect — the oxygen saturation level fluctuates slightly between 98 and 99 percent.

Let’s hope this brings the whole debate surrounding face masks and their efficiency to an end. Or at least closer to it.

Dr. Maitiu O Tuathail said he’s met a lot of people who were misinformed about face masks

Image credits: DrZeroCraic

Image credits: DrZeroCraic

Image credits: DrZeroCraic

Image credits: DrZeroCraic

Image credits: DrZeroCraic

So he decided to debunk one of the most popular myths surrounding them

Image credits: DrZeroCraic

And posted this video

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Face masks are recommended, if not required, in public settings throughout many places around the world to protect wearers from contracting or spreading the novel coronavirus. Because they work.

A recent analysis of coronavirus outbreaks in 42 countries found that countries where mask wearing was common, like China and Japan, saw more modest outbreaks compared with nations that weren’t accustomed to the practice. “We believe broader mask use is key to control the pandemic,” the researchers wrote.

Bill Nye the Science Guy also turned to social media to demonstrate why face masks are important

Image credits: Bill Nye

@billnye##WearAMask ##LearnOnTikTok ##TikTokPartner

♬ original sound – billnye

They even added this rhetorical question: “Is it not better to adopt a possibly imperfect protective measure, rather than waiting for more evidence at the expense of human lives?”

A model from the University of Washington predicted that the US could prevent as many as 33,000 coronavirus deaths by October if 95% of the population wore face masks in public.

Dr. Tuathail’s clip even started an interesting discussion

Image credits: DRaburski

Image credits: fhayesmccoy