Facts and Fakes

In multiple Facebook-messages, warnings are posted of facemasks detering breathing. Breathing in and out in the mask would lead to you inhaling more CO2, eventually sufficating you.

These posts are false, the masks required by most governments do not fit tightly enough to keep fresh air from reaching your mouth and nose.

What is the source?

The message that mouth masks would lead to an oxygen deficiency or CO2 poisoning seems to spread all over the world. Argentine, American, Italian and British fact-checkers, among others, have already looked at this claim.

We have not been able to find out where these messages come from, but they seem to have started circulating mainly after the American equivalent of the RIVM, the CDC, advised Americans in April to wear face masks in public spaces.

Why is there no risk?

All foreign fact checks showed that the face masks that are mandatory in the Netherlands in public transport do not cause oxygen deficiency or CO2 poisoning. The World Health Organization (WHO) has also stated that wearing a mask can be uncomfortable, but does not lead to oxygen deficiency or CO2 poisoning.

This is because these masks are air permeable. A disposable paper mask or, for example, a reusable textile mask allows oxygen and CO2 molecules to pass through. In addition, face masks rarely fit perfectly around the face, this means air can also flow in and out from the side. If you make a face mask yourself, it is important that you use material that you can easily breathe through and that you do not use, for example, a plastic sandwich bag.

In 2012, the CDC examined the effect of wearing a face mask on 20 healthy people who walked for an hour. The researchers discovered that face masks regularly create an annoying warm air around the face, but that face masks had no appreciable effect on, among other things, heart rate and CO2 levels.

Hans in 't Veen, lung specialist at Franciscus Gasthuis & Vlietland, previously explained to AFP news agency that a face mask can indeed feel unpleasant. "As a result, it is possible that people start to breathe incorrectly, causing them to hyperventilate. This does not cause an oxygen deficiency or excess CO2 and is not dangerous in itself."

What if a face mask is oppressive?

The Longfonds has placed a number of tips on its website to reduce shortness of breath through face masks. For example, it recommends using a thin, but dense fabric if you make a mask yourself and to practice wearing a face mask at home. The Longfonds also advises to be at the bus stop or platform on time, so that you are not already short of breath from cycling or walking when you put on your face mask.