With summer comes outdoor activities and plenty of fresh air. But really, how fresh is the air we breathe if we’re wearing a mask? When asked this question in a recent Facebook Live event, a specialist in charge of infectious disease at a Midwest-based healthcare system said wearing a mask outside is fine and there’s no reason to be concerned about breathing too much of your own carbon dioxide.

While this is one of several myths circulating on social media networks, Dr. Robert Citronberg said there is no scientific evidence showing that wearing a mask can be harmful, even for long periods of time. He went on to confirm that wearing a mask is still one of the best ways to stop the spread of COVID-19.