It's Safe to Wear a Medical Mask for a Long Time

During the COVID-19 coronavirus disease pandemic in the spring of 2020, questions have arisen about protective measures. Social media users shared related images, and in one case, a newspaper column claimed that continual or prolonged use of face masks resulted in breathing too much of one’s own exhaled carbon dioxide, which can lead to health concerns.

“Dr. Dennis A Castro B” wrote in the Nigerian newspaper Vanguard, for instance, that prolonged use of face masks causes hypoxia.

The post does not specify what kinds of masks cause these issues (though the article image does show N95 respirator masks), nor does it indicate whether this affects people with respiratory conditions more. 

But research articles and experts suggest that such extreme symptoms are unlikely to occur in most people. Dr. Abrar Ahmad Chughtai, an epidemiologist and lecturer at the School of Public Health and Community Medicine at University of New South Wales Australia, says the risk of hypoxia and hypercapnia are unlikely to take place with cloth and surgical masks, because they are not tight-fitting.

The N95 respirator is an example of personal protective equipment (PPE) usually worn by health workers to protect the wearer from airborne particles and from liquid contaminating the face. The Centers for Disease Control and Prevention (CDC) does not recommend that the general public use these masks because health workers and other medical first responders need them more. 

N95 masks are estimated to reduce oxygen intake by anywhere from 5 to 20 percent. That’s significant, even for a healthy person. It can cause dizziness and lightheadedness. If you wear a mask long enough, it can damage the lungs. For a patient in respiratory distress, it can even be life threatening.

Ultimately, the impact of a mask on its wearer depends on the wearer’s health, any pre-existing respiratory illnesses, the type of mask, and the length of time the person wears it. In most instances, the effects of prolonged cloth mask usage are small. Masks, like most short-term measures to prevent the spread of COVID-19, should be worn only if the wearer has to be in close proximity to others, and be used in addition to necessary measures like social distancing, and more. As such, we rate this claim about the dangers of masks as “Mostly false.”

In summary, breathing in excessive carbon dioxide is dangerous for the body. Some people with preexisting respiratory illnesses may face health issues only with prolonged use of tight-fitting masks, such as respirators. However, people wearing cloth or surgical masks are in little to no danger of breathing in unhealthy amounts of carbon dioxide.