Coronavirus Information Center

VANCOUVER, BRITISH COLUMBIA - APRIL 4: Reporter Wendy Luo holds up a N95 mask manufactured by 3M, one of the only masks that guards against germs such as severe acute respiratory syndrome (SARS) April 4, 2003 in Vancouver, British Columbia, Canada. A SARS clinic opened at noon today at St. Vincent's Hospital in Vancouver, British Columbia, Canada. SARS is a flu-like illness which has killed at least 80 people, mostly in Asia, and more than 2,200 have been infected around the world. U.S. President George W. Bush listed the mystery virus as a communicable disease by executive order today. (Photo by Don MacKinnon/Getty Images)

With the CDC’s (Center for Disease Control’s) recommendation to cover one’s face to prevent the spread of coronavirus, and state official’s guidelines on returning to work, many Americans are searching for ways to cover their nose and mouth throughout their eight to twelve-hour shift.  Some are able to access the top of the line masks such as the N95 respirators while some have made and used decorative cloth face coverings.

However, mask fatigue and reports of “difficulty breathing” while wearing a facial covering begs the question, “are some of us losing oxygen or building up carbon dioxide while wearing a mask?”

Mask Fatigue: Do Workers Need “Mask Breaks?”

Last month a car accident in New Jersey was reported when a driver, wearing an N95 mask, became syncopal and passed out, “crashing” the vehicle.  The report was later revised as authorities believed it could have been a “contributing factor” to the accident. The driver was treated for non-life-threatening injuries.

A mask that covers the nose and mouth provides a barrier from the outside environment.  The effectiveness of the barrier varies depending on the materials used.

N95 respirators appear to be the most protective.  They are designed to keep pathogens out during oxygen and carbon dioxide exchange.  They are made from non-woven polypropylene fibers and they are >95% efficient at filtering 0.3-μm particles (smaller than the average 5μm particles given off during coughing and talking).  Breathing is easily managed while wearing a properly fitted N95 mask.

In breathing, we inhale air, extracting the oxygen in our lungs, while exhaling carbon dioxide, a byproduct from the body’s metabolism.

However, some people may require less of a barrier in order to get the oxygen requirement they need.  These individuals include those who may suffer from heart conditions or respiratory illnesses, such as emphysema and COPD. They may breathe too shallowly, not releasing the carbon dioxide that has accumulated.

If one has difficulty releasing the carbon dioxide they build up, they can become hyercapneic.  Hypercapnea is a condition where one may present with headaches, dizziness, fatigue, shortness of breath, difficulty focusing, and if severe can cause muscle twitching, confusion, abnormal heartbeats, seizures, and fainting.

In 2006, a study of 212 healthcare workers found 37.3% to suffer from N95 mask related headaches, most of whom reported an average of 6 a month. Authors concluded that continuous use of mask-wearing (approximately 4 hours) could induce headaches and shorter durations of use may mitigate the frequency and severity of the risk.

Infectious disease expert Amesh A. Adalja, MD, senior scholar at the Johns Hopkins Center for Health Security in Maryland, told Health, “Someone wearing an N95 mask for a prolonged period of time may have alterations in their blood chemistry that could lead to changes in the level of consciousness if severe.”

Studies could be designed to give more conclusive data on blood oxygen and carbon dioxide level changes as one wears a mask for certain periods of time, but for now, we don’t have definitive guidance on how long a mask should be worn to prevent hyercapneic symptoms. We are, however, urged to wear masks to prevent our spread of germs.

Therefore, for those who may be susceptible to breathing issues and are working long shifts that require facial coverings to be worn, I suggest speaking with one’s medical provider as management may be needed for their respiratory and/or cardiac condition.  Mask breaks can also be an option. Mask breaks can occur outside or in “safe rooms” that are not open to the public to allow one to get some uninhibited air before replacing the mask and returning to one’s work.

Daliah Wachs, MD, FAAFP is a nationally syndicated radio personality on GCN Network, KDWN, and iHeart Radio.