It has been clear for nearly two years — well before the delta and omicron surges — that wearing N95-caliber masks indoors provides superior protection against the coronavirus than surgical and cloth masks, both for the person wearing them and for others. That is why the White House requires N95s to be worn when around the president and his family — even though staff are also vaccinated and regularly tested.
But the administration has been reluctant to endorse or facilitate the distribution of such masks to the general public as we proposed when President Biden took office last year. In 2020, federal authorities trying to explain why they weren’t urging Americans to wear these masks cited their constrained supply and a need to prioritize the supply for health-care workers. Supplies are no longer limited, though, and they haven’t been for months. Last year and again in the past few weeks, when asked on PBS about whether N95 masks should be worn regularly instead of typical surgical masks, Rochelle Walensky, the director of the Centers for Disease Control and Prevention, instead recommended well-fitting, two-layer cotton masks.
These only filter out, at best, 40 to 60 percent of particles, unlike N95 masks, which block more than 95 percent. She suggested that, despite their efficiency, N95 masks are too uncomfortable for general use, and that if she suggested or required them to be used, people won’t wear masks all the time. Biden’s chief medical adviser, Anthony S. Fauci, has expressed similar views. The reality, though, is that in most places, people already don’t wear masks all the time. Many mask mandates were lifted and never reinstated; in other places, while mandates were reinstated for indoor use, officials still defer responsibility to the public to figure out what to wear. Many people who are still wearing masks, regardless of mandates, are stuck with those of poor quality.
Walensky’s comments may reflect her beliefs from when she was a practicing infectious-disease doctor, as expressed in her editorial in the Journal of the American Medical Association from August 2020: “N95 masks are suffocating, uncomfortable, and difficult to tolerate for long durations.” It is possible that her views are based on older, hard-shell-cup N95 models, such as the 3M 1860, which are often used in health-care settings. For years before the pandemic, the need for N95s was rare, and workers wore them only for minutes at a time rather than entire hours-long shifts — which may be why the question of comfort was never addressed in the past.
We’ve been researching masks since the pandemic began, though, and we’ve found that there are many N95 designs approved by the National Institute for Occupational Safety and Health (NIOSH) that can be worn comfortably for extended periods of time. Many are even more breathable than many two-layer cloth masks, and they’re readily available online and in some stores. Some of these models feature a soft shell or duckbill design that have more surface area for airflow and can mold to a wide array of face shapes to form the seal that prevents infectious particles from escaping around the edges. One example is the Kimberly Clark “pouch” N95 that Walensky herself recently appears to have worn when meeting with the president.
Breathability is largely determined by the “pressure drop” or the resistance the air meets as it passes through the filter material of the mask. A lower pressure drop translates into better breathability. While there is a maximum pressure drop that all N95 masks must meet to be NIOSH-certified, certain designs, especially those with larger surface areas, have smaller pressure drops — and, hence, they’re more breathable — than others. These more comfortable N95s have much smaller pressure drops than cloth and surgical masks, in part because they are not as closely pressed against the nose. In independent testing, a wide range in breathability can be seen among several currently available N95s, with some models twice as breathable as others. For example, the 3M 9205+ has a pressure drop of 119 Pa, whereas the Kimberly Clark Pouch measures 71 Pa, and a similarly shaped model from Gerson only 55 Pa.
Ultimately, most people will only need to wear high-filtration masks for short periods of time and certain situations. Wearing masks outdoors, for instance, is unnecessary unless you’re in a crowd. But wearing just a cloth mask or unfitted surgical mask in a tightly packed train with poor ventilation is likely to be insufficient and can put people at high risk of breathing in infectious aerosols. At certain times, masks are more needed than others, especially when community transmission is high, such as during the surge we are in right now. This is true even for people who are fully vaccinated, largely because our vaccines do not stop infection nearly as well as they stop severe disease and hospitalizations.
Improving the masks that the general public are using can be a critical way to reduce viral spread. The masks function as two-way stops — they stop infectious people from spreading the virus, and they stop healthy people from getting infected. Unlike vaccines, they protect the same no matter what variant we face. And they can be made available at scale immediately, even amid the current surge of the coronavirus’s omicron variant. For example, Milwaukee is giving out free N95s to its residents, specifically one bag of 20 masks per household; New York City is giving out 1 million N95 masks through community-based organizations and clinics; Salt Lake City has mandated respirators for one month and is giving N95 and KN95 masks out free; and Connecticut is mobilizing 6 million N95 respirators. These can also be reused without large drops in filtration efficacy. A bag like this could help a family get through the whole surge.
But we’d all be better off if the federal government, including the CDC, would come out and clearly promote these masks — as well as facilitating their free access either through vouchers or mass direct distribution as officials plan to do for rapid tests. While sufficient supply was a barrier earlier in the pandemic, that is no longer the case. Lack of breathability was then offered as an excuse not to better protect Americans, but that argument may have been based on generalizations about all N95s from a limited number of designs.
The American public deserves better. As we face this unprecedented surge, there are numerous reasons to promote and provide N95-caliber masks — and no reason not to anymore.