How Much Does One-Way Masking Protect You From COVID On A Plane?

After a federal judge in Florida struck down the mask mandate on planes and other forms of public transportation on Monday, most major airlines — including American, Delta, United, Southwest, Alaska, Spirit and JetBlue — swiftly announced that masks were no longer required on domestic flights and certain international flights.

While some passengers are thrilled that they no longer need to wear masks, many others are concerned about the safety of using mass transportation among a bunch of maskless strangers. But infectious diseases specialists say one-way masking is still worth it.

“We like to think of situations as being safe or unsafe, but the question of masking effectiveness falls onto a gradient,” said Dr. Andrew Handel, a pediatric infectious diseases expert at Stony Brook Children’s Hospital. “One-way masking is less effective than two-way masking, but is more effective than not wearing a mask at all.”

One-way masking is very protective ― especially when a high-quality mask like an N95, KN95 or KF94 is worn, since they can better filter viral particles out of the air you breathe. Though cloth masks and surgical masks do little to protect us against the coronavirus’ extremely contagious omicron variant, studies have shown that a good, well-fitting mask significantly decreases how much virus a person is exposed to, which in turn lowers the chances they’ll get infected.

“With omicron, better masks such as surgical or higher are preferred,” said Dr. Amesh Adalja, an infectious diseases expert and senior scholar at the Johns Hopkins University Center for Health Security.

After all, this is what doctors treating COVID patients have been doing in intensive care units across the country. Adalja routinely one-way masks (mostly with an N95, but occasionally with a surgical mask) when treating patients with tuberculosis or COVID in the hospital.

“It is very safe and the norm,” Adalja said, adding that the same applies to the general population.

Airplanes also have great air filtering systems that remove the vast majority of SARS-CoV-2 from the air. This makes flying safer than many other crowded indoor activities where masks haven’t been required, according to Adalja.

Many experts advise people to continue to wearing high-quality masks while in crowded settings like airports, planes or trains ― especially people who are at risk or immunocompromised.

“I would recommend an N95, KN95, FFP2, KFN94 or double masks (surgical plus cloth) on public transportation if patrons want less exposure, per the physical science studies,” said Dr. Monica Gandhi, an infectious diseases specialist with the University of California, San Francisco.

If you choose to one-way mask, you’ll want the mask to fit snug to your face so there aren’t gaps around your nose, cheeks or chin. The more gaps there are, the more opportunities a virus has to sneak in.

While the majority of young kids are not at risk of severe disease from COVID ― especially if they’ve already had COVID or have been vaccinated ― you still want to protect them. Flying around other unmasked passengers may feel unnerving, especially for parents with kids who don’t yet qualify for the shots.

Each parent will have to consider their child’s health when determining whether they should mask while traveling. “For high-risk children who can wear a mask, one-way masking works,” Adalja said.

Experts also recommend turning on the air vent above your seat to keep filtered air flowing around you.

If your child is at risk or unvaccinated, Handel recommends minimizing the amount of time your family spends hanging around the airport unmasked. “Airplanes have better air circulation than we give them credit for, which reduces the risk of contracting COVID,” he said. “But we should keep in mind the other steps [needed] for traveling, like sitting in the airport or in a crowded location, where we can also contract COVID.”

Additionally, making sure that family members are vaccinated will help keep young kids safer from getting infected. Being extra cautious with those young kids, by having them and any co-travelers wear a mask, will make them less likely to get COVID, Handel said.

Experts say that people who have immunity are already well protected from serious illness. Even if your antibody levels wane four to six months after vaccination, in most cases, the immune system will still be able to fight the virus and keep people safe from severe illness, hospitalization and death.

“I think for healthy people who are vaccinated or have prior infection, that they can consider themselves heavily protected against what matters most: severe disease,” Adalja said.

That protection increases when people, including those who have risk factors for severe COVID, also wear a high-quality mask. Anyone who’s been vaccinated and is wearing a high-quality mask in an indoor setting can generally feel safe, Adalja said.

Experts are still learning about COVID-19. The information in this story is what was known or available as of publication, but guidance can change as scientists discover more about the virus. Please check the Centers for Disease Control and Prevention for the most updated recommendations.