What Masks Off on Public Transit Means for the Pandemic

Why is this mandate different from all other mandates?

Updated at 6:50 p.m. ET on April 20, 2022

If you commuted to work today on a bus, train, or metro system, you probably saw more mouths and noses than usual. On Monday, a Trump-appointed federal judge struck down a CDC rule that mandated masks on all U.S. transportation networks, including in airports and on planes. Airline passengers who were mid-flight when the news broke cheered and ripped their masks off, discarding them in trash bags that unmasked flight attendants helpfully brought up and down the aisle.

Over the past several months, vaccine requirements in restaurants, mask mandates in schools and retail spaces, and testing requirements for workers have all been reversed. But the end of airplane masking in particular has inspired a disproportionate reaction—of both extreme relief and utter outrage. One pilot reportedly called the end of the mandate “the most important announcement I’ve ever made.” An ER doctor wondered how “people who claim to love kids are totally cool” with babies dying from COVID. Why, exactly, is this rollback so different from all other rollbacks?

In some ways, the masking rules on transportation should matter less for public health than other masking mandates, not more. Most people who don’t work in transportation probably spend relatively little time in train stations, buses, and Jetways, as compared with workplaces, where mask requirements are already scarce. Joseph Allen, who directs Harvard’s Healthy Buildings program, told me that, in general, ventilation is also better on trains and airplanes than it is in restaurants, offices, and homes. (That’s true only as long as the HVAC system is actually turned on, which it tends not to be while a plane is on the tarmac.) On buses, ventilation depends on whether the driver has the vehicle in air-recirculation mode. “There’s been too much attention on the risk in airplanes for a long time,” Allen said. “Airplanes are not where super-spreading is happening.”

In the broadest sense, removing the transportation-network mandate is not likely to have an enormous, near-term effect on the trajectory of the pandemic. Even if mask compliance on subways and buses suddenly went down to, say, 10 percent in a major American city, any increase in cases or hospitalizations “would probably be small—small to the level of not being detectable by our current surveillance systems,” David Dowdy, an epidemiologist at Johns Hopkins University, told me.

Whether or not masking on buses keeps community spread in check, it has other benefits. “For me, the mask mandate is not simply a tool to control transmission, but rather one that makes our essential spaces safer and accessible for everyone,” Anne Sosin, a public-health researcher at Dartmouth, told me. People who are at risk because they are very elderly, or who get a bit less benefit from the vaccines because they’re immunocompromised, or who have small children, can generally avoid bars and concert venues if they want to. Buses and metros are much harder to steer clear of. Black and Hispanic Americans, who have gotten sick and died at higher rates than their white peers throughout the pandemic, are more likely to use public transportation—and more likely to support mask mandates there.

All the experts I spoke with said the change in policy itself was less significant than the manner in which that change was carried out. Other pandemic restrictions have generally been allowed to expire or repealed by the same authorities that instituted them. The public-transportation mask mandate was implemented by the CDC and repealed by a federal judge in Tampa, Florida. The Department of Justice appealed the ruling today, but if it loses—especially if the case makes it to the Supreme Court—then the federal government’s ability to enact restrictions could be limited far beyond this summer. “If something unpredictable happens next, where we need CDC to put in mandates, that authority’s in question,” Allen said. That could be especially dangerous if the country is dealing with a new variant or a new pathogen that spreads to new areas via interstate travel.

The rollback of the transportation-network mandate also feels different because it was among the very last, broad restrictions that were still in place. Throughout the pandemic, public-health experts have touted a Swiss-cheese approach to protection: No single approach is perfect, whether it be masking, vaccination, or social distancing; but layering them all together helps cover up the holes. Each restriction that gets pulled back is another slice of cheese gone, another way the population becomes more vulnerable. Now, with no more masking on airplanes, trains, and buses, we’re almost dairy-free.

Until this week, transportation hubs were the only place left where many Americans were required to be masked. A handful of regional transit agencies, including in New York City and Portland, Oregon, are still demanding that their riders cover up. But in communities across the country, Americans face few, if any, pandemic restrictions. A vaccination requirement for federal workers still stands. But other than that, Sosin said, “this is the last domino to fall.”