Publisher Health

A federal judge in Florida struck down the federal mask requirement for planes and public transit on Monday, which had been set to expire on May 3. Within 24 hours, all major U.S. airlines, as well as the Amtrak rail system, had declared that they were no longer requiring masks for passengers or employees.

The White House said on Tuesday evening that it would appeal the ruling if the Centers for Disease Control and Prevention decided that there is a public health basis for trying to reinstate the mandate. The C.D.C. said in a statement on Wednesday evening that it had asked the Justice Department to proceed with an appeal.

What does all this mean for travelers? Here’s the latest on the evolving situation — which could soon change again.

Do I need to wear a mask on a domestic flight?

No. Wearing a mask on a plane is currently optional on all major U.S. carriers for both passengers and crew.

What about in airports?

While most U.S. airports no longer require masks for travelers or staff, some exceptions include New York’s John F. Kennedy International and La Guardia airports and Philadelphia International Airport. Each airport makes its own rules, so it’s possible these requirements could change.

What if I’m flying internationally?

Face coverings may still be required to or from some international destinations, depending on either that country’s or the airline’s rules.

Mask rules onboard vary from country to country. Many nations, including China, Canada, France and Germany, for example, still require all travelers to wear masks on planes departing from or arriving into the country. But in Mexico and in many parts of the Caribbean it is up to the airline to set its own rules.

Several international airlines, including British Airways and Virgin Atlantic, updated their policies on Tuesday to make masks optional on flights to U.S. destinations. They had previously stopped requiring masks on many routes to the Caribbean.

Do I still have to test when flying into the United States?

Yes, indeed. Every traveler over the age of 2 flying into the United States, regardless of vaccination status or citizenship, must show a negative coronavirus test taken the day before boarding. Alternatively, people who have tested positive in the past 90 days may travel with positive viral test results and a signed letter from a licensed health care provider or a public health official saying that they have been cleared for travel.

Unlike the federal mask mandate, there is no expiration date on this requirement. Airlines and trade organizations representing the hospitality industry have been lobbying for the C.D.C. to lift the requirement, which they say is financially damaging. The White House said earlier this month that there were no immediate plans to remove the rule.

Can I get refunded if I’m not comfortable flying amid unmasked people?

It depends. Airlines do not seem to be offering any special type of refund for people in this situation. If you booked a nonrefundable fare, you may be out of luck. Your best bet may be getting a credit or rebooking the flight for some distant date; most airlines no longer charge change fees on all but basic economy flights.

If you are flying Delta, though, you can plead your case. “We hear situations out on a case-by-case basis and make a determination,” a spokesman for Delta said on Wednesday.

Southwest offers a voucher or a refund, depending on the type of ticket.

In response to this question, American Airlines sent its standard refund policy which requires a traveler to cancel within 24 hours on a nonrefundable ticket.

The sudden change of mask rules has caused anxiety for some travelers. Susanna Speier, 49, who has Crohn’s disease, is among the many immunocompromised Americans now grappling with what to do about upcoming travel plans. When she committed to attending a conference in Austin, Texas, on April 28, Ms. Speier, who lives in Denver, understood that everyone on the plane would be wearing a mask.

“I’m angry that the airlines are doing it and that they are doing this suddenly,” said Ms. Speier, who writes a newsletter about living with a weakened immune system.

Are masks required on cruise ships?

Mask-wearing is optional on most major cruise lines, including Carnival Cruise Line, Royal Caribbean and Norwegian. Most cruise companies sailing on U.S. waters have opted in to the C.D.C.’s voluntary sailing order, which does not require cruise passengers to wear masks onboard ships when 95 percent of crew and passengers over the age of 5 are fully vaccinated.

Following Monday’s ruling on mask mandates for public transportation hubs, masks are no longer required to be worn in cruise terminals. Mask rules for international ports vary by destination and should be checked before disembarking.

How about other mass transit?

It depends. Since the federal transportation mandate no longer holds, public transit systems may set their own rules in accordance with city, county or state health authorities. As of Wednesday, riders are still required to wear masks while taking public transportation in New York City and Portland, Ore., but not in Washington D.C. or Los Angeles for example. The Amtrak rail system said passengers and employees would no longer need to wear masks on trains or in stations. Adding to confusion, though, mask-wearing may be required in some train stations that choose to enforce it.

What about taxis and ride-hailing services?

Masks are no longer mandated in taxis, and both Uber and Lyft has stopped requiring riders and drivers in the United States to wear face coverings. But local regulations can supersede these policies. In New York City, for example, masks are still required in Ubers, Lyfts and taxis.

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