The face masks requirement for planes, buses and trains has been prolonged to mid-September

Passengers, almost all with face masks, board an American Airlines flight to Charlotte on May 3, 2020 in New York City.

Eleanor Sens | AFP | Getty Images

Are you traveling this summer? Don’t forget your mask.

The Transportation Security Administration on Friday expanded a federal obligation requiring travelers to wear face masks on buses, trains, commercial flights and at airports. The requirement expired on May 11th and is now valid until September 13th.

In February, by order of the Centers for Disease Control and Prevention, the agency demanded that people wear masks during flights, buses, trains and public transport.

For the most part, airlines have required passengers to wear masks over the past year as Covid-19 continued to spread. The airlines have banned more than 2,000 passengers for non-compliance with mask requirements.

The Federal Aviation Administration introduced a “zero tolerance” policy for recalcitrant travelers in January after a surge in reports, many of them from travelers refusing to wear masks.

“Mask compliance is key to having confidence in air travel on the way to recovery, including international travel,” said Sara Nelson, international president of the Association of Flight Attendants-CWA, the union that represents cabin crews at United, Spirit and others than a dozen airlines.

“We are also responsible for ensuring that aviation does not contribute to the spread of the virus or any other variant. We applaud Administrator Pekoske and the Biden Administration for taking steps to ensure we can better dismantle,” Nelson said.

About half of adults in the United States are at least partially vaccinated, according to federal data. Airline executives have reported higher bookings since vaccines were introduced and more tourist attractions reopened.