Several US airlines and train systems have dropped their mask mandates after a federal judge struck down the Centers for Disease Control and Prevention's face-mask mandate for airplanes and public transit.

The requirement was put in place by the Biden administration in February of 2021.

The airlines dropped their mask mandates.

Alaska Airlines

It has been a long time since the last change. Alaska Airlines vice president of safety and security Max Tidwell said in a statement on Monday that he could not be prouder of the frontline employees who have handled every pivot.

United Airlines

In a statement, United Airlines said that masks were optional.

The company said in a statement that masks are no longer required at United on domestic flights, select international flights, or at US airports.

Southwest Airlines

Southwest Airlines will allow employees and customers to choose whether or not to wear a mask, and we encourage individuals to make the best decision for their personal wellbeing.

American Airlines

American Airlines added that face masks may still be required based on local ordinances, meaning that the four largest airlines in the US have all dropped the requirement.

JetBlue Airlines

The requirement was being moved away from the four airline companies.

In line with Monday's federal court ruling and the Transportation Security Administration's guidance, mask-wearing will now be optional on JetBlue.

Amtrak

transit agencies are trying to figure out whether or not to enforce CDC guidelines The agency told Insider that anyone who needs or chooses to wear a mask is encouraged to do so.

The mandate overturned

The CDC overstepped its powers with the initial guidance, according to a ruling by a Trump-appointed judge on Monday.

She said in the ruling that the system doesn't allow agencies to act illegally even in pursuit of desirable ends. The Transportation Security Administration will no longer enforce the mandate after the Biden Administration announced that it would stop.

Danielle Blevins, spokeswoman for the agency, told Insider that they were reviewing the decision and wouldn't comment further.

The onus is on individual airlines, customers, and transit agencies to decide how to enforce guidelines as companies and agencies wait to see if the government will appeal the ruling.