Airlines will now allow passengers to fly without masks after Biden's mandate allows for medical exemptions

• American Airlines and Alaska Airlines issued new policies that allow exceptions for mask-wearing.
• Flyers with a medical condition who get a doctor's note and negative COVID-19 test can go maskless.
• President Biden issued an executive order mandating mask-wearing on all public transportation.

The Centers for Disease Control and Prevention's mask mandate for air travel took effect on February 2, requiring flyers to mask up or face the consequences following an executive order from President Joe Biden. But as the policy goes federal, the Americans with Disabilities Act is pumping the brakes on enforcement when it comes to some flyers.

Specifically exempted from the order are those who can't wear a mask due to a medical condition, as part of the few exceptions allowed by the CDC. Other carve-outs include flyers younger than two years of age and those who cannot wear a mask due to workplace safety regulations.

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Airlines had cracked down on medical exemptions to the face mask rule over the summer but the consequence of having the federal government step in is now requiring them to relent.

American Airlines, after banning medical exemptions in July, is allowing those with a doctor's note and a negative COVID-19 test to eschew the mask while flying. That's provided the note is supplied to the airline's special assistance team beyond 72 hours from boarding and the COVID-19 test is taken within three calendar days of departure or the flyer shows proof of recovery.

The order doesn't regulate exactly how airlines have to accommodate exempted passengers, however, allowing some to impose stricter rules than others. Alaska Airlines banned medical exemptions in August but now has a similar policy to American's and requires flyers seeking an exemption to make accommodations at least five days from their scheduled flights.

Delta Air Lines, alternatively, required passengers claiming an exemption to undergo a virtual screening with an airline-provided medical professional. Flyers would do the screening on the same day as their flight and were advised to arrive extra early to have it done.

Airlines have been requiring masks since the spring as they sought to dampen the threat of asymptomatic spread onboard aircraft. Biden's executive order, however, gives airlines federal backing in enforcing the mask rule and those who don't comply can face civil penalties, according to the Transportation Security Administration.

More than 2,700 passengers have been banned from the skies for mask non-as of mid-January, eight airlines confirmed to Insider. Incidents rose in early January as rioters traveled by plane to Washington, DC to take part in the "Stop the Steal" protests that resulted in the storming of the US Capitol Building.

Alaska Airlines, which devised a soccer-style yellow card system to discreetly remind passengers to wear their masks, had banned 14 passengers on a single flight from Washington to Seattle. And before the protests even began, a Delta flight from Salt Lake City to Washington saw six passengers who had been flouting the mask rule while harassing US Senator Mitt Romney, banned from the airline.

Starting February 2, TSA has begun cracking down on maskless passengers before they even reach the gate.

"Passengers who refuse to wear a mask will not be permitted to enter the secure area of the airport, which includes the terminal and gate area," the agency said in a statement. "Depending on the circumstance, those who refuse to wear a mask may be subject to a civil penalty for attempting to circumvent screening requirements, interfering with screening personnel, or a combination of those offenses."

The Federal Aviation Administration is also stepping in when offenses become egregious, proposing fines of up to $35,000 for those who don't comply.