At a Senate hearing on the Trump administration’s coronavirus response June 30, Sen. Bernie Sanders (I-VT) said American Airlines was “endangering” the American people.

Sanders comments came as he questioned Dr. Robert Redfield, director of the CDC, about American Airlines release of middle seats for booking, which the airline announced in a press release on increased cleaning protocols June 26.

Redfield said the CDC was “disappointed” when they heard about American’s decision.

"This is under critical review by us at the CDC. We don't think it's the right message," Redfield said. "Again, we think it's really important – whether it's on a bus or a train or a plane – that individuals are social distancing to a degree that's feasible, and at least, have a reliable face covering.”

Sen. Tammy Baldwin (D-WI) said that with some businesses practicing social distancing and others not, there was no “level playing field,” and some businesses would suffer economically for adhering to CDC social distancing guidelines.

She asked the agency and governmental officials to create an “emergency temporary standard” of governance regarding issues like masks, best practices and social distancing.

American Airlines is not the only carrier to open middle seats for booking. Air Canada has announced that it will do the same. United is also unblocking middle seats, although both United and American say they will notify customers when flights are full.

By contrast, Delta Air Lines, Southwest and JetBlue continue to block middle seats for social distancing, although that may change in time.

An “emergency temporary standard” of social distancing would mandate that middle seats continue to be blocked on increasingly filled flights until instances of COVID-19 reached consistently lower levels.