"That is unacceptable behavior," said Sen. Bernie Sanders (I-VT) said of the American Airlines decision. "They are endangering the lives of the American people."
The hearing featured renewed warnings from Fauci, Redfield and other health experts about the spread of the virus, as some states have tightened Coronavirus restrictions in recent days amid a surge in cases.
"We're seeing significant increases in the southeast and southwest regions of this nation," Dr. Redfield told Senators, who said a combination of increased testing, community spread, and localized outbreaks are all driving the increase.
"We recommend a mask for everyone on the outside," said Dr. Fauci, as he implored Americans of all ages to wear masks when they might come into contact with other people.
"When you're outside and don't have the capability of maintainting distance, you should wear a mask at all times," Fauci added.
The hearing began with a plea from the panel chairman for President Trump to lead the call for masks and face coverings, as an easy way to hold back the virus.
"The President has plenty of admirers," said Sen. Lamar Alexander (R-TN). "They would follow his lead."
But so far, the President has resisted that idea, leaving state and local elected officials to step into that leadership role.