TSA Administrator David Pekoske has approved a one-time $500 award for each uniformed TSA screening officer, utilizing "unique authorities provided TSA in law." The award is equivalent to about four days' pay for many officers. It's essentially a performance bonus for the holiday season.

The government entered its fourth week of a partial shutdown on Saturday, officially making it the longest shutdown in American history. Around 800,000 federal employees have been furloughed or are working without pay. As TSA screeners are considered "essential," they have been working without pay since the shutdown started on December 22.

The government entered its fourth week day of a partial shutdown on Saturday, officially making it the longest shutdown in American history. Around 800,000 federal employees have been furloughed or are working without pay. As TSA screeners are considered "essential," they have been working without pay since the shutdown started on December 22.

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The bonus is "in recognition of their hard work during yet another busy holiday travel season, maintaining the highest of security standards during an extraordinary period," Pekoske wrote on Twitter.

The $500 award, as well as payment for those who worked on December 22, should appear in screeners' accounts in the next few days.

One TSA official compared the agency's efforts to find any available means to push payments out to officers to looking for loose change under cushions. There is a clear sense of frustration at TSA headquarters over the situation, given that the shutdown substantially limits the options to pay essential staff who are working.

The number of TSA employees are calling in sick is on the rise. Miami International Airport closed one of its concourses in the afternoons this weekend as a "precautionary measure" after TSA officers' sick calls doubled during the week. Federal employees are not permitted to strike by law.

While screening times have stayed relatively consistent nationally, sick calls climbed higher on Saturday -- up 70 percent from the same day a year ago. Still, more than 94 percent of staff reported as scheduled.

Assistant Administrator for Public Affairs Michael Bilello tweeted a statement Saturday "security standards remain uncompromised at our nation's airports," despite the sick calls.

"Nationwide, TSA screened 1.96 million passengers yesterday ... 99.9 percent of passengers waited less than 30 minutes; 95 percent of passengers less than 15 minutes," he said.

However, TSA leaders remain worried about a national "tipping point," when screeners look elsewhere for work.

"It's profoundly unfair and almost disrespectful to put us in the middle of this debate over border security when we have absolutely nothing to do with it," TSA officer Mike Gayzagian told CBS News.