Starting at 1 p.m. on Saturday, Concourse G will close and about a dozen departing flights will be moved to nearby terminals.
According to the AFGE, the TSA once had a workforce of around 47,000 dealing with 740 million passengers a year, but now has 44,000 workers servicing 851 million passengers a year. Many workers have been furloughed, whereas some remain on the job without pay.
"Right now, there's approximately some 40 employees that are calling in sick from TSA", meaning that "this terminal doesn't have the manpower to accommodate all the passengers", airport spokesman Jack Varela told Agence France-Presse.
TSA has downplayed reports that a rise in airport screeners calling out sick - or even quitting their jobs - has led to long lines at security.
"We asked for expedited hearing with a temporary restraining order", said Mick Devine, the New England Regional Vice President of the National Air Traffic Controllers Association.
In Atlanta, numerous TSA agents that serve the nation's busiest airport are feeling the pinch.
With the shutdown, TSA employees and other staffers considered crucial to safety and security are working without pay.
Bilello said the TSA is working with stakeholders and industry partners to look at efforts to consolidate officers and operations. The percentage of TSA workers who called in sick on Thursday was 5.1 percent, compared to a 3.3 percent unscheduled absence rate on the same day previous year, TSA spokesman Michael Bilello said in a Tweet.
In 2016 when TSA was understaffed at many airports, creating lines long enough to make many travelers miss their flights other airports explored hiring contractors.
- Federal employees in the Bay Area are feeling the pinch of the shutdown by not receiving their paychecks.
Seattle-Tacoma International Airport organized an event with credit unions, utilities and nonprofit organizations that can help federal employees obtain short-term loans and assistance, said spokesman Perry Cooper.
Asked about the plight of those going without pay, the president shifted the focus, saying he felt badly "for people that have family members that have been killed" by criminals who came over the border.
The Miami International Airport is temporarily closing one terminal because a number of workers aren't coming to work while they aren't getting paid.
In a before a federal court in Washington, DC the NTEU is arguing that the 1982 Antideficiency Act - under which the government shutdowns happen when Congress fails to appropriate funding for federal programs - is itself unconstitutional because it allows the executive branch to compel employees to work in emergencies.