The federal government shutdown is taking its toll on the nation's airports, the people who work there and millions of passengers.

Security checkpoints have been shut down at some U.S. airports, the latest being George Bush Intercontinental Airport in Houston. There was a similar situation at Miami International Airport over the weekend.

"That's a security concern," AJ Dhingra said before boarding a plane Monday at John F. Kennedy International Airport in Queens.

There has been a large increase in Transportation Security Administration agents calling out sick after not receiving a paycheck because of the government shutdown. According to TSA numbers, there is currently a 7.6 percent rate of unscheduled absences nationally, compared to 3.2 percent a year ago.

But the TSA says security standards remain uncompromised. Just like TSA agents, air traffic controllers are essential government employees who must report to work, even without pay.

Kevin Maney works at New York terminal radar approach control, or TRACON, in Westbury. He says despite the strain on their wallets, travelers should not worry about their safety.

"We have a professional, dedicated workforce who have been coming to work even though they are not getting paid," he says.

If the shutdown continues, Maney says he is worried about days where they do see an increase in air travel like the Super Bowl. Randy Brown, another employee, says the workers are basically being held "hostage."

A bill that would guarantee back pay for all federal workers passed the U.S. House and Senate. It awaits the president's signature.

Monday marked the 24th day of the shutdown, which has become the longest in U.S. history.