Updated 11/19/15 – 8:31 a.m.

CHICAGO (CBS) — Despite tensions over the possibility of more terror attacks like the one in Paris, some security workers at O’Hare International Airport planned to walk off the job on Thursday to demand better pay.

The workers involved are not Transportation Security Administration officers, but private security workers who perform tasks such as checking the IDs before allowing trucks on the airfield, guarding doors near baggage claim areas and security checkpoints, and patrolling terminals to watch for suspicious activity so they can report it to airport police. TSA officers, who screen passengers, are not part of the walkout

The 160 private security workers have said they want a $15-an-hour wage, and they planned a one-day strike Thursday to protest what they claim are unfair labor practices by their employer, Universal security. They planned to hold a rally at Terminals 2 and 3 at 8 a.m.

SEIU has organized pickets today at half a dozen airports. In other cities, they include ramp workers, baggage handlers, wheelchair attendants, cabin cleaners, terminal cleaners and passenger service workers.

Miltko said that some 2,000 plane cleaners, baggage handlers and other workers will strike at New York’s Kennedy and LaGuardia airports, as well as Newark Liberty, Boston, Philadelphia and Fort Lauderdale.

“We don’t receive enough money to pay the rent,” said Damaso Mejia, a worker involved with the SEIU who cleans and checks plane interiors for suspicious objects at New York Kennedy for $10.10 an hour.

He said he will start working a second job next month and will log 18-hour days to supplement his income.

The workers also have been trying to form a labor union.

“Every time they try to have a voice on the job, or speak out about things, they are retaliated against,” said Izabela Miltko, a spokeswoman for Service Employees International Union Local 1.

Miltko accused Universal Security of penalizing and firing workers who support unionization, retaliating against those who note lapses, and failing to provide proper training.

“Two workers have been fired. Other workers have been retaliated against, and all the workers on the first shift are standing together to fight this retaliation; to stand up, and to try to make our airport more safe,” Miltko said.

The walkout, which has yet to be announced publicly, comes just before air travel picks up for the Thanksgiving holiday. It was not immediately clear if the action would cause flight delays because airlines often have backup plans to avert disruptions.

Reuters reported that the strikers work for companies that U.S. airlines contract for some airport operations. That means pilots, flight attendants and in-house baggage handlers are not taking part in the action.

Workers in Newark started their strike Wednesday night.

Some travelers said they understand why airport workers are striking; but others said they find the timing disturbing, and they’re concerned for their safety.

“I travel a lot for work, and it’s a scary thought,” Michael Goodman said.

Goodman said the strike would only make the wait to get through security at O’Hare even longer.

Fellow travelers Diane Sanders said $15-an-hour isn’t much to ask for.

“Just to live in Chicago, you need to be earning more than that, so I think they should give them their $15,” she said.

Reuters reported the walkout has been in the works since the SEIU sponsored a convention in Washington a month ago for airport workers to discuss their concerns.

Striking workers also planned to hold a news conference in downtown Chicago at 11 a.m.

So far, the walkout did not appear to be causing any flight delays.