An emergency response drill at Newark Liberty International Airport Saturday morning might raise some passengers’ pulses as simulations produce some smoke and emergency vehicles respond.

“We’re conducting a full-scale emergency response exercise today (Sept 14th) for 2-3 hours starting at 10 a.m.,” the airport’s official Twitter account posted. The drills will not have any impact on flights, the post said, “but you may see emergency vehicles, simulated passenger injuries, and simulated smoke during the exercise.”

The Port Authority said in a press release the exercise will focus on “mutual aid response” training, or coordinating between airport personnel and local emergency response organizations.

Newark was the scene of pandemonium on Labor Day when an Alaska Airlines employee who had an issue with her medication for bipolar disorder sparked a near stampede as she aggressively questioned two Asian travelers.