If you're trapped in a vehicle that's quickly filling up with water, breaking a window to escape might be much tougher than you think.
One third of new cars have side windows that are as hard to break as front windshields. Knowing what type of window you have could be critical in an emergency.
A video captured by an Austin police officer shows the last-minute rescue of three women and a dog. They were trapped on a bridge over Williamson Creek and their car was quickly filling with water. Two officers pulled them to safety one minute before the car was swept off the bridge. It's that type of flooding that has safety experts warning drivers about a just-exposed problem.
"It's so important for you to understand what type of windows you have," said Daniel Armbruster with AAA Texas.
That's because a driver who gets trapped in a submerged car could be counting on a vehicle escape tool to get out. One easy strike with a hammer-style tool and the tempered glass that has typically been used for side windows shatters, creating an emergency exit.
But new research from AAA shows many car manufacturers are replacing tempered glass with much stronger laminated side windows.
"Right here on the label it says Lamisafe and that means that's laminated glass," said Armbruster as he pointed to a label on the bottom corner of a side window. "Laminated is simply taking two sheets of tempered glass and putting a solid piece of clear plastic between them, bonding them together to make them much stronger."
A recent study by AAA shows the laminated glass in side windows is nearly unbreakable. It's the same type of glass that's been used in windshields for decades.
"Vehicle escape tools cannot break through these laminated windows," said Armbruster.
To test the difference between tempered glass and laminated glass CBS Austin went to the Budget Wrench-A-Part Salvage Yard in Belton, Texas.
A crew lined up junked cars with both types of windows, so we could try to break them with the two most common types of vehicle escape tools.