TUESDAY TRIVIA: What Is the Purpose of the Black Rails on the Sides of School Buses?

A long-time bus driver has revealed the purpose for the black rails, called rub rails, on the sides of school buses.

First, they function as an extra layer of protection for the thin walls of the bus, helping absorb the force of a collision.

Rub rails are also positioned at specific spots. The lowest one is installed at floor level, the middle one corresponds to the bottom of the seats, and the top one usually matches the height of the top of the seats and/or the bottom of the window. “In the event of an accident they actually give firefighters an idea of where to cut,” he explains.

Rescue workers would also be able to tell where the impact occurred. If it’s below the bottom rail—i.e. below the floor—bus passengers may have avoided the worst of the crash.