The recent Amtrak train that derailed in North Carolina after slamming into a tractor-trailer comes on the heels of two other train crashes in February. Despite these high-profile accidents, both passenger and freight train accidents have been declining over the past decade.

Allan Zarembski is a derailment and train safety expert and director of the University of Delaware's Railroad Engineering and Safety Program. He says that there are three kinds of train accidents: derailments and train collisions, grade crossings (like the North Carolina and February incidents) and trespassing.

Zarembski tells Here & Now's Robin Young that at every railroad crossing, there is, by law, an emergency phone number posted that should be called if a vehicle is stuck on the tracks.