People may think they can stand alongside tracks and be safe from a train, but the truth is trains are wider than the tracks. A train can extend three or more feet on either side of the steel rail, so the safe zone for pedestrians is well beyond three feet on either side.

A train is significantly wider than the tracks it runs on, a design necessity for stability, interior space, and aerodynamic efficiency. In the United States and most of Europe, the standard gauge (the distance between the inner sides of the rail heads) is exactly 4 feet 8.5 inches (1,435 mm). However, a standard passenger train car is typically between 9 feet and 10.5 feet wide. This means the train body overhangs the tracks by roughly 2 to 3 feet on each side. This "overhang" is carefully calculated by engineers to ensure that the center of gravity remains low and stable, even when the train is leaning into curves at high speeds. The difference between the track width and the vehicle width is known as the "loading gauge," which defines the maximum height and width of the train to ensure it can safely pass through tunnels, under bridges, and alongside station platforms. If a train were only as wide as its tracks, it would be extremely prone to tipping over and would offer very little room for passengers or freight, making modern rail transport physically and economically impossible.