For example, the United States requires a height of 14 feet (4.27 m) for highway bridges.
In much of the United States, the maximum height of a semi truck, in the absence of an approved overheight permit, is 13 feet, 6 inches (4.12 m).
Accidents involving these bridges have spurred mitigation efforts, such as installing sensors and signs that warn drivers.
[4] Viral videos of bridge strikes have generated substantial public interest.
[5][6] One of the most famous examples of this is the Norfolk Southern–Gregson Street Overpass, also known as the "11foot8" bridge, which was popularized by a YouTube channel.