Hard hats are protective headgear worn in construction and industrial settings to prevent head injuries from falling or flying objects. They were first developed during the 19th century Industrial Revolution as buildings were being constructed taller. A variety of equipment used on construction sites like cranes, drills, and building materials pose head injury risks. Wearing hard hats is now mandatory for workers in environments with overhead hazards like construction and mining sites due to past injuries and deaths from unprotected head impacts. Modern hard hats are optimized for comfort, visibility, and durability to improve worker safety.