Helmets

Helmets are protective head coverings designed to absorb impact and reduce the risk of head injury in various activities. They consist of a hard outer shell, an energy-absorbing liner, and a retention system to secure the helmet on the head. The outer shell is typically polycarbonate, fiberglass, or carbon fiber, while the liner is usually expanded polystyrene foam. Some helmets incorporate additional comfort padding, ventilation, and face shields.

Helmets are used in a range of settings, including cycling, motorcycling, equestrian sport, ice and field hockey, American football, construction and mining, firefighting, and military applications. The design and intended use determine protective standards and certification. For example, bicycle helmets in the United States must meet CPSC safety standards; European bicycle and skate helmets are tested to EN 1078; motorbike helmets follow a variety of standards such as ECE 22.05/22.06, DOT, or Snell certifications. Sports helmets may also meet Snell, ASTM, or NOCSAE standards.

Historically, helmets evolved from metal headgear in antiquity to specialized safety devices in industrial settings, with modern helmets featuring energy-absorbing foams and lightweight composites.

Maintenance involves regular inspection for cracks, dents, loosening straps, or compromised padding, and replacement after a heavy impact or after a recommended lifespan, typically several years depending on use and manufacturer guidelines.

While helmets substantially reduce the risk of head injury, they are not foolproof and should be used in combination with appropriate protective gear and safe practices.