A helmet is a form of protective headgear worn when riding horses. Equestrian helmets are specially designed to protect the rider’s head during falls off of a horse under any circumstances, especially landing on a hard object or being struck by the horse's hoof. Certified helmets are required headgear for many competitive riding events. The FEI rules require that helmets used at FEI events “are in compliance with the applicable international testing standards”. For Eventing the requirements are more specific, with a list of accepted standards (European (EN), British (PAS), North American (ASTM), Australian/New Zealand).