The safest material for motorcycle helmets is typically considered to be expanded polystyrene (EPS) foam. EPS foam is commonly used as the inner liner of motorcycle helmets because it has excellent impact-absorbing properties. When a helmet experiences an impact, the EPS foam compresses, absorbing and dispersing the force of the impact, which helps protect the rider's head.
In addition to the EPS foam liner, motorcycle helmets often have an outer shell made of materials such as polycarbonate, fiberglass, carbon fiber, or a combination of these materials. These shells provide structural integrity and help distribute the impact over a wider area. The specific material used for the outer shell can vary depending on the helmet's design, purpose, and price range.
It's worth noting that helmet safety is not solely determined by the material used, but also by the helmet's design, fit, and certification standards. To ensure maximum safety, it's important to choose a helmet that meets or exceeds the safety standards set by organizations like the Department of Transportation (DOT), the Snell Memorial Foundation, or the Economic Commission for Europe (ECE).
Always remember to wear a properly fitting helmet when riding a motorcycle as it is one of the most effective ways to protect yourself in the event of an accident.