According to national standards, qualified fiberglass safety helmets can withstand considerable impact forces. In the impact absorption performance test, it is required that the force transmitted to the wearer's head by the safety helmet after being subjected to impact force shall not exceed 4900 Newton (approximately 500 kilogram force). This means that fiberglass safety helmets need to have the ability to effectively disperse and absorb impact forces exceeding this value during design and manufacturing.

When impacted, the shell of the fiberglass safety helmet comes into play first. The arc-shaped design of the cap shell can distribute the impact force to the entire surface of the cap shell, avoiding the concentration of impact force on a certain point. At the same time, the high-strength characteristics of fiberglass material enable the cap shell to withstand significant pressure without breaking. The composite structure of glass fiber and resin absorbs some energy through its own stretching and deformation when subjected to impact, while the resin plays a role in bonding and transmitting stress, enabling the entire cap shell to work together and resist the impact force.

The lining of the hat is also an important part of resisting impact force. There is a certain buffer space between the cap liner and the cap shell. When impacted, the cap liner will compress with the deformation of the cap shell, absorbing the impact force through compression deformation. The material of the hat lining usually has good elasticity and cushioning properties, such as sponge, rubber, etc., which can absorb most of the energy before the impact force is transmitted to the head. Through the dual buffering and absorption of the cap shell and cap liner, the impact force transmitted to the head can be controlled within a safe range, effectively protecting the head from injury.