The basic structure of protective footwear typically includes the toe cap (steel or composite material), the upper, the lining, the insole, and the outsole.
The toe cap is the core component for impact protection, and its material directly determines the protection level. Steel toe caps meet AN1 and AN2 standards; aluminum alloy toe caps are generally suitable for AN1 protection; and composite toe caps can meet AN2 protection standards.
Upper materials must balance protection, durability, and comfort. Based on material composition, footwear is categorized into Class I (made of leather or other materials) and Class II (made entirely of rubber or polymeric materials).
Sole materials directly influence properties such as slip resistance, wear resistance, oil resistance, and electrical insulation. Common materials include natural rubber, polyurethane (PU), thermoplastic polyurethane (TPU), PVC, and EVA. Rubber soles offer excellent wear resistance and grip but lack high-temperature resistance; PU soles provide good slip resistance, are lightweight, and resist chemical corrosion; PVC is inexpensive but has poor elasticity. Slip resistance depends not only on the sole material but also significantly on the tread pattern design. Under identical surface conditions, zigzag tread patterns offer superior slip resistance compared to transverse or longitudinal patterns, while cleat-like patterns provide excellent grip. Wider tread patterns oriented at 0° or 45° angles yield higher coefficients of friction and better slip resistance. Tread wear severely compromises slip resistance; a worn-down, smooth sole loses its ability to channel away fluids, resulting in a significant loss of grip.