Generally applies to footwear providing toe protection for the wearer. Safety-toe footwear has been divided into three classifications: 75, 50, and 30; based on its ability to meet the minimum requirements for both compression and impact as specified by the American Standard Z41 Series. Generally, the safety-toe shoe should be used for work requiring the handling of heavy materials. Safety shoes may also be obtained with conductive soles to drain off static charges, and with nonferrous construction, to reduce the possibility of friction sparks in environments with a fire or explosion hazard. Other safety shoes are designed to provide protection against splashes of molten metal, construction hazards such as protruding nails, contact with energized electrical equipment, wet conditions, hot surfaces, and other hazards.