Workplace hazards may involve heavy machinery, fire, chemicals or traffic. In 1970, the Occupational Health and Safety Act (OSHA) was passed with the goal of sending every worker home healthy and safe at the end of the workday. OSHA makes use of color coding to help workers identify and safely react to hazards.
Red may be the most widely recognized color for indicating hazards. OSHA regulations state that red should be used to mark the location of fire-extinguishing and protective equipment and to identify containers of flammable liquids. Barricades and temporary obstructions must be marked with red flashing lights. Red also designates emergency stop buttons, switches and bars on hazardous and heavy equipment.
According to OSHA, yellow warns workers to proceed with caution, similar to a yield traffic sign. Yellow also designates physical hazards such as tripping and falling.
Orange indicates dangerous parts of equipment, such as areas where body parts can become caught in machinery, or swinging pieces that can hit someone in the course of operation.
OSHA dictates that equipment be marked with blue if it is in need of or currently under repair, in order to prevent further damage to the equipment or harm to the workers.
Green indicates first aid or other safety equipment that is not used in the prevention or extinguishing of fires. This equipment includes safety gear for employees working from heights and respirator masks.
Purple marks radioactive materials or equipment.