The NFPA 704 diamond system provides a readily recognized, easily understood system for identifying specific hazards and their severity using spatial, visual, and numerical methods to describe in simple terms the relative hazards of a material. These placards act as an immediate warning system for emergency service personnel, addressing health, flammability, instability, and related hazards that may be present, acute exposures that are most likely to occur as a result of fire, spill, or similar emergencies.