The “Fire Diamond” or “NFPA 704” refers to signs posted at locations that contain hazardous materials. The purpose of the signs are to alert emergency personnel to the risks posed by the materials.
The term, “NFPA 704,” refers to the specific “Standard System for the Identification of the Hazards of Materials for Emergency Response,” which is a standard maintained by the National Fire Protection Association (U.S.A).
The four divisions of the sign are typically color-coded with:
* Red, indicating flammability (0-4)
* Blue, indicating level of health hazard (0-4)
* Yellow, for chemical reactivity (0-4)
* White containing instructions for special hazards
Each of the “flammability,” “health,” and “reactivity” sections are rated on a scale from 0 (no hazard) to 4 (severe risk).
The white part of the sign may have special instructions that refer to specific circumstances in the vicinity. For example, there might be an instruction that means “dangerous gases” are present or another that states “don’t use water” due to certain chemicals.
Emergency responders refer to these signs to determine what, if any, special equipment should be used, or procedures to be followed, or precautions to be taken, during the initial stages of an emergency response.