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National Fire Protection Association Hazard Identification System

The National Fire Protection Association (NFPA) developed a hazard identification system for emergency responders that is still in use today. In the past some chemical manufacturers used NFPA diamonds on their products, but now labels are required to use GHS labeling. This section briefly explains the NFPA system.

The NFPA diamond provides a quick visual representation of the health hazard, flammability, reactivity, and special hazards that a chemical may pose during a fire.

The NFPA diamond consists of four color-coded fields: blue, red, yellow, and white. The blue, red, and yellow fields—which represent health hazard, flammability, and reactivity, respectively—use a numbering scale ranging from 0 to 4. A value of 0 means that the material poses essentially no hazard, whereas a rating of 4 indicates extreme danger. The white field is used to convey special hazards.

Note: The numbering system in the NFPA Hazard Identification System and the numbering system in the GHS are opposite; higher values in the NFPA system indicate higher hazards, and the opposite is true for the GHS.

It must be understood that the NFPA system was designed to convey safety information to emergency first responders, such as fire fighters. It was not designed to notify the user of the hazards of chemicals in the laboratory setting. Additional information must be available, such as GHS symbols and Safety Data Sheets.

NFPA Diamond (with four colors - blue, red, yellow and white)

NFPA Hazard Identification System


BLUE Diamond Health Hazard
  • 4 Deadly
  • 3 Extreme Danger
  • 2 Hazardous
  • 1 Slightly Hazardous
  • 0 Normal Material
RED Diamond Fire Hazard (Flash Point)
  • 4 Below 73 °F
  • 3 Below 100 °F
  • 2 Above 100 °F
    Not Exceeding 200 °F
  • 1 Above 200 °F
  • 0 Will Not Burn
YELLOW Diamond Reactivity
  • 4 May Detonate
  • 3 Shock and Heat; May Detonate
  • 2 Violent Chemical Change
  • 1 Unstable if Heated
  • 0 Stable
WHITE Diamond Special Hazard
  • ACID – Acid
  • ALK – Alkali
  • COR – Corrosive
  • OXY – Oxidizer
  •  – Radioactive
  • – Use No Water


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