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NFPA chemical hazard labels

The National Fire Protection Association (NFPA) has developed a system for indicating the health, flammability and reactivity hazards of chemicals. In addition, a special precaution symbol may be used where necessary.

Scroll down the page for general information on the NFPA diamond labeling symbol.

Rating Summary

Health (Blue)

  4 Danger May be fatal on short exposure. Specialized protective equipment required
  3 Warning Corrosive or toxic. Avoid skin contact or inhalation
  2 Warning May be harmful if inhaled or absorbed
  1 Caution May be irritating
  0 No unusual hazard  

Flammability (Red)

  4 Danger Flammable gas or extremely flammable liquid
  3 Warning Flammable liquid flash point below 100° F
  2 Caution Combustible liquid flash point of 100° to 200° F
  1 Combustible if heated  
  0 Not combustible  

Reactivity (Yellow)

  4 Danger Explosive material at room temperature
  3 Danger May be explosive if shocked, heated under confinement or mixed with water
  2 Warning Unstable or may react violently if mixed with water
  1 Caution May react if heated or mixed with water but not violently
  0 Stable Not reactive when mixed with water

Special Notice (White)

  W Water Reactive
  Oxy Oxidizing Agent


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