NFPA 704

NFPA 704 ex

The Standard System for the Identification of the Hazards of Materials for Emergency Response is a hazard identification system developed by the National Fire Protection Association (NFPA) in the United States. The system, commonly known as NFPA 704 or the NFPA Diamond, provides a readily recognized and easily understood method for identifying specific hazards and their severity. It addresses the health, flammability, instability, and related hazards that may be presented as short-term, acute exposures most likely to occur as a result of fire, spill, or similar emergency situations.

NFPA 704 Diamond

The NFPA 704 Diamond is a visual representation of the hazard identification system, consisting of a square divided into four smaller squares. Each smaller square represents a specific hazard category and is color-coded as follows:

• Blue: Health hazards
• Red: Flammability hazards
• Yellow: Instability hazards
• White: Special hazards

Each colored square contains a number from 0 to 4, indicating the severity of the hazard within that category, with 0 representing no hazard and 4 representing the most severe hazard.

Health Hazards

The blue square in the NFPA 704 Diamond represents health hazards. The numerical rating indicates the risk associated with exposure to the material:

• 0: No significant health hazard
• 1: Slight hazard, causing irritation or minor reversible injury
• 2: Moderate hazard, causing temporary incapacitation or residual injury
• 3: Serious hazard, causing serious or permanent injury
• 4: Severe hazard, causing life-threatening or potentially fatal injury

Flammability Hazards

The red square in the NFPA 704 Diamond represents flammability hazards. The numerical rating indicates the likelihood of the material to ignite and burn:

• 0: Will not burn
• 1: Must be preheated for ignition
• 2: Ignites when moderately heated
• 3: Ignites at normal temperatures
• 4: Extremely flammable and readily vaporizes at normal temperatures

Instability Hazards

The yellow square in the NFPA 704 Diamond represents instability hazards. The numerical rating indicates the potential of the material to react, decompose, or explode:

• 0: Stable and not reactive with water
• 1: Unstable if heated or mixed with water
• 2: Violent chemical change or decomposition with heating or high pressure
• 3: Capable of detonation or explosive decomposition with strong initiation or heating under confinement
• 4: Readily capable of detonation or explosive decomposition at normal temperatures and pressures

Special Hazards

The white square in the NFPA 704 Diamond represents special hazards, which are indicated by specific symbols:

• W: Reacts with water in a hazardous manner
• OX: Oxidizer, capable of contributing to the combustion of other materials
• SA: Simple asphyxiant gas

National Fire Protection Association (NFPA): NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response

External Links

• Occupational Safety and Health Administration (OSHA): Hazard Communication Standard
• U.S. Environmental Protection Agency (EPA): Emergency Planning and Community Right-to-Know Act (EPCRA)
• Centers for Disease Control and Prevention (CDC): Chemical Safety

See Also

• Hazard Communication Standard
• Globally Harmonized System of Classification and Labelling of Chemicals (GHS)
• Material Safety Data Sheet (MSDS)
• Safety Data Sheet (SDS)