Codes and standards published by NFPA are displayed as read-only under license from NFPA solely for use within this system. NFPA material may not be downloaded, printed, reproduced, or transferred.

NFPA 704 presents a system to simplify determining the degree of health, flammability and instability hazards of chemicals. The system also provides for the recognition of unusual water reactivity and oxidizers. The NFPA 704 ratings are displayed in markings that are commonly referred to as the "NFPA hazard diamond".

The 2001 edition clarifies numerous topics...
-Rating of mixtures
- Three options for how to rate areas with multiple chemical storage and use
- Location of signs
- More quantitative criteria for flammability ratings for solids
- Quantitative criteria for a flammability rating of zero, including introduction of a new method.

Plus adds important information, including...
- Guidance material for quantifying the degree of water reactivity
- An entire annex for water reactivity identification criteria
- Expanded data on flash point test methods.