What color on the NFPA 704 placard indicates reactivity?

The NFPA 704 placard is a standardized color-coded system used to communicate the hazards of materials, particularly in emergency situations. The color that indicates reactivity on this placard is yellow. This color is specifically designated for reactivity hazards, which refer to the potential for a substance to undergo a chemical reaction under certain conditions, possibly leading to hazardous situations such as explosions or the release of toxic gases.

Each of the other colors on the NFPA placard corresponds to different types of hazards. Red indicates flammability, blue signifies health hazards, and white is used for special hazards. Understanding this color-coded system is crucial for safety personnel and first responders as it helps them assess the risks associated with materials they may encounter and take appropriate precautions while handling or responding to incidents involving those materials.