In NFPA 704 (diamond), what does the yellow represent?

In the context of the NFPA 704 system, which is a standard for identifying the hazards of materials through a color-coded diamond, the yellow section specifically represents instability. The yellow quadrant assesses the reactivity of the material, indicating how likely it is to undergo a violent reaction or explosive decomposition under specific conditions. A higher number in this section signifies greater instability and potential hazards in handling or storage situations.

Understanding the significance of the yellow section is crucial for emergency responders and safety professionals, as it helps determine the appropriate precautions and emergency strategies required when dealing with potentially unstable materials. This includes recognizing situations where materials may react with other substances, leading to dangerous scenarios.