What hazard level does the yellow color represent in the labeling system?

In the labeling system, the yellow color specifically indicates the instability hazard level. This classification reflects the potential risk associated with the stability of a chemical compound. A rating of 4 (severe) signifies that the substance is highly unstable and poses a significant danger, potentially leading to explosive reactions or other violent incidents under certain conditions, such as temperature changes or the presence of water.

The other categories represented in the labeling system each use different colors. Health hazards, flammability hazards, and special hazards have their own distinct representations, making it crucial to understand that yellow corresponds specifically to instability hazards. This distinction is essential for safe handling, storage, and transportation of chemicals, ensuring that individuals recognize the unique risks presented by materials with high instability ratings.