What does the yellow color in the NFPA label represent?

The yellow color in the NFPA (National Fire Protection Association) label specifically represents reactivity hazards. This section of the label uses a numerical scale from 0 to 4, where 0 indicates that the material is stable and poses no risk of reactivity, and 4 indicates a high level of reactivity that may cause explosions or violent reactions under normal conditions. Understanding this aspect of the NFPA label is crucial for safety in handling various materials, as it helps responders and workers identify potential hazards associated with chemical substances in their operational environment.