In NFPA (National Fire Protection Association) labels, the blue color specifically signifies health hazard risks. This system uses a color-coded numbering system where each color represents a different type of hazard related to materials or substances.
For example, a blue label might indicate how harmful a material could be to human health if exposed during handling or an incident. The scale typically ranges from 0 to 4, with 0 indicating no hazard and 4 indicating a severe health risk, which helps responders quickly assess the level of danger posed by a material in emergency situations.
In contrast, the other colors signify different hazards: the red color denotes fire hazards, the yellow indicates reactivity hazards, and other colors could represent additional types of hazards. The clear distinction among these colors allows for rapid identification of various risks associated with hazardous materials on-site.