What color is used in the NFPA system for indicating health hazards?

In the NFPA (National Fire Protection Association) labeling system, the color blue is specifically designated for indicating health hazards. This is an important aspect of the NFPA labeling system, which uses a diamond shape divided into four quadrants, each representing different types of hazards: health, flammability, reactivity, and special hazards.

The blue section of the diamond communicates the potential health risks posed by a substance, with a numerical scale from 0 to 4 indicating the severity of the hazard, where 0 signifies no hazard and 4 indicates a very high hazard. This color coding assists emergency responders in quickly assessing the potential risks associated with a substance during incidents, thereby enabling them to make informed decisions regarding safety measures and response actions. Understanding the meaning behind the colors in the NFPA system is critical for effective hazard communication in emergency situations.