Which NFPA 704 color indicates health hazards?

• A. Red
• B. Yellow
• C. Blue
• D. White

Answer: (C)

The color blue in the NFPA 704 labeling system specifically indicates health hazards associated with hazardous materials. This system uses a diamond-shaped label that is divided into four quadrants, each representing a different type of hazard. The blue section is dedicated to health risks, with a numerical scale from 0 to 4 indicating the severity of the health risks posed by the material.

A rating of 0 means that the material poses no health risk, while a rating of 4 signifies a severe risk that could cause fatal exposure. Therefore, the blue color serves as a quick visual reference to assess the potential health dangers when encountering hazardous substances, enabling responders and handlers to take appropriate precautions and protective measures. Understanding this color coding is crucial for anyone involved in emergency response, ensuring that they can recognize and address health hazards efficiently and effectively.