What does the color blue indicate on a warning label?

The color blue on a warning label is used to indicate a health hazard. This is part of the labeling system in chemical safety, particularly in the context of the National Fire Protection Association (NFPA) labels or similar hazard communication systems.

Health hazards can include a range of dangers such as toxicity, corrosiveness, and irritants that pose risks to human health. By using blue to signify health hazards, individuals can quickly identify and understand the potential risks associated with a specific chemical or material, allowing them to take appropriate safety precautions when handling it.

In contrast, other colors represent different types of hazards: red typically indicates fire hazards, yellow represents reactivity hazards, and sometimes other colors are used for specific types of risks, such as radiation. Knowing the meaning of these colors is essential for safe practices in environments where hazardous materials are present.