Which symbol is commonly used to indicate a biological hazard?

The biohazard symbol is widely recognized as the standard indicator for biological hazards. This symbol consists of three interlocking circles, often depicted in a vivid orange or yellow background, which effectively communicates the presence of potentially harmful biological materials, such as pathogens, viruses, or toxins that can pose health risks to humans and the environment.

Its usage is crucial in laboratory settings, medical facilities, and during the handling of infectious agents to ensure safety and awareness among personnel. The symbol's design is distinct and meant to capture immediate attention, helping to prevent accidental exposure or misuse of biological materials.

In contrast, other symbols mentioned, such as the caution triangle or the skull and crossbones, signify different types of hazards. The caution triangle is more general and typically warns of potential hazards without specific reference to biological risks. The skull and crossbones is associated with toxic substances but does not specifically indicate a biological threat. The bacteria emblem is not an official symbol used for hazard communication. Therefore, the biohazard symbol is the most appropriate and widely accepted indicator for biological hazards.