Skull and Crossbones
Universal symbol for poison, toxic substances, and mortal danger.
International · c. 1400 CE – present
Biohazard Symbol
Symbol warning of biological substances that pose a threat to living organisms.
Description
The biohazard symbol was designed in 1966 by a team at Dow Chemical Company led by Charles Baldwin. The design was chosen through a study to be memorable, unique, and meaningless (so it could be learned as a warning sign without prior cultural associations). The symbol consists of three interlocking circles arranged around a central ring, creating a trefoil-like shape. It is used to label biological substances that pose a threat to living organisms, including infectious agents, toxins, and biological waste. ISO 7010 includes it as warning sign W009.
Origin & Cultural Context
Designed in 1966 by Charles Baldwin and colleagues at Dow Chemical Company, published in Science magazine in 1967.