Radioactive Warning Symbol - Official Trefoil Sign for Nuclear Hazards #228542 (License: Personal Use)

This image shows the internationally standardized ionizing radiation warning symbol, commonly called the trefoil, adopted by the IAEA and used globally since 1946. Its design features three equidistant yellow blades radiating from a central circle on a black background to maximize visibility and convey immediate hazard. The symbol is mandated on containers, doors, equipment, and signage where radioactive sources are stored or used.

Used in nuclear facilities, medical imaging labs, research centers, and transport packaging to warn personnel and the public of radiation risks; matches user intent for safety education, regulatory compliance, or hazard identification resources.