Radioactive Warning Symbol - Meaning, History, and Safety Significance #281410 (License: Personal Use)

This is the internationally recognized ionizing radiation warning symbol, commonly called the trefoil, consisting of three black blades arranged at 120-degree angles around a central circle, set against a vivid yellow background with a black outer ring. Designed in 1946 at the University of California, Berkeley, it was standardized by the IAEA and adopted globally to alert individuals to radiation hazards in labs, nuclear facilities, medical imaging, and transport. Its high-contrast color scheme ensures visibility and immediate recognition, even from a distance or under poor lighting.

Used on signage, equipment labels, packaging, and safety documentation in nuclear energy, healthcare (radiology/oncology), research labs, and hazardous material transport; matches user intent for hazard awareness, safety compliance, or educational reference.