Radioactive trefoil symbol

This page is about the meaning, origin and characteristic of the symbol, emblem, seal, sign, logo or flag: Radioactive trefoil symbol.

Image of the Radioactive trefoil symbol

The international radiation symbol (also known as trefoil) first appeared in 1946, at the University of California, Berkeley Radiation Laboratory.

At the time, it was rendered as magenta, and was set on a blue background. The modern version used in the US is magenta against a yellow background, and it is drawn with a central circle of radius R, an internal radius of 1.5R and an external radius of 5R for the blades, which are separated from each other by 60°. The trefoil is black in the international version, which is also acceptable in the US.

Graphical characteristics:
Symmetric, Closed shape, Colorful, Contains both straight and curved lines, Has no crossing lines.

Category: Hazard Symbols.

More symbols in Hazard Symbols:

Hazard symbol are recognizable symbols designed to warn about hazardous materials, locations, or objects, including electric currents, poisons, and other things. The use of hazard symbols is often re… read more »

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