The trefoil, the traditional international warning symbol for radiation. Source: Wikipedia.
The yellow and black “trefoil” is familiar to many of us as a warning symbol for radiation or radioactive materials. It is used internationally and is well-established. Yet there is nothing inherent in the symbol to suggest either radiation or danger, aside perhaps from the yellow color used. If one has not been educated about what the symbol represents, it will be meaningless to him.
The new, supplementary warning symbol. Source: IAEA.
As a result, New Scientist reports, the International Atomic Energy Agency is adding a new symbol to supplement the old one. This symbol incorporates the trefoil, but also shows it leading to a skull and crossbones, signifying death, as well as a person running away. The IAEA’s tests suggest that people could easily understand the danger it was conveying.
At first glance, it appears a bit extreme. This is not a replacement, though. The IAEA states
The symbol is intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury, including food irradiators, teletherapy machines for cancer treatment and industrial radiography units. The symbol is to be placed on the device housing the source, as a warning not to dismantle the device or to get any closer. It will not be visible under normal use, only if someone attempts to disassemble the device. The symbol will not be located on building access doors, transportation packages or containers.