As we currently know it, the three-bladed radiation warning symbol was allegedly created at the University of California Radiation Laboratory in Berkeley around 1946. A letter written in 1952 by Nels Garden, Head of the Health Chemistry Group at the Radiation Laboratory suggests that the symbol was meant to represent radiation emitting from an atom.
Various versions of the symbol were used until in the 1950’s ANSI Standards and United States Federal Regulations had specified the version with which we are currently familiar. The use of black and yellow is a common colour combination for danger and is believed to originate from the colour code of the stinging bee and wasp. Various other theories regarding the inspiration for the design range from “Dangerous Ship Propellers” to the bomb aiming sights on board the Enola Gay – the airplane that dropped the first atomic bomb.
Whatever its inspiration, it remains a feared and powerful symbol that can still be found in almost every office in the world. Just look at your nearest smoke detector and almost certainly – if you were to open the casing which you shouldn’t – you will find this symbol inside … along with a warning about the correct disposal of radioactive material. We bet that you didn’t know that little bit of information.