Reference: http://wikipedia.org/wiki/Hazard_symbol#Radioactive_sign I needed a radiation warning symbol for a project, and while Thingiverse has a few, none were in OpenSCAD. So as any good hacker, I've thrown one together to aid wherever a scalable and importable warning may.This one is ISO-compliant, though it lacks the standard triangular backing of a sign.Use "use" to import the module from this scad file, and call "Trefoil(,), or just pull the needed code out and use it (that's what OpenSCAD is for after all).