There is a massive difference between a gamma source that emits so much radiation the sources can be (infamously) engraved with "DROP AND RUN" that will give a

There is a massive difference between a gamma source that emits so much radiation the sources can be (infamously) engraved with "DROP AND RUN" that will give a lethal dose in tens of minutes to someone close enough to read the text...and a tiny little layer of an alpha-emitting material embedded in a piece of gold foil.