Can radiation be passed from person to person?

This question is often asked but needs some clarification before providing an answer. Radiation cannot be passed from person to person, just as visible light cannot be passed from person to person. However, if you mean radioactive material (which emits radiation) then its possible to pass this between individuals. Radioactive material is a physical substance which may take the form of a solid, liquid or gas. Therefore, if the radioactive material is mobile in the environment then it can be passed from person to person.