 One of the most common nuclear concerns, other than the fear of nuclear weapons, is the fear of nuclear radiation, mostly because of the fact that radiation can be dangerous at high doses, while still being impossible to see or feel. Almost everyone will have heard about the concept of radiation sickness, but very few people understand the pervasiveness of radiation and how you are constantly exposed to radiation from both natural and artificial sources. We have already looked at the three main types of nuclear radiation. Alpha and beta radiation both take the form of energetic charged particles, while gamma rays are photons of electromagnetic radiation. All three forms of radiation interact via the electromagnetic force, which means they will interact with charged particles. Now imagine a beam of radiation incident on some form of material, which is of course made of atoms, each consisting of a tiny nucleus and a much larger cloud of electrons. The relative size of the nucleus versus the size of the electron cloud means that the incident radiation will almost certainly interact predominantly with the electrons. Now consider the relevant energy scales. Typical nuclear radiation is of the order of an MEV in energy, whereas the energy required to remove an electron from the atom is around 10EV. The consequence of this huge difference in energy scale is that when the energy of the radiation is transferred to the electrons in materials, the electrons are knocked completely out of the atoms, leaving behind a trail of free electrons and ionized atoms. Higher energy radiation creates greater amounts of ionization, and the radiation dose is quantified by the amount of energy deposited, or equivalently, the amount of ionization created.