This is the basis for nuclear power production. The radiation produced from radioactive atoms is emitted in several forms, most commonly, alpha and beta particles, and gamma rays. Alpha particles have the shortest range among these three types of radiation. They can travel only a few inches in the air and can be stopped easily by a sheet of paper or the outer layer of a person s skin. Alpha particles are harmful only if the radioactive source material is swallowed, inhaled, or absorbed into a wound.
Beta particles are more penetrating than alpha particles.
They can travel through the air for several feet, but their penetrating power, too, is limited. Although they can pass through a sheet of paper, materials such as a thin sheet of aluminum foil or glass can stop them. Like alpha particles, they cause their most serious effects if swallowed or inhaled. Some radioactive material that emits beta particles could, for example, be attached to dust we might breathe in, or cling to food we might eat. In such cases, some of the material would leave the body through natural elimination processes.