Alpha radiation is a type of radiation that consists of particles made up of two protons and two neutrons, which are identical to the nucleus of a helium atom. These particles are emitted during the decay of certain heavy elements, such as uranium and radium. Alpha radiation has low penetration power and can be stopped by a sheet of paper or even the outer layer of human skin. Although alpha particles cannot penetrate deeply into materials, they can be harmful if ingested or inhaled. When alpha-emitting substances enter the body, they can cause significant damage to internal tissues and cells. This makes safety precautions important when handling materials that emit alpha radiation.