Nuclear radiation is the release of energy-bearing rays, waves or particles that occurs when an atom is split. This specific process is called fission, and it can occur in both natural and artificial situations. Nuclear energy can be harnessed from these reactions and transformed into usable electricity, but the waves and particles released during fission can also cause radiation that is dangerous to living beings.
During fission, a nucleus splits into multiple nuclei and often several byproducts, such as alpha and beta particles, gamma rays and free-floating neutrons. These byproducts have differing levels of energy and can be used in a variety of ways, such as to power devices like smoke detectors (which utilize alpha rays) or x-ray machines. Because alpha and beta particles have the lowest energy level, their path can be blocked by something as insubstantial as a sheet of plastic or a block of wood. Gamma rays and x-rays have a much higher energy, and only a dense material like lead can block them. Neutrons are the most unstable of all particles and have the ability to cause an object to become radioactive. When they penetrate an object, they break down chemical bonds and thus change the molecular structure of that object. In humans, animals and plants, this can create serious health complications.