The sirens may also be used to warn area residents of tornadoes and other natural disasters. Radiation is energy emitted as invisible particles, waves, or rays. Radioactive atoms produce radiation as they disintegrate. Everyone is exposed to small amounts of radiation each day. Air, water, food, and sunshine are a few sources of natural background radiation.
Radiation also comes from other sources, such as color televisions and medical x-rays.
People are concerned about radiation exposure because it can alter or damage the human cell structure. That is why nuclear power plants are carefully monitored and employees are trained to limit their exposure to a level that is as low as reasonably achievable. The containment building, the reactor vessel, the fuel assemblies, and several other barriers are designed to contain radiation and protect plant workers and the public living near a nuclear plant from any exposure to elevated levels of radiation. Repeated surveys around TVA's operating nuclear plants have shown no detectable increase in radiation levels over normal background levels.