Energy moving in the form of particles or waves. Familiar radiations are heat, light, radio waves, and microwaves. Ionizing radiation is a very high-energy form of electromagnetic radiation.

KI (potassium iodide) is a salt of stable (not radioactive) iodine that can help block radioactive iodine from being absorbed by the thyroid gland, thus protecting this gland from radiation injury.

Reactor: Those components which, together, support the controlled fission process and the generation of steam for the purpose of producing power. Components include the reactor core, reactor vessel, control rods and reactor coolant system. Fuel Cladding: The long zirconium metal tubes in which the fuel pellets are stacked. The fuel cladding along with the fuel pellets are referred to as 'fuel rods.' The fuel cladding serves as the first and primary fission product barrier. Fuel Assembly: An array of fuel rods (plus guide thimbles and an instrument tube) held together by grid assemblies.

The heat energy produced by the process of nuclear fission within a nuclear reactor or by radioactive decay.

The plant and its equipment are designed to withstand most natural events (earthquakes, floods, high winds, tornados, etc.). Plant operators monitor these events to ensure they do not threaten safe operation of the plant. If events occur that may threaten safety, operators take action to place the plant in a safe condition. If it has been determined that an event such as an earthquake, tornado, flood, etc. has occurred, plant shutdown may be required. Operators will perform a normal plant shutdown and engineering evaluations will be performed.

Irradiated Fuel: A fuel assembly which has been involved in the fission process and is no longer effectively producing energy, but is still radioactive. Also known as "spent fuel". Refueling: The reactor is shutdown with reactor coolant temperature below 210° F and the reactor coolant system is open (reactor vessel head removed) to allow for irradiated fuel to be removed and new fuel assemblies to be added.

Any place where the level of radioactive contamination is considerably greater than the area around it.

The specific events or symptoms that would signal to station personnel that an emergency is taking place are called Emergency Action Levels (EALs). Once a particular EAL has been reached, the Emergency Plan and related procedures specify what kinds of responses are necessary. The level of this response is based on how seriously the condition threatens plant and public safety, so it is called a graded response. Unusual Event: A low level event which poses no threat to public safety but which warrant an increased awareness on the part of plant and off-site agency personnel.

In reference to the reactor, a self-sustaining nuclear chain reaction that releases energy. During normal plant operations the reactor is 'critical'.

The central location from which the plant is operated, monitored and controlled. The control room is equipped with the instrumentation and alarms necessary to continually assess the status of the reactor plant. The control room is continuously manned.