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Glossary S - T
SRadTown Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | xyzSite
Any installation, facility, or discrete, physically separate parcel of land, or any building or structure or portion thereof, that is being considered for survey and investigation.
Source or Sealed Source
Small, sealed metal cases containing radioactive materials used as references in research and industrial processes. They are often part of specialized industrial devices that measure quantities as the moisture content of soil or the density or thickness of materials. The sources are usually enclosed in a housing that prevents the escape of the radiation. Often referred to as radioactive sources or sealed sources.
Spent Nuclear Fuel
Nuclear reactor fuel that has been used to the extent to that it can no longer effectively sustain a chain reaction
Stable Nucleus
A nucleus in which the forces among its particles are balanced. See unstable nucleus as well.
RadTown Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | xyzTerrestrial Radiation
Radiation that is emitted by naturally occurring radioactive materials, such as uranium, thorium, and radon in the earth. (see also naturally occurring radioactive materials)
Thorium
A naturally occurring radioactive metal found at very low levels in soil, rocks, water, plants and animals. The most common naturally occurring forms of thorium are thorium-232, thorium-230 or thorium-228.
Transuranic
Elements with atomic numbers higher than uranium (92). For example, plutonium and americium are transuranics.
Tritium
Tritium (chemical symbol H-3) is a radioactive isotope of the element hydrogen (chemical symbol H).