In accordance with the definition of the German Atomic Energy Act, nuclear fuel consists of special fissile substances in the form of

  • plutonium-239 and plutonium-241,
  • with the isotopes 235 or 233 enriched uranium,
  • substances containing one or several of the aforementioned substances,
  • substances with the aid of which a self-perpetuating chain reaction can be upheld in a suitable plant (reactor) and which are determined in an ordinance having the force of law.