Kontrollradad

Kontrollradad is a term that appears in some Swedish-language technical writing to describe the state or condition of a nuclear reactor when control rods are inserted into the reactor core to regulate or halt fission reactions. The word is formed from kontroll (control) and rad (a root associated with rod) with the suffix -ad to indicate a state or condition. In usage, kontrollradad can function as an attributive or predicative description, for example to characterize a reactor configuration where control rods have been moved into position.

In the context of nuclear reactors, control rods are made from neutron-absorbing materials such as boron, hafnium, or cadmium. Their primary purpose is to adjust reactivity by absorbing neutrons; inserting the rods reduces neutron flux and moves the core toward subcritical or a safe shutdown state, while withdrawing rods increases reactivity. The term kontrollradad emphasizes the presence and effect of the rods in achieving a controlled, moderated, or halted reaction.

Beyond its lexical use, the concept aligns with standard safety and operational ideas in reactor engineering: control rod worth, shutdown margins, and reliable actuation are essential for preventing unintended power excursions. The term is not as common as the more general kontrollstav or kontrollrods in standard Swedish references, but it is encountered in some discussions of reactor control configurations.

See also: Control rod, Nuclear reactor, Reactor shutdown, Reactivity control.