Fission products generated during nuclear reactions that have high neutron absorption, removing neutrons from the reactor and possibly causing the chain reaction to stop.

Made of chemical elements that can absorb many neutrons and control the rate of fission in a reactor core.

These are produced through a chain of beta and gamma decay in the reactor.

This type of reactor has three independent loops, preventing any leakage of radioactive isotopes from the reactor core.

Levels of safety protection in the reactor, from the fuel rods to the containment building.

In this type of reactor, the radioactive loop (reactor core) is not independent, potentially allowing radioactivity to enter the turbines.

The outer layer of the fuel rods, with low absorption cross section for thermal neutrons, prevents radioactive fission fragments from escaping the fuel into the coolant and contaminating it.

With this part of an NPP, a small fraction of the cooling water evaporates and escapes as a vapor plume.

This part of the NPP is pressurized and and self-contained, and contains the reactor coolant and reactor core (with fuel assemblies)..