| A | B |
| Primary systems | Systems that convert fission energy to steam |
| Secondary systems | Systems that convert steam energy to electricity |
| Control systems | Monitor & control plant parameters |
| Function of nuclear power plant | Produce electricity for consumers from nuclear fission energy |
| Reactor coolant system | Transfer heat from reactor to steam generators |
| Chemical & volume control system | Maintains reactor coolant volume & chemistry |
| Residual heat removal system | Remove decay heat |
| Main steam system | Contain & transport steam from steam generator to turbine |
| Emergency Core Cooling System | Cool reactor core & keep reactor shut down during emergencies |