In a second the reactor coolant began to boil.
Atomics International decided sodium was a more appropriate nuclear reactor coolant than water.
Then, I want to drain the reactor coolant and make sure the flow of additional coolant is shut down.
If it ever became necessary to drain off the reactor coolant, the tunnels would handle that, too.
As the pressure in the primary system continued to decrease, reactor coolant continued to flow, but it was boiling inside the core.
As the system pressure decreased further, steam pockets began to form in the reactor coolant.
Leakage from the so-called "reactor coolant pressure boundary" is required to be monitored in nuclear power plants.
The reason was obvious: the smallest leak of reactor coolant had to be instantly visible even if all the detectors failed.
The reactor coolant, which carried short-lived but dangerous radioactivity, never flashed to steam.
Lithium-7 gained interest for use in nuclear reactor coolants.