Bruh did you even read about the IFR? It’s 1970s tech a pool sodium reactor has be design a negative Doppler coefficient heating it up automatically due to the base laws of the universe slows the critical reaction rate down.
They pulled the rods out at full power trying to spike it they could not the negative Doppler coefficient kicks in immediately.
Pool cooled sodium reactor are an order of magnitude safer than BWR or PWR for that matter both can melt down a pool sodium reactor simply cannot. It’s thermal mass and secondary guard vessel air cooling by convection keeps the sodium below the boiling point under any conditions.
You can pull the rods AND kill the pumps it will shut down and convention decay heat cool indefinitely.
Literally walk away safe. The humans could be dead and it will just sit there cooling down. Eventually The sodium will freeze and seal it up for good. In a true end of the world scenario. The double top cover and argon cover gas should last thousands if not tens of thousands of years this doesn’t include the impact rated concrete building around all of that.
I can guarantee that they were never even mentioned in Naval nuclear power schools in 1982. I noticed in reading about it tests were conducted by the Department of Energy in 1984. The concept sounds brilliant. The results even better . Thanks for bringing it to my attention!