Molten Salt Reactors are incapable of having “Loss of Coolant Accidents”. The molten fuel and coolant are chemically bound, and they remain liquid (not becoming a gas, even at temperatures much higher than the reactor operating temperature).
Our current Light Water Reactor (LWR) technology is limited by steam’s low heat transfer capacity, and the pressure needed to keep very hot water a liquid; most of the expense of LWR is high-pressure pipes, safety systems to prevent pressure explosions or loss of coolant when pipes break, and the huge steam containment building, which are obviously all for containing high-pressure 350ºC water.
(At Fukushima, the reactors were shut down properly before the tsunami struck. Fukushima reactor core damage, hydrogen buildup, and radiation leakage was from loss of water coolant, after losing power to the cooling systems. That type of accident simply can’t happen in a molten fueled, salt cooled reactor.)
LFTRs and all other MSR, have no water in the reactor. In all types of Molten Salt Reactor, the fuel is dissolved in molten salt and transfers heat (via heat transfer units without any radioactive materials) out of the reactor. The fuel salt remains liquid (not becoming a gas), even at temperatures much higher than the reactor can ever get, and so everything in the reactor remains at atmospheric pressure.
LFTRs can be installed even in deserts. LFTRs can be located in small sites wherever needed, or even transported for military uses or disaster relief. Use reactor heat for generating electricity and other industrial processes, such as desalinating water or making gasoline from carbon dioxide and water.
Transfer any unused heat to air or water, or even keep it in the reactor; the reactor can’t get hot enough to melt any reactor materials. Molten Salt Reactors are extremely stable, since any increase in fuel temperature expands the molten fuel, slowing the fission rate, quickly and automatically.
If water somehow got in the reactor (e.g. a tsunami or hurricane), it would simply boil away. (Also, most plans for MSR installations are several meters underground, protecting the reactor from weather or external events.) Nothing in any type of Molten Salt Reactor chemically reacts with water or dissolves in water, and all transuranic elements are strongly chemically bound to the fluoride salts.
If there was structural damage, passive safety systems would simply dump the fuel into passive cooling tanks. (Later re-heat and the pump fuel back into the reactor.)