If there is no danger of a nuclear power plant having a nuclear explosion(if the reaction got out of control),?

why do we need to build containment buildings for the core?If there is no danger of a nuclear power plant having a nuclear explosion(if the reaction got out of control),?
Clearly, there must be a way to separate the reactor core and its radiation from the environment. That is the job of the containment building. It must contain any radioactive material -- uranium or water -- that might get to the environment.





While there is no danger of a nuclear detonation, there is a danger of a steam explosion, just as there could have been at Three Mile Island. But the real reason why containment buildings are so strong is not a danger from the inside, but from the outside. They have to be strong enough to withstand an airplane crash, or a terrorist bomb, among other things.





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The Canadian CANDU reactors do NOT use tritium in any way. There is only a very small amount of naturally occurring tritium in the world. The Canadian reactors use heavy water as their moderator, rather than light water (normal water) as in the US. The heavy water is D2O, deuterium oxide, and is very expensive. The CANDU reactors usually use un-enriched uranium because they have no facilities for enriching uranium. Natural uranium does not reach a critical mass and cause a chain reaction. The Canadian reactors would be impossible were it not for the heavy water. The heavy water causes more neutrons to move more slowly and allow a chain reaction to occur where it wouldn't in nature.





A loss of the heavy water will cause an automatic shutdown of the reactor, since the D2O is what allows there to be a chain reaction, but residual heat can cause substantial damage to the ';innards'; of a CANDU reactor.





There are small amounts of tritium produced and released during the operation of a CANDU reactor. This tritium is considered an environmental hazard.If there is no danger of a nuclear power plant having a nuclear explosion(if the reaction got out of control),?
American power plants can have a meltdown due to using enriched uranium fuel supplied by Canada, however the Canadian power plants cannot have a meltdown cause they use lower percentage uranium rods, simply drain the tritium water and the reaction stops. American power plants that doesnt work and you end up with 3 Mile Island.
There can still be a conventional explosion (involving regular fires and regular steam) even if there isn't a nuclear one.
Google nuclear melt down