Originally Posted by 8-Ball
I don't understand.
First, that a meltdown is possible.
Then some users here say that it is NOT possible.
And they will NEVER explode.
But...if the cooling system is down and it is obviously overheating, then there IS possibility of it exploding due to the heat?
And mass radiation in the air is possible either way right?
I think there should be an FAQ on the OP as well, but the OP has done enough work on the updating.
+REP for him by the way.
Meltdowns are possible but improbable. If a meltdown does occur it will likely be a partial meltdown, only affecting a small amount of the nuclear fuel. If this happens it's highly unlikely that the reactor vessel would be breached and everything would be contained within the vessel.
They can explode from excessive pressure. If the heat is great enough and the cooling is inadequate the reactor vessel could rupture. The Japanese however are doing everything they can to ensure adequate cooling(sea water and boric acid injection) and pressure stability(emergency venting).
Mass radiation would require either a massive rupture of the reactor vessel or numerous (were talking weeks to months) of emergency ventilations.
Edit: And time for me to get some sleep. I sleep with the radio on though so if something major happens and I hear it I'll be back.Edited by Lampen - 3/13/11 at 10:29pm