Nuclear and process safety - Part 2

For those of who saw the videos of the explosion in the nuclear reactor in Japan, you must have observed the blast wave destroying the wall panels but the metal structure stayed intact. I believe the design worked as intended. But the news that sea water is being used for cooling indicates the seriousness of the situation. In a chemical plant emergency, we do not have to deal with radiation leaks but imagine the plight of the emergency responders in the Japan nuclear plant. They must wear protective clothing for the radiation and tackle the emergency also. For those of you who want to know a little more about the nuclear reactor incident, see this link
Another good article is in this link.
Read an explanation about the second reactor explosion in this link.