Ah, I should have said "an explosion inside one of the buildings," that would have been clearer. But yeah, I'd been getting most of my info from the media, which is probably not the best source in this type of situation, as Drew illustrated so well when he provided the link to the bravenewclimate March 16th summary in the news thread early this morning. :)
The Wikipedia link I provided in the news about containment systems does mention though that although gas venting is an intentional part of the upgrade to the Mark I containment systems, it's *supposed* to go through a scrubbing process that greatly reduces the radioactivity of the released gas--so it sounds like something there might not have gone quite as well as intended.
At least I didn't buy into the multiple press reports I saw saying the containment system had actually been breached. >_<
I was *wondering* why "Richter" wasn't mentioned in the articles I was seeing! (So to be fair to the reporters, that was my error, not theirs.) None of the reporters seemed to bother to mention the moment magnitude scale, so thank you very much for mentioning it! I'll miss that name though, it just sounds nice.
Ooh, that MIT second page is a nice one for silly people like me. Thanks for all the info. :)