Everyone is talking about zirconium. I recently found this

What's Behind the Two Fukushima Explosions? Does Zirconium Explode at 2,000 Degrees? | techyum ::

So...what's really behind the two Fukushima explosions? Were they hydrogen, or something else? You tell me, Dr. Fabulous. But here's what I know, and here's how an anti-nuclear activist just pissed me off by setting off my bullshit detector.

CommonDreams.org has a piece by Karl Grossman, journalism professor, anti-nuke activist and author of the 1980 book Cover Up: What You Are Not Supposed to Know About Nuclear Power, that is getting a lot of play in the wake of a second hydrogen explosion at the Fukushima I plant. It appears to have been written before the second explosion.

In this article, Grossman makes some claims about the element zirconium, used in the fuel cladding around the nuclear fuel, that set off my bullshit detector for no good reason. I don't, or didn't, know squat about zirconium or zircaloy. But his arguments sounded strange.

Behind the Hydrogen Explosion at the Fukushima Nuclear Plant | Common Dreams

Eruption of hydrogen gas as a first reaction in a loss-of-coolant accident has been discussed with great worry in U.S. government and nuclear industry literature for decades.

That is because a highly volatile substance called zirconium was chosen back in the 1940's and 50's, when plans were first developed to build nuclear power plants, as the material to be used to make the rods into which radioactive fuel would be loaded.

There are 30,000 to 40,000 rods--composed of twenty tons of zirconium--in an average nuclear power plant. Many other substances were tried, particularly stainless steel, but only zirconium worked well. That's because zirconium, it was found, allows neutrons from the fuel pellets in the rods to pass freely between the rods and thus a nuclear chain reaction to be sustained.

So, in what may be my last act of "advising", I'll advise you to cut the jargon. -- My old PhD advisor, to me, 26/2/11