Explaining Japanese Nuclear Explosion

On the video below the scientist gives a plausible explanation for reactor number 3 actually blowing up from a small nuclear explosion of the fuel rods. He says the governments can say for sure right now if his theory is correct by analyzing the air sample data he knows they have gathered.

The bad news is it does appear the probable nuclear explosion has pulverized bad stuff like uranium into a fine enough power that it has been found as far away as New England. You breath it or consume it - you're dead in a decade or so. But by then that will be your problem won't it?

Gundersen Postulates Unit 3 Explosion May Have Been Prompt Criticality in Fuel Pool from Fairewinds Associates on Vimeo.