NY TIMES: "Japan’s nuclear crisis verged toward catastrophe on Tuesday after an explosion damaged the vessel containing the nuclear core at one reactor and a fire at another spewed large amounts of radioactive material into the air, according to statements from Japanese government and industry officials." »
And the Times relays this extraordinary act of selflessness:
Engineers at the plant, working at tremendous personal risk, on Tuesday continued efforts to cool down the most heavily damaged unit, reactor No. 2, by pumping in seawater. According to government statements, most of the 800 workers at the plant had been withdrawn, leaving 50 or so workers in a desperate effort to keep the cores of three stricken reactors cooled with seawater pumped by firefighting equipment, while crews battled to put out the fire at the No. 4 reactor, which they claimed to have done just after noon on Tuesday.
…Radiation measurements reported on Tuesday showed a spike of radioactivity around the plant that made the leakage significantly worse than it had been, with levels measured at one point as high as 400 millisieverts an hour. Even 7 minutes of exposure at that level will reach the maximum annual dose that a worker at an American nuclear plant is allowed. And exposure for 75 minutes would likely lead to acute radiation sickness.