Physicists feared second explosion would create radioactive cloud as residents panicked, jamming city’s exit roads
London Guardian 
Saturday, March 12, 2011
For a few unnerving hours, Japan faced a bleak and unsettling prospect. The devastation wreaked by Friday’s earthquake and tsunami seemed set to be followed by a nuclear meltdown that could have spread radioactive waste over large parts of the country.
The nation was one short step away from enduring genpatsu-shinsai – an atomic disaster triggered by earthquake that leading Japanese seismologists had been predicting for several years.
Fears of nuclear mayhem were raised when a massive explosion rocked the Fukushima Daiichi atomic power plant following damage to one of its reactors in Friday’s earthquake. A pall of grey-white smoke rose over the plant, operated by Tokyo Electric Power, and it was reported that four workers had been injured.
Government officials revealed plans to distribute iodine tablets – a treatment for radiation poisoning – to locals while a 20km exclusion zone were set up round the plant. Residents outside the zone were urged to stay inside, close doors and windows and turn off air conditioning. Scientists had detected eight times the normal radiation levels outside the facility and 1,000 times normal levels inside the affected unit’s control room.
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