Osaka (Japan): Japan`s nuclear safety
agency on Friday raised the Fukushima crisis level to five from
four on the international scale of gravity for atomic
accidents, which goes to as high as seven.
The decision by the Nuclear and Industrial Safety
Agency (NISA) puts Fukushima on the same level as the 1979
accident at Three Mile Island in Pennsylvania and makes it the
worst ever in Japan.
A spokesman for the agency said it had alerted the
IAEA on its decision, which was made due to the condition of
reactors one, two and three at the plant stricken by last
week`s massive earthquake and tsunami that devastated swathes
of northeastern Japan.
"The cooling function was lost and the reactor cores
were damaged. Radioactive particles continue to be released in
the environment," he said.
Among the six reactors at the power plant, reactors
one, two and three were operating at the time of the magnitude
9.0 quake and halted automatically.
But the cores are believed to have partially melted
because the twin disasters knocked out the plant`s reactor
cooling systems, sparking a series of explosions and fires.
Authorities have since struggled to keep fuel rods
inside reactors and fuel storage containment pools under
water. If they are exposed to air, they could degrade further
and emit large amounts of dangerous radioactive material.
France`s Nuclear Safety Authority rates the Fukushima
crisis at six on the scale. The Chernobyl disaster is put at
seven, the highest.
Level 3 indicates a "serious incident" according to
the International Atomic Energy Agency (IAEA) scale, while
level four means there has been an "accident with local
The March 28, 1979 accident at Three Mile Island was a
partial reactor meltdown that led to "very small" releases of
radioactivity, according to the US Nuclear Regulatory
It caused no casualties, but was rated five on the
scale, corresponding to "an accident with wider consequences."
Level 6 is a "serious accident".
The April 26, 1986 explosion at the Soviet nuclear
power plant in Chernobyl -- rated a maximum 7 -- was the
world`s worst nuclear disaster.
Unleashed by an unauthorised technical experiment, it
spewed radioactive dust over swathes of Ukraine, Belarus,
Russia and western Europe. Estimates of the death toll range
from a UN 2005 figure of 4,000 to tens or even hundreds of
thousands, proposed by non-governmental groups.