Tuesday, March 22, 2011

JAPAN - The myth of nuclear security has exploded

At the Chernobyl nuclear disaster in 1986, the severity level was 7 on the International Nuclear Event Scale (INES), which is the highest level. The Agency's Nuclear Safety Department of Economy and Industry estimates that the accident at the Fukushima Daiichi Tepco is level 6. Dozens of villagers near the plant have been irradiated.

In the present state of things, radioactive particles are in contact only with the clothes of the inhabitants. It is feared that the number of irradiated increases again, so it must quickly find a solution. At the edge of the enclosure of the nuclear plant, was measured in the morning of March 13 204.2 microsieverts radioactivity per hour (natural radiation to which a person is subjected on a daily basis does not exceed 0.27 mSv / hr) .

This contamination results from the successive incidents that occurred in reactor No. 1, and in No. 3. When the water level drop inside the reactor, the fuel rods are exposed to air, the temperature rises and materials based. At the risk of condemning the reactor, TEPCO decided to inject sea water into the reactor vessel to prevent the disaster.

But the operator could not he make this decision earlier? For this kind of decision, it requires both the expertise of the nuclear safety agency, but a government policy decision. The safety of residents must be the priority. One may wonder if there has been a bad risk assessment in setting safety standards.

The magnitude of the earthquake which shook eastern Japan, initially 8.8, was reassessed at 9. Chile and Indonesia have experienced in the past earthquakes of this magnitude. And, as a country seismic, Japan would have had to build its power by considering all possibilities. The plant no longer receiving power from the outside, generators running on diesel fuel should have taken over.

However, these backup generators were inoperable. If the emergency cooling system, called ECCS (Emergency Core Cooling System), could not work, because there was no electricity. This accident shows how Japan is dependent on nuclear power. Fifty-four reactors are in operation in Japan, providing about 50 million kilowatts.

Japan is the largest nuclear power after the United States and France, while being one of the most seismic of the world. We used to speak of the "myth of nuclear safety." Despite the accidents at Three Mile Island and Chernobyl, Japan, confident in its security measures and the type of reactor used, has never challenged this myth.

However, the situation in Fukushima teaches us that technology and science are not a panacea and that they contain serious flaws. Today, daily life as the industry can not do without nuclear energy. It is an indispensable energy source at a time when we fight against global warming. But it will no longer be possible to live near power plants as they are today.

Population will live in peace if improvements are not made to the technologies and control procedures. The priority now is to rehabilitate the affected areas, but we have much to learn: how to improve the safety of plants currently in operation, what would he have been made to ensure the safety of people and gain their trust ? We'll have to check these points one by one.

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