Here's a report from the ENSI (google translated to English from German):
Accident at Japanese nuclear plant
As a result of the severe earthquake off the Japanese coast on Friday occurred in Japanese nuclear power plant Fukushima-Daiichi to a...n accident involving the release of radioactivity. The Federal nuclear safety inspectorate ENSI has mobilized its emergency organization and analyzes the current situation. For the Swiss population is no danger.
The earthquake in northeastern Japan are three nuclear power plant sites with a total of 13 reactor units affected seriously, Fukushima-Daiichi, Fukushima-Daini and Onagawa. All the reactors were due to the earthquake automatically switched off or they were previously in the review remedy. The size of th damage was caused in Fukushima-Daini, and particularly in Fukushima-Daiichi.
Fukushima-Daiichi
Currently, the blocks are 1 to 3 without AC power supply, there are also the emergency power supply systems failed. It is assumed that the reactor core is damaged in Block 1. The steel shell around the reactor pressure vessel, the so-called containment, was relieved of pressure (venting), ie there was positive pressure filtered vented to the outside. In this block, there was another explosion, which resulted in damage to the reactor building, which includes one-containment. According to Japanese authorities, it was a hydrogen explosion, but the containment itself is still intact. It was currently being flooded with borated sea water to cool the reactor.
About the extent of radioactivity releases continue to be no recent information. According to a release published today gone tomorrow, the radioactivity readings at monitoring stations significantly in the immediate vicinity of the plant. Due to the current weather situation, the radioactivity from spreading into the Pacific Ocean, so currently no large groups of people from the radioactive materials are involved. The authorities, however, the evacuation within a radius of 20 km located around the nuclear power plant and prepare the distribution of iodine tablets.
According to estimates of the likely ENSI outside a radius of 10 km no person by reason of the filtered venting containment receive a radiation dose of more than 1 mSv. This is the same used on the international level for the population.
Units 2 and 3 are currently being cooled with a core isolation cooling system, probably in Block 2, the water level is lower than normal. Blocks 4-6 were before the earthquake in the review remedy, there are no damage reports.
Fukushima-Daini
All four blocks are supplied with AC power from the grid. Units 1 to 4 are cooled. In block 1, but the coolant has drained.
Onagawa
Despite a now deleted fire in a turbine building, all three reactors shut down safely and cooled.
Some more info from the NEOC:
03/13/2011 | 0930 earthquake in Japan
According to official figures from the Japanese authorities was introduced in the reactor, Unit 3 of Fukushima-Daiichi Nuclear Power Station, a pressure relief. In a pressur...e release of radioactive steam is released.
Just yesterday, a pressure relief had been carried out in the reactor block 1. Later the same reactor unit was damaged in an explosion. From block 1, at least small amounts of radioactivity were released.
On the site of the nuclear power plant Onagawa an increased radioactivity measurement was reported. It is currently unclear whether this was caused by the release in nearby Fukushima-Daiichi plant. The Onagawa nuclear power plant was shut down according to authorities details of yesterday as planned. A previously deleted fire involved the engine room, ie a non-nuclear part of the plant.
The protective measures within the Fukushima-Daiichi Nuclear Power Plants (evacuation within 20 km) and Fukushima-Daini (evacuation within 10 miles) remain in force.
The weather conditions have not to date significantly altered. Released radioactivity was still driven eastward across the Pacific.
The NAC continues to monitor the situation and will be constantly informed.
Accident at Japanese nuclear plant
As a result of the severe earthquake off the Japanese coast on Friday occurred in Japanese nuclear power plant Fukushima-Daiichi to a...n accident involving the release of radioactivity. The Federal nuclear safety inspectorate ENSI has mobilized its emergency organization and analyzes the current situation. For the Swiss population is no danger.
The earthquake in northeastern Japan are three nuclear power plant sites with a total of 13 reactor units affected seriously, Fukushima-Daiichi, Fukushima-Daini and Onagawa. All the reactors were due to the earthquake automatically switched off or they were previously in the review remedy. The size of th damage was caused in Fukushima-Daini, and particularly in Fukushima-Daiichi.
Fukushima-Daiichi
Currently, the blocks are 1 to 3 without AC power supply, there are also the emergency power supply systems failed. It is assumed that the reactor core is damaged in Block 1. The steel shell around the reactor pressure vessel, the so-called containment, was relieved of pressure (venting), ie there was positive pressure filtered vented to the outside. In this block, there was another explosion, which resulted in damage to the reactor building, which includes one-containment. According to Japanese authorities, it was a hydrogen explosion, but the containment itself is still intact. It was currently being flooded with borated sea water to cool the reactor.
About the extent of radioactivity releases continue to be no recent information. According to a release published today gone tomorrow, the radioactivity readings at monitoring stations significantly in the immediate vicinity of the plant. Due to the current weather situation, the radioactivity from spreading into the Pacific Ocean, so currently no large groups of people from the radioactive materials are involved. The authorities, however, the evacuation within a radius of 20 km located around the nuclear power plant and prepare the distribution of iodine tablets.
According to estimates of the likely ENSI outside a radius of 10 km no person by reason of the filtered venting containment receive a radiation dose of more than 1 mSv. This is the same used on the international level for the population.
Units 2 and 3 are currently being cooled with a core isolation cooling system, probably in Block 2, the water level is lower than normal. Blocks 4-6 were before the earthquake in the review remedy, there are no damage reports.
Fukushima-Daini
All four blocks are supplied with AC power from the grid. Units 1 to 4 are cooled. In block 1, but the coolant has drained.
Onagawa
Despite a now deleted fire in a turbine building, all three reactors shut down safely and cooled.
Some more info from the NEOC:
03/13/2011 | 0930 earthquake in Japan
According to official figures from the Japanese authorities was introduced in the reactor, Unit 3 of Fukushima-Daiichi Nuclear Power Station, a pressure relief. In a pressur...e release of radioactive steam is released.
Just yesterday, a pressure relief had been carried out in the reactor block 1. Later the same reactor unit was damaged in an explosion. From block 1, at least small amounts of radioactivity were released.
On the site of the nuclear power plant Onagawa an increased radioactivity measurement was reported. It is currently unclear whether this was caused by the release in nearby Fukushima-Daiichi plant. The Onagawa nuclear power plant was shut down according to authorities details of yesterday as planned. A previously deleted fire involved the engine room, ie a non-nuclear part of the plant.
The protective measures within the Fukushima-Daiichi Nuclear Power Plants (evacuation within 20 km) and Fukushima-Daini (evacuation within 10 miles) remain in force.
The weather conditions have not to date significantly altered. Released radioactivity was still driven eastward across the Pacific.
The NAC continues to monitor the situation and will be constantly informed.
