15 Mar (NucNet): The Japanese authorities have said the level of radioactivity has been decreasing at the Fukushima-Daiichi nuclear power plant site.
The authorities told the International Atomic Energy Agency (IAEA) that a dose rate of 11.9 millisieverts per hour (mSv/hr) was recorded at midnight UTC (01:00 Central European Time) at the main gate, and at 06:00 UTC (07:00 CET) on 15 March the rate was 0.6 mSv/hour. The IAEA confirmed that earlier, a 400-mSv/hr dose rate was recorded at Fukushima-Daiichi between units 3 and 4. The IAEA said in a statement: This is a high dose-level value, but it is a local value at a single location and at a certain point in time. The agency said it was continuing to confirm the evolution and value of this dose rate.About 150 people from populations around the plant have received monitoring for radiation levels. The results have resulted in measures being taken to decontaminate 23 people. Evacuation of the population from the 20-kilometre zone around the plant is continuing. The Japanese government has asked residents living between 20 km and 30 km of the plant to stay indoors. The authorities have distributed iodine tablets to evacuation centres, but no decision has yet been taken on their administration. The ingestion of stable iodine can help to prevent the accumulation of radioactive iodine in the thyroid. Earlier today there was an explosion at unit 2 of the Fukushima-Daiichi plant and the spent fuel storage pool at unit 4 caught fire with radioactive substances being released directly into the atmosphere after partial destruction of the reactor building. The fire in the storage pool area was probably caused by a hydrogen explosion and has now been extinguished. The Japan Atomic Industrial Forum (JAIF) said damage is suspected to unit 2s inner or primary containment vessel (PCV). Staff and workers, apart from 50 Tokyo Electric Power Company (Tepco) employees involved in the water injection operation trying to cool the plants damaged reactor units 1 to 3, have been evacuated. There was an explosion at unit 3 yesterday and at unit 1 on 12 March, but according to JAIF the PCVs at those units have not been damaged. JAIF has issued an updated status report on all affected units: http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS01_1300189582P.pdf