THE 'JAPANESE' CLOUD OVER POLAND
(polish ver.)
On Friday, the 11th of March 2011, an earthquake of force 9 on the Richter scale occurred in the Japanese power station Fukushima I (Fukushima Dai-ichi), equipped with 6 Boiling Water Reactors (BWR).
Approximately on Wednesday (the 23rd of March 2011) the first cloud of the air from the Fukushima power plant reached Poland. It seams that it contained small quantities of fission products (mainly radioactive iodine I-131). Because of the distance from the damaged nuclear power plant to our country boarders (about 8500 km), radionuclides found in the ground-level air over our country, are
'dilluted'.
Since the air clouds from power plant Fukushima appeared over Poland, concentrations of artificial isotopes in the atmosphere were steadily growing (from one measurement to another increasing value was registered). Measurements from Friday (the
1st of April 2011) showed a breakthrough. That day, for the first time, we registered a lower concentration of radioactive iodine I-131 over Poland in relation to measurements made two days earlier. Since that
time (the 1st of April 2011), concentration of this radioisotope in the air masses over the territory of Poland are systematically declining, from measurement to measurement, and are now at the level below 400 microbecquerel per cubic meter of air. These are very low concentrations.
For comparison, we would remain that during the clouds movement over the territory of our country after the accident of the Chernobyl nuclear power plant, the recorded concentrations of iodine I-131 were reached of 200 Bq/m3 (becquerel per cubic meter of air). At present, the recorded concentrations are tens of thousands times lower and do not affect, in any way, the Polish people or the environment of our country.
Below, you will find a document showing the concentration of iodine I-131 and other radioactive isotopes that are present in the air at several locations in Poland. These are data from a network of highsensitive air monitoring stations
type ASS-500*, working in the network of early warning radioactive contaminations of the President of
NAEA (the nominal air flow through the filter station is 500 m3/h). The data are continuously added to the document, which contains the results from the first air masses which arrived in Poland from Fukushima NPP. The new results
are added from the centers, which measure the filters immediately after removing from the station
ASS-500. Unfortunatelly, several centers in the country do not have the highsensitive spectrometry devices, therefore the filters of these stations will be measured successively (as soon as possible) at the Central Laboratory for Radiological Protection in Warsaw and the results of these stations may appear in a file with some delay.
* Patent, the production of the air
monitoring stations type ASS-500 and the supervision of the network operation - Central Laboratory for Radiological Protection
