Methodology

■    The depth of collection is from 0 to 5 cm, because most of cesium stays within 5 cm from surface of the earth.

Collection of soil should be conducted when it does not rain for several days, in order to avoid weight error 
caused by water. Less than 10 percent of moisture content is desirable.

■ Spot for collection is set at higher dose spot by measuring rate of air dose (1m、5cm). 
　The extreme high spot such as micro hot spots and concentrated environment are excluded.

■ Collection is made by a standardized method to compare results of each place.

■ Samples are measured at the participating laboratories of MDS.

　　・Measurement accuracy of those laboratories is ensured by the MDS original examination.   

　　・The result is accumulated in the common database.  

■ The result of measurement is open to public on MDS. MDS has Japanese and English site.

■ Mapping of data is planned after gathering enough results.

■ Trial calculation of amount of radioactivity by a square meter is planned to be conducted. (Becquerel/ Kg →Becquerel /square meter)