Source from UC Berkeley Nuclear Engineering Air Monitoring Station
カリフォルニア大学バークレー校の検査結果
Seaweed Sample
海藻
source: coastal areas of Northern California
北カリフォルニア海岸にて採取
Collection Time (採取日): 5/24/2012
Species (種類): Nori のり
Sample Mass (サンプル量): 80 g
Counting Time (測定時間): 954,450 sec.
Energy Resolution: 2 keV (at 1461 keV)
Cs 134 Less Than MDA (0.10 bq/kg)
Cs 137 Less Than MDA (0.16 bq/kg)
セシウム検出限界(MDA)以下
2011年4月からの全ての検査結果は以下のとおり。
All the results for
seaweed testing from Northern California are shown below.
Collection Date
|
Sample Mass
|
Species
|
I131
|
Cs134
|
Cs137
|
04/19/2011
|
0.55 kg(wet)
|
Porphyra
あまのり
|
< MDA
[0.15bq/kg]
|
< MDA
[0.30bq/kg]
|
< MDA [MDA=0.28kg]
|
05/18/2011
|
1.87kg (wet)
|
Porphyra
あまのり
|
< MDA [0.17bq/kg]
|
< MDA [0.11bq/kg]
|
< MDA [0.09bq/kg]
|
05/04/2011
|
0.50kg(dry)
|
Wakame
わかめ
|
< MDA [0.57 bq/kg]
|
< MDA [0.41 bq/kg]
|
< MDA [0.41 bq/kg]
|
05/05/2011
|
0.11kg (dry)
|
Nori
のり
|
< MDA [1400 bq/kg]
|
< MDA [0.62 bq/kg]
|
< MDA [0.62 bq/kg]
|
05/05/2011
|
0.14kg (dry)
|
Kombu
こんぶ
|
< MDA [2800 bq/kg]
|
< MDA [1.33 bq/kg]
|
< MDA [1.11 bq/kg]
|
06/01/2011
|
0.15kg (dry)
|
Kombu
こんぶ
|
< MDA [230 bq/kg]
|
< MDA [0.92 bq/kg]
|
< MDA [0.79 bq/kg]
|
06/08/2012
|
0.36kg (dry)
|
Wakame
わかめ
|
< MDA [0.70 bq/kg]
|
< MDA [0.12 bq/kg]
|
< MDA [0.15 bq/kg]
|
05/21/2012
|
0.34kg (dry)
|
Kombu
こんぶ
|
< MDA [57 bq/kg]
|
< MDA [0.10 bq/kg]
|
< MDA [0.16 bq/kg]
|
05/24/2012
|
0.08kg (dry)
|
Nori
のり
|
< MDA [660 bq/kg]
|
< MDA [0.30 bq/kg]
|
< MDA [0.33 bq/kg]
|
MDA stands for Minimum Detectable Activity
いくつかのサンプルの検出限界が他に比べてあまりにも高いのが気になります。
I 131 MDA of some samples are very high.
How we calculate MDA
どなたか、説明できる方いらっしゃいますか?
Could someone explain what it means?