Table 4.
Contribution of Element Groups to Fission Product Activity
Time after test:
Percent Contribution
25d
lyr.
10 yrs.
20 yrs.
Rare earths*
50
63
42
30
Alkaline earths
17
5.7
39
46
Noble metals
10.6
5.7
0
0
Nb, Zr*
10.0
0
0
Element Group
23
Rare gases**
5.3
0.4
2.7
2.0
Halogens**
4.8
0
0
0
Oxygenated anions
1.6
0
0)
0
17
21
Alkali metals
v0
1.5
*Refractory
**Not condensable
564