Shielding - Panasonic PT-DZ12000U Operating Instructions Manual

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mixed /
â ã
neutron
as polyethylene) then neutron absorber (such as Cd,
B, Li, Hf), then high Z to absorb "capture gammas"
MeV 0.10
U 0.005
W 0.008
Pb 0.012
Sn 0.06
Cu 0.18
Fe 0.25
Al 1.12
Concrete 1.8
Water 4.20
This table applies to a thin shield and no provision is made for
buildup factor. Always perform a radiation measurement to
confirm adequacy of shield.
Simply multiply the half-value thickness by the square root of
10 (3.162) to get the tenth-value thickness.
Example: A half-value thickness of concrete for Cs-137
gamma radiation is 3.8 cm.
The tenth-value thickness is 3.8 cm x 3.162 = 12 cm.
SHIELDING MATERIALS
N/A
low Z, such as plastic or aluminum
high Z, such as tungsten
low Z, then high Z
hydrogenous material to thermalize (such
Photon Half-Value Layers in CM
0.60
0.25
0.35
0.52
1.20
1.01
1.15
3.30
3.8
7.80
Tenth-value Thickness
1.00 2.00
0.48 0.78
0.58 0.82
0.90 1.35
1.38 1.80
1.70 1.65
1.32 1.55
4.45 5.90
4.6 6.2
9.60 14.2
53
6.00 15.00
0.80 0.62
0.85 0.67
1.39 1.08
2.65 2.20
2.49 2.38
2.88 2.85
9.67 11.7
11.2 10.4
25.0 35.7