Example of Bomb-Pit Construction: 1 Meter Diameter
Example of Bomb-Pit Construction: 1 Meter Diameter
Example of Bomb-Pit Construction: 1 Meter Diameter
I3
Steel Closure
C I6 I1 C
I4 0.5 meter I6 0.5 meter I4
o o
n n
c c
r r
e e
t t
e e
w w
a a
Depth = 1.5 meter l l
l l
Depth = 1.5 meter
Ground
I0 Ground
I2 I2
I5 I5
1 meter diameter
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Prepared by : MOHD HUZAIRI RUSLI @ 24/01/2018
Maximum dose rate on external surface of projector is 2 mSv/hr for one projector. Assume the
distance is at 0.01 meter from external surface of projector.
I0= 5 x 2 mSv/hr
I0= 10 mSv/hr
I1 = [(D0)2 / (D1)2] x I0
I1 = 0.0025 mSv/hr
Consider I2 = I0 = 10 mSv/hr
For Ir-192
Concrete 48.3 mm
Steel 15.5 mm
Lead 4.8 mm
I0 / It = 2n
I5 = I0/2n
I5 = (10mSv/hr) / (21.45)
I5 = 3.68 mSv/hr
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Prepared by : MOHD HUZAIRI RUSLI @ 24/01/2018
I4 at fence
Distance x
Depth = 1.5 meter
I5 1.6 meter
I4 = [(D5)2 / (D4)2] x I0
n = (10mm/15.5mm) = 0.65
I1 / I3 = 2n
I3 = I1/2n
I3 = (0.0025mSv/hr) / (20.65)
I3 = 0.002 mSv/hr
I7 = I6/2n
I7 = (0.0025mSv/hr) / (21.45)
I7 = 0.0009 mSv/hr
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Prepared by : MOHD HUZAIRI RUSLI @ 24/01/2018
I0 Projector surface 10
I2 Internal surface of 10
concrete
Note:
Refer table above. The dose rate of radiation intensity at I3,I4 and I7 is below 0.5 mSv/hr
(maximum dose rate for public). Hence, this bunker design is safe for use.
The thickness of concrete floor is optional since the dose rate at fence is below 0.5 mSv/hr.
For security purpose, the bomb-pit will use good quality of padlock for both steel closure at
main door.
Only approved worker are allowed to entering this bompit.
The use of bomb-pit will follow the regulation enforced by AELB.
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Prepared by : MOHD HUZAIRI RUSLI @ 24/01/2018
roof
Fence/concrete
wall
bompit
ground ground
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