1. Temporary shielding for the 20" vertical penetration Igor Rakhno November 17, 2008

2. Vertical vent in MTA hall, 20 " (elevation view) 2

3. Vertical vent in MTA hall, 20 " (cross section) 3

4. Plan view of the temporary shielding 4

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7. 1-cm Cu target (10% of I.L.) @ 1 Hz (DC loss) Calculated dose on top of the temporary shielding is 50 mrem/hr Calculated dose at the opening is 80 mrem/hr → extra bent section(0.1) Calculated dose near the side walls is 10 mrem/hr When considering a 100% I.L. target and rep.rate of 3 pulses per minute (1 pulse every 20 sec), one gets approximately 50 × 10 / 20 = 10 mrem/hr Radiation area (fencing) 7

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10. Shielding block in the access pit (cross section) 10

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