Linac Neutrons In Maze

[Chris Hawkins <chawkins@inet.guthrie.org>]

I'm looking for comments on the 2 methods for calculating
neutron mrem at the door to the maze in a linac room.  (NCRP
79 pp 52-7)

I've done it using the Kersey method using a TVL
(tenth-value length) of 5 m in the maze, and got 370 & 385
mrem/wk (2 different locations for entrance to maze)

I then used the McCall's albedo method and got 98.7 mrem/wk.

The room geometry is close to Fig 34a (the "poor" one) on
p53, with a maze wall (room door to end) of just 7 feet.

Does this roughly 4 to 1 difference agree with others'
experiences??

What are other people doing ??

Thanks in advance.
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       /   Chris Hawkins                   717.882.4048
      /   Radiation Oncology          fax 717.882.5166
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