Bi207

["Denis J. Rinkacs Jr." <dr4i+@andrew.cmu.edu>]

Hey thanks for the responses, there is some difference in answers (i.e.
41mCi - 60mCi).  Here is what I did and my results:

I used the 1970 edition of the RHH to get the equation and gamma energies

R/hr @ 1ft = 6 C E n

where    C = # Ci's
         E = gamma energy in MeV
         n = gamma quanta/dis

C = 0.6R/hr / 6En

where 6En = 6 * ((0.57 * 0.98) + (1.1 * 0.77) + (1.8 * .09))

          = 6 * (0.5586 + 0.847 + 0.162)

          = 6 * 1.5676

          = 9.4056

goto original equation

C = 0.6 / 9.4056

  = 0.06379

  = 63.8 mCi

The instrument that I used was a Victoreen model 470A.

Thanks

Denny Rinkacs
Rad Safety
CMU

PS sorry about the 35mR/hr or 35R/hr, it is in fact reading 35 R/Hr on
contact with the above mentioned instrument.