Radioactive Decay and Dose


  • The mass on a particle is reduced using the time constant approach
  • The decay constant is defined by the half-life
  • Doses are computed from published conversion factors by radionuclide
  • There are limitations to this simple approach:
    • Decay does not start until the particle is emitted
    • For continuous emissions, the emission rate must be decay corrected
    • Concentration and deposition are decayed during the calculation
    • Concentration and deposition are NOT decayed after file output



captex_control.txt

   load control file

captex_setup.txt

   load setup file

25

   run duration



C137

   pollutant ID

1.0E+16

   emission rate (Bq)

1.0

   emission hours

c137.bin

   output grid name

2

   number of levels

0 100

   height of levels

Select Cs-137




2.6E-11

   deposition multiplier (1.1E-12 rem/h x 24h)

1.0E-10

   concentration multiplier 3.4E-11 rem/h x 3h)

Dose Equivalent

   border labels map type

REM

   border labels mass units




24-h dose

1-year dose

9.6E-09

   deposition multiplier (1.1E-12 rem/h x 8760h)