Output interpretation

Jump to: navigation, search

All FISPACT-II calculations possess at least two output files: an output file [fileroot].out and a runlog file [fileroot].log. The output contains a sequence of text outputs which are summarised in the following sections.

Header and run information

The output file always begins with a header identifying the release version of the code:

     |                                                                            |
     |                            F I S P A C T - I I                             |
     |                            -------------------                             |
     |                                                                            |
     |                  Transmutation-Activation Inventory Code                   |
     |                   United Kingdom Atomic Energy Authority                   |
     |                                                                            |
     |                           Release 3.00 September 2015                      |
     |           Copyright (c) 2009-15, UK Atomic Energy Authority                |
     |                                                                            |

     Source CVS Tag: $Name: Release-3-00-00 $

after which a run identification box is printed with a summary of the nuclear data, user input and simulation data. Note that only the initial nuclear data are identified here, although simulations with multiple nuclear data and/or spectra will have these summarised at the end of the output.

Printed after the header information is the box containing unique identifying information for the run, for example with a simulation of the Fusion Neutron Source (FNS) 5 minute irradiation of Inconel-600 at position #3 (part of the FISPACT-II fusion decay heat validation:

     |                                                                                                       |
     |                      R U N   I D E N T I F I C A T I O N   I N F O R M A T I O N                      |
     |                                                                                                       |
     | INITIAL CROSS SECTION DATA                                                                            |
     | Collapsed library timestamp: 15:56:33 24 August 2015                                                  |
     | EAF source library label:                                                                             |
     | FLUX file label:             Position #3 Normalization Factor                                         |
     |                                                                                                       |
     | DECAY DATA                                                                                            |
     | Condensed library timestamp: 15:36:26 24 August 2015                                                  |
     | EAF source library label:    Decay input from separate files                                          |
     |                                                                                                       |
     | THIS RUN                                                                                              |
     | timestamp:                   09:26:29 26 August 2015                                                  |
     | fileroot :                   inventory                                                                |
     | name of FILES file:          files                                                                    |
     | FISPACT title:               * FNS 5 Minutes Inconel-600                                              |
     |                                                                                                       |
     | See the inventory.log file                                                                            |
     | and summary details at the end of this file for further information on files used by this run         |
     |                                                                                                       |

ATOMS output data

Each instance of the ATOMS keyword in the input file cause the output of a set of data in the output file:

  1. Table keys (first ATOMS only)
  2. The time line
  3. Iron information (if IRON is used)
  4. The inventory, including:
    • The heading line
    • A line for each nuclide above the MIND threshold
    • Nuclide table totals
    • Inventory summary
  5. Inventory by element (if NOCOMP is not used)
  6. Gamma spectra
  7. Gamma-dose totals
  8. Dominant nuclide lists (if NOSORT is not used)
  9. Bremsstrahlung corrections (if BREMSSTRAHLUNG is used)

Table key

Prior to the first inventory tables output initiated by the ATOMS keyword the following key is printed:

  | NB: IN FOLLOWING TABLES                                                     |
  |                         ? MEANS CONVERGENCE NOT REACHED FOR NUCLIDE         |
  |                         # MEANS NUCLIDE IS STABLE                           |
  |                         > MEANS NUCLIDE WAS PRESENT BEFORE IRRADIATION      |
  |                                                                             |
  |                                                                             |
  V                                                                             V

This key lists four single character flags that are printed immediately following each nuclide identifier. (Note that the * that was present in legacy FISPACT versions has been made obsolete, as the equilibrium approximation is not required by the LSODES solver used by FISPACT-II):

  • ? is the convergence flag whose presence indicates a nuclide with larger uncertainty in its inventory. It is set if the error for the nuclide is greater that 1.5 times the rms norm error set by the rtol and atol flags (see TOLERANCE). If this flag is set for nuclides that appear in the dominant nuclide table, then results should be treated with great caution until convergence studies have been performed or tighter TOLERANCE settings are used to remove the flag.
  • & indicates that no gamma-spectral data were present in the decay data library and that the keyword SPEK was used to calculate a spectrum approximately. If most of the gamma dose-rate is produced from nuclides with this flag then the result should be treated with great caution.
  • # indicates that the nuclide is stable.
  • > indicates that this nuclide was present in the material input, specified by the MASS or FUEL keyword.

Time line and nuclide inventory

The time line is printed at the start of the output produced at the end of an integration step initiated by the ATOMS or SPECTRUM keyword. It displays the time interval number, the step length and the total elapsed time. The ZERO keyword causes the elapsed time counter to be reset to zero, and the word COOLING to be added to the time line, for example:

* * * TIME INTERVAL   2 * * * * * * * TIME IS   3.0000E+02 SECS OR  5.0000E+00 MINS  * * * ELAPSED TIME IS   5.000 m   * * * FLUX A
NUCLIDE        ATOMS         GRAMS        Bq       b-Energy    a-Energy   g-Energy    DOSE RATE   INGESTION  INHALATION   HALF LIFE
                                                      kW          kW         kW         Sv/hr      DOSE(Sv)    DOSE(Sv)    second

H   1    #  2.04274E+10   3.419E-14   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable
H   2    #  3.37468E+08   1.129E-15   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable
H   3       6.30806E+05   3.159E-18   1.124E-03   1.028E-21   0.00E+00   0.000E+00   0.000E+00   4.720E-14   2.922E-13   3.891E+08
He  3    #  1.49099E+05   7.467E-19   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable
He  4    #  3.00423E+09   1.997E-14   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable
Ti 46    #  2.97170E+05   2.268E-17   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable
Ti 47    #  2.20319E+07   1.718E-15   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable
Ti 48    #  8.25936E+05   6.576E-17   0.000E+00   0.000E+00   0.00E+00   0.000E+00   0.000E+00   0.000E+00   0.000E+00     Stable

The inventory contains up to eleven columns of data (excluding the nuclide identifier and flags) giving values at the end of the step indicated by the time line. The first seven of these are always printed, and their contents are defined in the table below, where

  • \(A_{r,i}\) is the atomic weight of isotope \(i\) in amu
  • \(N_A\) is the Avogadro constant (mol\(^{-1}\)
  • \(E_{\beta ,i}\) is the beta decay energy for isotope \(i\) (eV)
  • \(E_{\alpha ,i}\) is the alpha decay energy for isotope \(i\) (eV)
  • \(E_{\gamma ,i}\) is the gamma decay energy for isotope \(i\) (eV)
  • \(C_1\) is the conversion factor from eV to kJ

Note that the heat column headings used in legacy FISPACT versions is retained, although the columns contain values of power (kW).

Entries in columns 1-7 of the FISPACT-II inventory output table
Column Description Value Units
1 number of atoms \(N_i\)
2 mass \(N_i A_{r,i} / N_A\) g
3 activity \(A_i = N_i \lambda_i \) Bq
4 \(\beta\)-heat \(A_i E_{\beta , i} C_1\) kW
5 \(\alpha\)-heat \(A_i E_{\alpha , i} C_1\) kW
6 \(\gamma\)-heat \(A_i E_{\gamma , i} C_1\) kW
7 dose rate contact or point Sv h\(^{-1}\)

The remaining four columns are specified by using the HAZARDS, CLEAR, ATWO and HALF keywords. The contents of these columns are defined in the table below. Note that the clearance index is defined as a dimensionless quantity in FISPACT-II rather than as a quantity of dimension mass (kg) as used in legacy versions, so different results will be seen for input masses different from 1 kg. In the table the quantities:

  • \(e^{ing}_i , e^{inh}_{i}\) are the factors to convert activity of an ingested or inhaled nuclide into the dose (units of Sv) received by an average person over 50 years. These factors are tabulated in the hazards input data.
  • \(L_i\) specific activity (in Bq kg\(^{-1}\) below which a material is given clearance for disposal. Values of \(L_i\) are tabulated in the clear input data.
  • \(m_{tot}\) total mass of material (kg)
  • \(A_{2,i}\) activity level for safe transport. Values of \(A_{2,i}\) in TBq are tabulated in the a2 input data.
  • \(C_2\) is the conversion factor from TBq to Bq
Keywords and the entries that they cause to be printed in columns 8-11 of the inventory output table.
Column Description Value Units
HAZARDS ingestion dose \(A_i e^{ing}_i\) Sv
inhalation dose \(A_i e^{inh}_i\) Sv
CLEAR clearance index \(A_i / (m_{tot} L_i) \)
ATWO transport index \(A_i / (A_{2,i} C_2) \)
HALF half-life \(\lambda^{-1}_i\) log\(_e\)2 or 'Stable' s

Inventory step summary

The step summary appears after the table of values for individual nuclides. The first line contains the number of nuclides [math]N_n[/math] printed in the preceding table and the remaining lines give sums over nuclides of various diagnostic quantities. The first three of these lines contain:

  • The total activity in curies
    [math]\mathtt{TOTAL~CURIES} = C_3\sum_{i=1}^{N_n} A_i[/math]
    where [math]C_3=1/(3.7\times10^{10})[/math] is the conversion factor from Bq to Ci.
  • The total alpha power in Ci-MeV
    [math]\mathtt{TOTAL~ALPHA} = 10^{-6}C_3\sum_{i=1}^{N_n} A_i E_{\alpha,i}[/math]
    where the [math]10^{-6}[/math] is the conversion factor from eV to MeV.
  • The total beta power in Ci-MeV
    [math]\mathtt{TOTAL~BETA} = 10^{-6}C_3\sum_{i=1}^{N_n} A_i E_{\beta,i}[/math]
  • The total gamma power in Ci-MeV
    [math]\mathtt{TOTAL~GAMMA} = 10^{-6}C_3\sum_{i=1}^{N_n} A_i E_{\gamma,i}[/math]

For example, these are output as


               CURIE-MeV     CURIE-MeV     CURIE-MeV
4.16621E-05   0.00000E+00   3.17526E-05   4.06607E-05

Activity break-down, fission and hazards

The next line splits the total activity into parts associated with [math]\alpha[/math], [math]\beta[/math] and [math]\gamma[/math] decays according to their decay type. To be precise, the exact definition follows, using the decay identifiers of FISPACT-II which have a one-to-one correspondence with ENDF-6 RTYP values (see the decay identification page for details). Activity from decays with type IRT = 4 is assigned to the ALPHA BECQUERELS total, activity from those with IRT = 1, 11, 16, 17, 20, 2, 14, 19 is assigned to the BETA BECQUERELS total and from those with IRT = 3 to GAMMA BECQUERELS. Activity from decays with IRT = 12 or 13 is split between the [math]\alpha[/math] and [math]\beta[/math] totals, and activity from decays with IRT = 15 is split between the [math]\alpha[/math] and [math]\gamma[/math] totals. An example output would be:

ALPHA BECQUERELS = 0.000000E+00  BETA BECQUERELS = 8.730359E+05  GAMMA BECQUERELS = 4.686934E+05

                                     3.05334E-07 Ci/cc           DENSITY   8.42E+00 gm/cc

                                     3.05334E-07 Ci/cc

TOTAL BETA  HEAT PRODUCTION          1.54269E-10 kW
TOTAL GAMMA HEAT PRODUCTION          2.01236E-10 kW              TOTAL HEAT PRODUCTION 3.55505E-10 kW
INITIAL TOTAL MASS OF MATERIAL       1.00000E-03 kg              TOTAL HEAT EX TRITIUM 3.55505E-10 kW

TOTAL MASS OF MATERIAL               1.00000E-03 kg
NEUTRON  FLUX DURING INTERVAL        0.00000E+00 n/cm**2/s
NUMBER OF FISSIONS                   0.00000E+00                 BURN-UP OF ACTINIDES  0.00000E+00 %


The TOTAL ACTIVITY FOR ALL MATERIALS item gives total activity in Bq, and the TOTAL ACTIVITY EXCLUDING TRITIUM is the total with tritium activity excluded. The HEAT PRODUCTION items are the sums over all materials of the respective \(\alpha\)-, \(\beta\)- and \(\gamma\)-powers, the total of these three powers, and the total with the contribution of tritium decay excluded.

The NUMBER OF FISSIONS is a count of the change of the number of nuclides that may undergo fission from the number in the the initial inventory. These nuclides are identified as those with the MT=18 reaction on their list of reactions. BURN-UP OF ACTINIDES gives the percentage of the initial number of fissionable nuclides that have been burnt up.

Note that NUMBER OF FISSIONS may become negative if, for example, there are no nuclides with MT=18 initially but ones are created by irradiation of the initial inventory. All nuclides with MT=18 reactions are counted, even if their reactions are excluded because USEFISSION is absent, or reactions are excluded by the FISYIELD keyword or reactions are excluded because their fission yield data are not available.

The remaining items in the summary list depend upon the use of the ATWO, CLEAR and HAZARDS keywords, and on whether the DENSITY keyword was used.

If the ATWO keyword is used in the input file, then table items TOTAL Bq/A2 RATIO and EFFECTIVE A2 are displayed, where

[math] \mathtt{TOTAL~Bq/A2~RATIO} = \sum_{i=1}^{N_n} \left( \frac{A_i}{A_{2,i}C_2} \right) [/math] and EFFECTIVE A2 is the ratio of the total activity to (TOTAL Bq/A2 RATIO).

If the CLEAR keyword is used in the input file, then the A2 values are replaced by

[math] \mathtt{CLEARANCE~INDEX} = \sum_{i=1}^{N_n} \left( \frac{A_i}{M_{tot}L_i} \right) [/math]

The HAZARDS keyword causes the total ingestion and inhalation doses, and the total doses excluding the contribution from tritium to be printed. The DENSITY keyword causes the density (in g cm\(^{-3}\)) to be printed.


The displacements per atom (DPA) for mixtures of elements with different lattice displacement energies, the total displacements rate, [math]D_{tot}[/math] may be estimated using the ratio of the mean total available energy to the mean displacement energy:

[math] D_{tot} = e_{d}\phi \sum_{i=1}^{N_n} N_i \bar{d}_i / 2\bar{E}_d [/math]

where \(\phi\) is the flux amplitude in cm\(^{-2}\) s\(^{-1}\), \(N_i\) is the number of atoms of nuclide \(i\) and \(\bar{d}_i\) is the collapsed dpa reaction cross-section in eV-cm\(^2\). The constant \(e_{d}\) is the DPA efficiency factor and is set to 80%. A list of the dpa cross-sections recognised by FISPACT-II is given in this table.

The mean atomic displacement energy [math]\bar{E}_d[/math] is given by

[math] \bar{E}_d=\sum_{i=1}^{N_n} N_i E_d(Z_i) / \sum_{i=1}^{N_n} N_i [/math]

\(Z_i\) is the atomic number of nuclide \(i\) and \(E_d\) are atomic displacement energies (in eV). These are set as 25 eV by default, with a set of altered valued summarised in the table below. Note that these can be overwritten with the use of ATDISPEN and ALLDISPEN to any user-supplied values.

Atomic displacement energies used to compute DPA. \(E_d\) is set at 25 eV for all other elements.
Element Displacement energy \(E_d\) (eV)
Be 31
Co 40
C 31
Ni 40
Mg 25
Cu 40
Al 27
Zr 40
Si 25
Nb 40
Ca 40
Mo 60
Ti 40
Ag 60
V 40
Ta 90
Cr 40
W 53
Mn 40
Au 30
Fe 40
Pb 25

Alternatively, the displacement rate may be estimated using the mean of the displacement rates of the constituents:

[math] D_{tot} = e_{d}\phi \sum_{i=1}^{N_n} N_i \bar{d}_i / 2 E_d(Z_i) [/math]

Both options have been evaluated and have been shown to give similar results. The displacements per atom is given by dividing this by the total number of atoms:

[math] \mathtt{DPA~RATE} = D_{tot} / \sum_{i=1}^{N_n} N_i [/math]

The kinetic energy released in materials rates are given by

[math] \mathtt{KERMA~RATE} = \phi \sum_{i=1}^{N_n} N_i \bar{\kappa}_i [/math]

where \(\bar{\kappa}_i\) is the collapsed kerma cross-section for one of the kerma cross-sections listed in this table. Specific values of this energy per kilogram and per cm\(^3\) are obtained by scaling the total kerma using the initial mass and density.

Gas production rates (in s\(^{-1}\)) are given by

[math] \mathtt{GAS~RATE} = \phi \sum_{i=1}^{N_n} N_i \bar{\sigma}_i^{gas} [/math]

where \(\bar{\sigma}_i^{gas}\) is the collapsed total gas production cross-section in cm\(^2\). A list of the total gas production cross-sections recognised by the code is given in this table. If there is gas production from decays, then there will be corresponding rates (e.g., GAS RATE (a decay)) printed. If any of the kerma, dpa or gas appm rates are zero, then their production rates are not printed.

The final part of the summary output table is the gas atoms parts per million for the five secondary gas nuclides:

   APPM OF He  4    =  2.8571E-07
   APPM OF He  3    =  1.4180E-11
   APPM OF H   3    =  5.9991E-11
   APPM OF H   2    =  3.2094E-08
   APPM OF H   1    =  1.9427E-06

Elemental inventory

The composition of material by element is the next table displayed. The column headings for this are: number of atoms of the element, number of gram-atoms, number of grams, \(\beta\) power output (Curie-MeV and kW), \(\gamma\) power output (Curie-MeV and kW) and \(\alpha\) power output (Curie-MeV and kW).

                                               COMPOSITION  OF  MATERIAL  BY  ELEMENT
                                                            BETA                     GAMMA                     ALPHA
                     ATOMS      GRAM-ATOMS     GRAMS      CURIES-MeV      kW        CURIES-MeV      kW        CURIES-MeV      kW

    1      H       2.0766E+10   3.4482E-14   3.5318E-14   1.7334E-16   1.0276E-21   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00
    2      He      3.0044E+09   4.9889E-15   1.9968E-14   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00
   22      Ti      2.1825E+08   3.6241E-16   1.7711E-14   6.2424E-08   3.7005E-13   2.6189E-08   1.5525E-13   0.0000E+00   0.0000E+00
   23      V       9.4118E+08   1.5629E-15   7.9552E-14   2.6319E-05   1.5602E-10   3.5726E-05   2.1178E-10   0.0000E+00   0.0000E+00
   24      Cr      1.8496E+21   3.0714E-03   1.5970E-01   2.8493E-07   1.6891E-12   6.2813E-08   3.7236E-13   0.0000E+00   0.0000E+00
   25      Mn      4.2751E+19   7.0989E-05   3.9000E-03   7.1260E-07   4.2243E-12   8.8035E-07   5.2187E-12   0.0000E+00   0.0000E+00
   26      Fe      8.4328E+20   1.4003E-03   7.8200E-02   1.0757E-07   6.3770E-13   1.2886E-07   7.6389E-13   0.0000E+00   0.0000E+00
   27      Co      1.7758E+10   2.9488E-14   1.6949E-12   4.2516E-06   2.5204E-11   3.6646E-06   2.1724E-11   0.0000E+00   0.0000E+00
   28      Ni      7.7794E+21   1.2918E-02   7.5820E-01   1.4220E-08   8.4299E-14   1.7238E-07   1.0219E-12   0.0000E+00   0.0000E+00
   29      Cu      3.0080E+03   4.9950E-21   3.2431E-19   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00   0.0000E+00

Gamma spectra

In this section the total powers (MeV s\(^{-1}\)) from \(\alpha\), \(\beta\) and \(\gamma\) radiations and the total number of spontaneous fission neutrons are listed followed by two columns giving the \(\gamma\) spectrum (MeV s\(^{-1}\) per group) and number of gammas per group (cm\(^{-3}\) s\(^{-1}\)) in either a 24- or 22-group form, depending on the parameter used for GROUP.

Note that starting with version 3-20-00 the output gamma group can be altered with a user-supplied group structure using the READGG keyword. This could instead be set to the number of channels in a gamma spectrometer or some bespoke group structure to capture essential lines in a gamma spectrum.

                                               GAMMA SPECTRUM AND ENERGIES/SECOND

     NEUTRONS PER SECOND ARISING FROM SPONTANEOUS FISSION                    0.00000E+00    Entered density (g/cc)       8.42
     POWER FROM ALPHA PARTICLES (MeV per Second)                             0.00000E+00
     POWER FROM BETA  PARTICLES (MeV per Second)                             1.17485E+06
     TOTAL GAMMA POWER FROM ACTIVATION  (MeV per Second)                     1.50445E+06    Total gammas (per cc per s)      1.16192E+07
     GAMMA RAY POWER FROM ACTIVATION DECAY  MeV/s        ( 0.00- 0.01 MeV)   1.06093E+03    Gammas per group (per cc per s)  1.78661E+06
                                                         ( 0.01- 0.02 MeV)   1.42317E+01                                     7.98872E+03
                                                         ( 0.02- 0.05 MeV)   4.70931E-01                                     1.13292E+02
                                                         ( 0.05- 0.10 MeV)   8.70788E+02                                     9.77604E+04
                                                         ( 0.10- 0.20 MeV)   4.05257E+02                                     2.27484E+04
                                                         ( 0.20- 0.30 MeV)   3.46709E+02                                     1.16772E+04
                                                         (10.00-12.00 MeV)   0.00000E+00                                     0.00000E+00
                                                         (12.00-14.00 MeV)   0.00000E+00                                     0.00000E+00
                                                         (14.00-20.00 MeV)   0.00000E+00                                     0.00000E+00

The total dose rate is then given in one of two forms depending on the DOSE parameter; these two outputs are for contact dose from a semi-infinite slab of the material and for the dose from a point source at a specified distance. Note that if most of the dose rate is produced by nuclides with an approximated gamma spectrum, then the following warning message will be given:

                               DOSE AND GAMMA SPECTRUM WITH CAUTION ***

Dominant nuclides

At each step the inventory is sorted into descending order of radiological quantities and tables of nuclides at the tops of these lists are printed (see the SORTDOMINANT keyword). In all cases, dominant nuclides, as measured by activity, total heat production, dose rate, gamma heating and beta heating are displayed. If the HAZARDS keyword is used, nuclides are also sorted by ingestion and inhalation dose, and CLEAR adds columns with sorting by clearance index.

                                                                           DOMINANT NUCLIDES

                  (Bq)      ACTIVITY             (kW)       HEAT              (Sv/hr)    DOSE RATE            (Sv)      INGESTION ..
       Total   1.2507E+14             Total   3.6006E-02             Total   5.6310E+04             Total   1.3853E+05            ..
    1  Sc 48   4.3656E+13  34.91E+00  Sc 48   2.4964E-02  69.33E+00  Sc 48   4.1357E+04  73.45E+00  Sc 48   7.4216E+04  53.57E+00 ..
    2  Sc 46   2.4682E+13  19.73E+00  Sc 46   8.3894E-03  23.30E+00  Sc 46   1.3625E+04  24.20E+00  Sc 46   3.7023E+04  26.73E+00 ..
    3  Ca 45   1.9657E+13  15.72E+00  Sc 47   8.4082E-04  23.35E-01  Sc 50   5.4522E+02  96.83E-02  Ca 45   1.3956E+04  10.07E+00 ..
    4  Sc 47   1.9369E+13  15.49E+00  Sc 50   4.6108E-04  12.81E-01  Ti 45   3.2266E+02  57.30E-02  Sc 47   1.0459E+04  75.50E-01 ..

Bremsstrahlung corrections

If the BREMSSTRAHLUNG keyword is used, then the Bremsstrahlung correction to the gamma dose is calculated using either plane or point source formulae and are printed as shown below for fispQA test116 within the Tst_709 folder.


    Bremsstrahlung dose rate from  Ar 39  is 8.68701E-08 Sv/h  ( 8.68701E-06 Rems/h). This is  1.50849E-10% of the total dose rate.

    Bremsstrahlung dose rate from  Ar 42  is 1.99365E-06 Sv/h  ( 1.99365E-04 Rems/h). This is  3.46196E-09% of the total dose rate.

    Bremsstrahlung dose rate from  K  42  is 1.17442E-01 Sv/h  ( 1.17442E+01 Rems/h). This is  2.03937E-04% of the total dose rate.

    Bremsstrahlung dose rate from  Cl 38  is 3.41852E-06 Sv/h  ( 3.41852E-04 Rems/h). This is  5.93623E-09% of the total dose rate.