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Correction Factors for Use with ICRP 

Publication 116 Isotropic and Rotational 

Dose Conversion Coefficients

ORAUT-RPRT-0068 Rev. 00

Effective Date: 07/11/2016

Supersedes: None

Subject Expert(s): Richard J. Traub, Matthew H. Smith, Keith A. McCartney

Document Owner 

Approval: Signature on File

Matthew H. Smith, Document Owner

Approval Date: 06/03/2016

Concurrence: Signature on File

John M. Byrne, Objective 1 Manager

Concurrence Date: 06/02/2016

Concurrence: Signature on File

Edward F. Maher, Objective 3 Manager

Concurrence Date: 06/02/2016

Concurrence: Dianne Poncio Signature on File for

Kate Kimpan, Project Director

Concurrence Date: 06/06/2016

Approval: Signature on File

James W. Neton, Associate Director for Science

Approval Date: 07/11/2016

FOR DOCUMENTS MARKED AS A TOTAL REWRITE, REVISION, OR PAGE CHANGE, REPLACE THE PRIOR 

REVISION AND DISCARD / DESTROY ALL COPIES OF THE PRIOR REVISION. 

New Total Rewrite Revision Page Change
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 2 of 63

 

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION

NUMBER DESCRIPTION

07/11/2016 00 New document initiated for evaluation of correction factors for use 

with ICRP Publication 116 rotational dose conversion coefficients 

and for neutron irradiations which includes information for use with 

ICRP Publication 110 isotropic dose conversion coefficients. 

Incorporates formal internal and NIOSH review comments. Training 

required: As determined by the Objective Manager. Initiated by 

Matthew H. Smith. 

TRADEMARK INFORMATION

MCNP6TM is a trademark of Regents of the University of California, Los Alamos National Laboratory, 

in the United States and/or other countries.

All other trademarks are the property of their respective owners.
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 3 of 63

 

TABLE OF CONTENTS

SECTION TITLE PAGE

Acronyms and Abbreviations ............................................................................................................... 6

1.0 Introduction .............................................................................................................................. 7

2.0 Methods and Approach ............................................................................................................ 7

2.1 Phantoms ..................................................................................................................... 8

2.2 Dosimeters ................................................................................................................... 9

2.3 Calculations.................................................................................................................. 9

2.4 Benchmark Calculations............................................................................................... 9

2.5 Irradiation Geometry Factors ........................................................................................ 9

3.0 Results................................................................................................................................... 10

3.1 Benchmark calculations.............................................................................................. 10

3.2 Irradiation Geometry Factors ...................................................................................... 10

3.2.1 Photon Irradiations....................................................................................... 10

3.2.2 Neutron Irradiations...................................................................................... 13

3.3 Angular Response...................................................................................................... 16

4.0 Discussion ............................................................................................................................. 17

5.0 Summary ............................................................................................................................... 18

References ........................................................................................................................................ 19

ATTACHMENT A DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL 

PHANTOM...................................................................................................... 20

ATTACHMENT B DOSIMETER LOCATIONS ON THE ADULT MALE VOXEL PHANTOM ........ 27

ATTACHMENT C EXAMPLE MCNP6 INPUT FILE ..................................................................... 32

ATTACHMENT D RESULTS OF REFERENCE CALCULATIONS............................................... 54

LIST OF TABLES

TABLE TITLE PAGE

2-1 Dimensions of the ICRP Publication 110 voxel phantoms ........................................................ 8

2-2 Dosimeter locations.................................................................................................................. 9

3-1 Estimated ROT IGFs for monoenergetic photons incident on a voxel phantom...................... 13

3-2 Estimated ISO IGFs for monoenergetic photons incident on a voxel phantom ....................... 13

3-3 Estimated ROT IGFs for monoenergetic neutrons incident on a voxel phantom..................... 16

3-4 Estimated ISO IGFs for monoenergetic neutrons incident on a voxel phantom ...................... 16
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LIST OF FIGURES

FIGURE TITLE PAGE

3-1 IGFs for uncollided photons in dosimeter regions when the adult female voxel phantom 

is irradiated in the ROT geometry by monoenergetic photons ................................................ 11

3-2 IGFs for uncollided photons in dosimeter regions when the adult female voxel phantom 

is irradiated in the ISO geometry by monoenergetic photons ................................................. 11

3-3 IGFs for uncollided photons in dosimeter regions when the adult male voxel phantom is 

irradiated in the ROT geometry by monoenergetic photons.................................................... 12

3-4 IGFs for uncollided photons in dosimeter regions when the adult male voxel phantom is 

irradiated in the ISO geometry by monoenergetic photons..................................................... 12

3-5 IGFs for uncollided neutrons in dosimeter regions when the adult female voxel phantom 

is irradiated in the ROT geometry by monoenergetic neutrons............................................... 14

3-6 IGFs for uncollided neutrons in dosimeter regions when the adult female voxel phantom 

is irradiated in the ISO geometry by monoenergetic neutrons ................................................ 14

3-7 IGFs for uncollided neutrons in dosimeter regions when the adult male voxel phantom is

irradiated in the ROT geometry by monoenergetic neutrons .................................................. 15

3-8 IGFs for uncollided neutrons in dosimeter regions when the adult male voxel phantom is 

irradiated in the ISO geometry by monoenergetic neutrons.................................................... 15

3-9 Rotational dependence of fluence at four dosimeter locations for uncollided 0.2-MeV 

photons..................................................................................................................................17

A-1 Elevation view of the adult female voxel phantom showing the center chest dosimeter 

location ..................................................................................................................................21

A-2 Plan view of the adult female voxel phantom showing the center chest dosimeter 

location ..................................................................................................................................22

A-3 Elevation view of the adult female voxel phantom showing the left collar dosimeter 

location ..................................................................................................................................22

A-4 Plan view of the adult female voxel phantom showing the left collar dosimeter location ......... 23

A-5 Elevation view of the adult female voxel phantom showing the center waist dosimeter 

location ..................................................................................................................................23

A-6 Plan view of the adult female voxel phantom showing the center waist dosimeter location .... 24

A-7 Elevation view of the adult female voxel phantom showing the left chest pocket 

dosimeter location..................................................................................................................25

A-8 Plan view of the adult female voxel phantom showing the left chest pocket dosimeter 

location ..................................................................................................................................26

B-1 Elevation view of the adult male voxel phantom showing the center chest and center 

waist dosimeter locations ....................................................................................................... 28

B-2 Plan view of the adult male voxel phantom showing the center chest and left chest 

pocket dosimeter locations..................................................................................................... 29

B-3 Plan view of the adult male voxel phantom showing the center waist dosimeter location ....... 29

B-4 Plan view of adult male voxel phantom showing the left collar dosimeter............................... 30

B-5 Elevation view of the adult male voxel phantom showing the left collar dosimeter location..... 30

B-6 Elevation view of the adult male voxel phantom showing the left chest pocket dosimeter 

location ..................................................................................................................................31

D-1 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic neutrons, AP geometry ................................. 57

D-2 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic neutrons, AP geometry .................................... 57

D-3 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic neutrons, ROT geometry............................... 58

D-4 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic neutrons, ROT geometry.................................. 58
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D-5 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic neutrons, ISO geometry ................................ 59

D-6 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic neutrons, ISO geometry................................... 59

D-7 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic photons, AP geometry................................... 60

D-8 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic photons, AP geometry ..................................... 60

D-9 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic photons, ROT geometry................................ 61

D-10 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic photons, ROT geometry................................... 61

D-11 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic photons, ISO geometry ................................. 62

D-12 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic photons, ISO geometry .................................... 62

D-13 Comparison between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, adult 

female and male urinary bladder wall, monoenergetic neutrons, AP geometry....................... 63
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ACRONYMS AND ABBREVIATIONS 

AP anterior-posterior

cm centimeter

DCC dose conversion coefficient

DOE U.S. Department of Energy

H*(10) ambient deep dose equivalent

Hp(10) personal deep dose equivalent

ICRP International Commission on Radiological Protection

IGF irradiation geometry factor

IREP Interactive RadioEpidemiological Program

ISO isotropic

keV kiloelectron-volt, 1,000 electron-volts

MCNP Monte Carlo n-particle

MeV megaelectron-volt, 1 million electron-volts

mm millimeter

NIOSH National Institute for Occupational Safety and Health

ORAU Oak Ridge Associated Universities

PA posterior-anterior

pSv picosievert

ROT rotational

SRDB Ref ID Site Research Database Reference Identification (number)
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1.0 INTRODUCTION

The purpose of this report is to provide guidance on the application of the organ dose conversion 

coefficients (DCCs) from International Commission on Radiological Protection (ICRP) Publication 116, 

Conversion Coefficients for Radiological Protection Quantities for External Radiation Exposures

(ICRP 2010). The DCCs in Publication 116 assume that the radiation beam is perpendicular (incident 

angle = 0) in relation to the personal deep dose equivalent [Hp(10)], ambient deep dose equivalent 

[H*(10)], and exposure measurements using either film badge or thermoluminescent dosimetry. While 

this assumption is reasonable and appropriate for the anterior-posterior (AP) exposure geometry, it 

could lead to an underestimate of the organ dose if appropriate irradiation geometry factors (IGFs) are 

not applied.

In a review conducted after a comment concern from the Advisory Board on Radiation and Worker 

Health (SC&A 2005), the National Institute for Occupational Safety and Health (NIOSH) determined 

that the rotational (ROT) and isotropic (ISO) DCCs as applied in OCAS-IG-001, External Dose 

Reconstruction Implementation Guideline (NIOSH 2007), could in fact lead to an underestimate of the 

external dose. The ISO geometry is of minor concern from a dose reconstruction standpoint because 

it is typically applied to the onsite ambient dose in which a person was not present during the 

measurement to effectively shield the dosimeter from low (<30 keV) and intermediate (30 to 250 keV) 

energy photons. However, if the ISO DCCs were applied to personal dosimeter measurements, they 

could result in an underestimate of the organ dose. Correction factors for ROT and ISO DCCs 

[applicable to the bone (red marrow and surface), esophagus, and lung] were published in Table 4.1.a 

of OCAS-IG-001, External Dose Reconstruction Implementation Guideline (NIOSH 2007), based on 

information in Study of a Selection of 10 Historical Types of Dosemeter: Variation of the Response to 

Hp(10) with Photon Energy and Geometry of Exposure (Thierry-Chef et al. 2002).

This report addresses the potential underestimate associated with the ROT and ISO DCCs for 

photons and neutrons and provides a method for determining irradiation geometry correction factors

(IGFs) based on Monte Carlo n-particle (MCNP) modeling of dosimeter response associated with 

placement on realistic phantoms as described in ICRP Publication 110, Adult Reference 

Computational Phantoms (ICRP 2009).

2.0 METHODS AND APPROACH

All calculations were performed using MCNP6 Version 1.0 (Pelowitz 2013). MCNP6.1 is a general 

purpose Monte Carlo radiation transport code. MCNP6.1 was chosen for these calculations because 

it is the only version of MCNP that the Los Alamos National Laboratory will continue to support in the 

future. Three irradiation geometries were considered for this report: AP, ROT, and ISO.

The AP geometry is defined by ICRP to be when the ionizing radiation is incident on the front of the 

body in a direction orthogonal to its long axis (ICRP 2010). To simulate an AP geometry for the 

irradiation of the phantoms, a single plane source (60 × 200 cm2

) was placed directly in front of the 

voxel phantom and the radiation particles were directed from the source to the voxel phantom.

The ROT geometry is defined to be when the body is irradiated by a parallel beam of ionizing 

radiation, which rotates at a uniform rate around the long axis from a direction orthogonal to the long 

axis of the body (ICRP 2010). To simulate a ROT geometry for irradiation of the phantoms, a single 

plane source (60 × 200 cm2

) was rotated at 5-degree intervals around the phantom. In the 0-degree 

rotation, the radiation particles are incident on the front of the body in a direction orthogonal to its long 

axis, and is the same as the AP geometry. The plane source was rotated around the voxel phantom 

via the TR card (a “card” is a set of data or instructions for input to MCNP; TR indicates surface 

coordinate transformation). Seventy-two TR cards were implemented in a single MCNP6 input file; 

the appropriate TR card for a particular history was determined by the SDEF card (SDEF indicates 
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source definition). In the 180-degree rotation, which is equivalent to the posterior-anterior (PA) 

geometry, the photons are incident on the back of the body in a direction orthogonal to its long axis. 

The 90-degree ROT geometry is equivalent to the left lateral geometry, and the 270-degree rotation is 

equivalent to the right lateral geometry.

The ISO geometry is defined by ICRP (2010) as being a radiation field in which the particle fluence 

per solid angle is independent of direction and location in space (ICRP 2010). To simulate an ISO 

geometry for irradiation of the phantoms, a single plane source (60 × 200 cm2

) was rotated around the 

phantoms such that the plane source was tangential to a uniformly located point on a sphere whose 

center was located at the approximate center of the voxel phantom. The coordinates of uniformly 

distributed points on the sphere were calculated using a Fibonacci grid function. Fibonacci grids were 

used because the points so chosen are very evenly distributed over the surface of the sphere 

(Hannay and Nye 2004; González 2009; Swinbank and Purser 2006). The source plane was rotated 

around the phantom via the TR card; the rotation matrix of the TR card was a function of the location 

of the point. One hundred TR cards were implemented in a single MCNP6 input file; the appropriate 

TR card for a particular history was determined by the SDEF card. Three independent sets of TR 

cards were prepared and run so that the ISO data in this report are based on 300 uniformly distributed 

points.

In agreement with Publication 116 (ICRP 2010), the radiation source and voxel phantom were placed 

in a vacuum. 

2.1 PHANTOMS

For these calculations, the adult female and adult male computational voxel phantoms, described in 

Publication 110 (ICRP 2009), were each implemented in MCNP6 (Pelowitz 2013) as a type 1 lattice.

A voxel phantom is a three-dimensional object that consists of a large number of voxels. Each voxel 

in a given phantom is the same size (see Table 2-1). The position, chemical composition, and density 

of each voxel are not explicitly encoded in a phantom. However, the position of a voxel is inferred 

based on its position relative to the other voxels in the phantom. The elemental composition and 

density of a voxel is inferred from a single digit that represents the tissue type of that voxel. Thus, a 

file that contains a voxel phantom consists of a large number of integers, where each integer is the 

index number of a tissue type. In the ICRP phantoms, the file consists of integers that range from 0 to 

141. The zero (0) tissue type is a void, or air that surrounds the actual phantom. When implemented 

in MCNP6, the tissue type is interpreted as a universe that fills a lattice. Because universe number 

zero is defined as the highest level universe, it was necessary to renumber all zeros to something 

else. For the NIOSH Project, all zeros were converted to 256. The size of the individual voxel is 

encoded in the MCNP6 input file. The voxel dimensions of the two phantoms are shown in Table 2-1. 

Note that the two phantoms have different voxel dimensions and the number of voxels in the adult 

female phantom is approximately twice that of the adult male phantom. The ICRP phantom 

distribution files also contain tabs that were removed from the file.

Table 2-1. Dimensions of the ICRP Publication 110 voxel phantoms. 

Dimension Adult female phantoma Adult male phantoma

Rows 137 127

Columns 299 254

Slices 348 222

Volume 1.775 × 1.775 × 4.84 mm3 2.137 × 2.137 × 8.0 mm3

a. The voxel phantoms are type 1 lattices.

The phantom files were also converted to a compact form that used the “nR” feature for horizontal 

data to reduce the size of the input file and to allow MCNP6 to read the adult female phantom file. It 
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had been observed that MCNPX, a version of MCNP that preceded MCNP6, would display error 

messages if a phantom of a certain number of voxels was presented to MCNPX and its Visual Editor 

(Vised) in the standard horizontal data card format.

2.2 DOSIMETERS

Four dosimeter locations were implemented for the calculations. The dosimeter location is an empty 

(void) rectangular parallelepiped 5.08 × 5.08 × 0.2 cm3 in size. The locations are center chest, left 

collar, center waist, and left chest pocket. These locations were taken to approximate the standard 

locations of the dosimeters on a worker (see Table 2-2). Two-dimensional drawings that show the 

location of the dosimeters on the adult female and adult male phantoms are provided in 

Attachments A and B, respectively. An example MCNP6 input file is provided in Attachment C.

Table 2-2. Dosimeter locations. 

Dosimeter location Description

Center chest The lower edge of the dosimeter location approximates the bottom of the 

phantom sternum.

Left collar The upper edge of the dosimeter location approximates the top of the left clavicle.

Center waist The dosimeter location is centered at the approximate location of the belt buckle.

Left chest pocket The upper edge of the dosimeter approximates the location of the top edge of the 

left chest pocket of a laboratory coat.

2.3 CALCULATIONS

Two types of tallies were collected for these calculations. The first type, called an f4 tally, provides a 

track length estimate of the cell fluence. The second type, an f6 tally, is a track length estimate of cell 

fluence modified by an energy deposition (heating) function. 

Calculations were performed for neutron and photon radiations. 

2.4 BENCHMARK CALCULATIONS

The f6 tallies were used to calculate the doses to eight organs – the brain, heart wall, liver, lung, 

kidney, pancreas, thyroid, and urinary bladder wall – as a means of checking the implementations of 

the voxel phantoms and irradiation geometries. The ICRP-evaluated DCCs for fluence to dose for

these eight organs (ICRP 2010) were visually compared with the corresponding DCCs that were 

calculated using MCNP6.1 for this report.

2.5 IRRADIATION GEOMETRY FACTORS

The dosimeter dose calculations used the f4 type tally that was modified to convert photon fluence 

(cm-2) to Hp(10) in picosievert. For photons, the fluence to Hp(10) DCCs were the product of the 

fluence to air kerma factors in Table A.1 of ICRP Publication 74 (ICRP 1996) and the air kerma to 

Hp(10) factors in Table A.24 of Publication 74 (ICRP 1996). The Hp(10) picosievert values were 

collected in 1-keV energy intervals. For neutrons, the fluence to Hp(10) DCCs were those published 

in Table A.42 of Publication 74 (ICRP 1996).

The IGFs in this report are the quotient of the Hp(10) for AP irradiations divided by the Hp(10) for the 

ROT or ISO irradiation geometry, as appropriate.
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3.0 RESULTS

3.1 BENCHMARK CALCULATIONS

Pointwise estimates of the relative difference between the ICRP-evaluated (2010) conversion 

coefficients for fluence to dose and those calculated for this report are shown in Attachment D. 

Visually, the DCCs calculated for this report appear to agree well with the ICRP (2010) DCCs. In 

particular, the plots of the ISO geometry appear to show overall agreements that are similar to the

agreements shown for the AP and ROT irradiation geometries.

3.2 IRRADIATION GEOMETRY FACTORS 

A dosimeter placed in any of the four locations described in this report will underestimate the Hp(10)

to a worker who is actually being irradiated in a ROT or ISO geometry if the dosimeter was calibrated 

for an AP irradiation. This is because the dosimeter is shielded to varying degrees by the body during 

both ROT and ISO geometry irradiation.

The IGFs are based solely on the incident energy of the particle. The IGFs in this report are the 

quotient of the particle fluence in the dosimeter cell for AP irradiations divided by the particle fluence 

in the dosimeter cell for the ROT or ISO irradiation geometry, as appropriate. Because the Hp(10)

and exposure values are the products of the fluence and appropriate conversion factors (ICRP 1987), 

IGFs based on the fluence are applicable for both Hp(10) and exposure calculations.

3.2.1 PHOTON IRRADIATIONS

Pointwise estimates of the IGFs for photons are shown in Figures 3-1 through 3-4. In the figures, the 

dotted vertical lines show the boundaries of the Interactive RadioEpidemiological Program (IREP) 

dose groupings.

The IGF factors for photons that irradiated the voxel phantoms in the ROT irradiation geometry, 

averaged over the IREP energy regions, are listed in Table 3-1. The IGF factors for photons that 

irradiated the voxel phantoms in the ISO irradiation geometry, averaged over the IREP energy 

regions, are listed in Table 3-2. 
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Figure 3-1. IGFs for uncollided photons in dosimeter 

regions when the adult female voxel phantom is irradiated 

in the ROT geometry by monoenergetic photons. 

Figure 3-2. IGFs for uncollided photons in dosimeter 

regions when the adult female voxel phantom is irradiated 

in the ISO geometry by monoenergetic photons. 
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Figure 3-3. IGFs for uncollided photons in dosimeter 

regions when the adult male voxel phantom is irradiated in 

the ROT geometry by monoenergetic photons. 

Figure 3-4. IGFs for uncollided photons in dosimeter 

regions when the adult male voxel phantom is irradiated in 

the ISO geometry by monoenergetic photons. 
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Table 3-1. Estimated ROT IGFs for monoenergetic photons incident on a voxel 

phantom.

Dosimeter position

Energy regions and

estimated IGFs for Hp(10), 

adult female phantom

Energy regions and

estimated IGFs for Hp(10), 

adult male phantom

Center chest ≤30 keV: 2.02

30–250 keV: 1.77

>250 keV: 1.37

≤30 keV: 2.00

30–250 keV: 1.84

>250 keV: 1.44

Left collar ≤30 keV: 1.97

30–250 keV: 1.79

>250 keV: 1.40

≤30 keV: 1.86

30–250 keV: 1.75

>250 keV: 1.40

Center waist ≤30 keV: 1.78

30–250 keV: 1.65

>250 keV: 1.35

≤30 keV: 1.82

30–250 keV: 1.71

>250 keV: 1.40

Left chest pocket ≤30 keV: 1.56

30–250 keV: 1.49

>250 keV: 1.27

≤30 keV: 1.65

30–250 keV: 1.57

>250 keV: 1.33

Average of four 

dosimeter locations

≤30 keV: 1.83

30–250 keV: 1.68

>250 keV: 1.35

≤30 keV: 1.83

30–250 keV: 1.72

>250 keV: 1.39

Table 3-2. Estimated ISO IGFs for monoenergetic photons incident on a voxel 

phantom.

Dosimeter position

Energy regions and

estimated IGFs for Hp(10), 

adult female phantom

Energy regions and

estimated IGFs for Hp(10), 

adult male phantom

Center chest ≤30 keV: 1.96

30–250 keV: 1.76 

>250 keV: 1.42

≤30 keV: 2.00

30–250 keV: 1.85

>250 keV: 1.54

Left collar ≤30 keV: 2.18

30–250 keV: 1.91

>250 keV: 1.46

≤30 keV: 2.07

30–250 keV: 1.87

>250 keV: 1.53

Center waist ≤30 keV: 1.82

30–250 keV: 1.71

>250 keV: 1.43

≤30 keV: 1.88

30–250 keV: 1.77

>250 keV: 1.53

Left chest pocket ≤30 keV: 1.57

30–250 keV: 1.48

>250 keV: 1.28

≤30 keV: 1.63

30–250 keV: 1.55

>250 keV: 1.40

Average of four 

dosimeter locations

≤30 keV: 1.88

30–250 keV: 1.71

>250 keV: 1.40

≤30 keV: 1.90

30–250 keV: 1.76

>250 keV: 1.50

3.2.2 NEUTRON IRRADIATIONS

Pointwise estimates of the IGFs for neutrons are shown in Figures 3-5 through 3-8. In the figures, the 

dotted vertical lines show the boundaries of the IREP dose groupings.

The IGF factors for neutrons that irradiated the voxel phantoms in the ROT irradiation geometry, 

averaged over the IREP energy regions, are listed in Table 3-3. The IGF factors for photons that 

irradiated the voxel phantoms in the ISO irradiation geometry, averaged over the IREP energy 

regions, are listed in Table 3-4. 
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Figure 3-5. IGFs for uncollided neutrons in dosimeter 

regions when the adult female voxel phantom is irradiated 

in the ROT geometry by monoenergetic neutrons. 

Figure 3-6. IGFs for uncollided neutrons in dosimeter 

regions when the adult female voxel phantom is irradiated 

in the ISO geometry by monoenergetic neutrons. 
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Figure 3-7. IGFs for uncollided neutrons in dosimeter 

regions when the adult male voxel phantom is irradiated in 

the ROT geometry by monoenergetic neutrons. 

Figure 3-8. IGFs for uncollided neutrons in dosimeter 

regions when the adult male voxel phantom is irradiated in 

the ISO geometry by monoenergetic neutrons. 
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Table 3-3. Estimated ROT IGFs for monoenergetic neutrons incident on a voxel 

phantom.

Dosimeter position

Energy regions and

estimated IGFs for Hp(10),

adult female phantom

Energy regions and

estimated IGFs for Hp(10),

adult male phantom

Center chest ≤10 keV: 1.68

10–100 keV: 2.02

100 keV–2 MeV: 2.04

2–20 MeV: 2.11

≤10 keV: 1.74

10–100 keV: 2.00

100 keV–2 MeV: 2.02

2–20 MeV: 2.05

Left collar ≤10 keV: 1.68

10–100 keV: 1.97

100 keV–2 MeV: 1.99

2–20 MeV: 2.03

≤10 keV: 1.64

10–100 keV: 1.86

100 keV–2 MeV: 1.86

2–20 MeV: 1.90

Center waist ≤10 keV: 1.58

10–100 keV: 1.77

100 keV–2 MeV: 1.79

2–20 MeV: 1.84

≤10 keV: 1.64

10–100 keV: 1.82

100 keV–2 MeV: 1.84

2–20 MeV: 1.88

Left chest pocket ≤10 keV: 1.43

10–100 keV: 1.57

100 keV–2 MeV: 1.58

2–20 MeV: 1.60

≤10 keV: 1.51

10–100 keV: 1.65

100 keV–2 MeV: 1.66

2–20 MeV: 1.69

Average of four 

dosimeter locations

≤10 keV: 1.59

10–100 keV: 1.83

100 keV–2 MeV: 1.85

2–20 MeV: 1.89

≤10 keV: 1.63

10–100 keV: 1.83

100 keV–2 MeV: 1.84

2–20 MeV: 1.88

Table 3-4. Estimated ISO IGFs for monoenergetic neutrons incident on a voxel 

phantom.

Dosimeter position

Energy regions and

estimated IGFs for Hp(10),

adult female phantom

Energy regions and

estimated IGFs for Hp(10),

adult male phantom

Center chest ≤10 keV: 1.69

10–100 keV: 1.95

100 keV–2 MeV: 1.98

2–20 MeV: 2.05

≤10 keV: 1.77

10–100 keV: 2.01 

100 keV–2 MeV: 2.02 

2–20 MeV: 2.07

Left collar ≤10 keV: 1.80

10–100 keV: 2.17

100 keV–2 MeV: 2.21

2–20 MeV: 2.28

≤10 keV: 1.77

10–100 keV: 2.06

100 keV–2 MeV: 2.08

2–20 MeV: 2.15

Center waist ≤10 keV: 1.65

10–100 keV: 1.81

100 keV–2 MeV: 1.82

2–20 MeV: 1.88

≤10 keV: 1.72

10–100 keV: 1.88

100 keV–2 MeV: 1.89

2–20 MeV: 1.94

Left chest pocket ≤10 keV: 1.43

10–100 keV: 1.56

100 keV–2 MeV: 1.57

2–20 MeV: 1.60

≤10 keV: 1.50

10–100 keV: 1.62

100 keV–2 MeV: 1.63

2–20 MeV: 1.67

Average of four 

dosimeter locations

≤10 keV: 1.64

10–100 keV: 1.87

100 keV–2 MeV: 1.90

2–20 MeV: 1.95

≤10 keV: 1.69

10–100 keV: 1.89

100 keV–2 MeV: 1.90

2–20 MeV: 1.96

3.3 ANGULAR RESPONSE

The data above show that the IGFs for the left chest pocket are always low. The reason for this is the 

location of the dosimeter to the left side of the phantom. Figure 3-9 shows the particle fluence (in 
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 17 of 63

 

arbitrary units) from 200-keV photons at the four dosimeter locations as the radiation source rotates 

around the adult male phantom. The angles are measured from the Cartesian y-axis so the source at 

0 degrees gives an AP irradiation geometry. The angular response of the three dosimeters located 

on, or near, the centerline of the phantom, center chest, center waist, and left collar are shown. As 

would be expected, there is a steep decline in the calculated photon fluence when the incident 

photons are started from a region behind the phantom (angles between π/2 and 3π/2 radians). The 

left chest pocket dosimeter is offset to the left (see Figures A-8 and B-2), which results in it being 

irradiated to a greater extent than for the other three dosimeter locations at angles between 90 and 

135 degrees (π/2 and 3π/4 radians) as can be seen in Figure 3-9. The enhanced irradiation of the left 

chest pocket dosimeter is the reason that the IGFs of the left chest dosimeter location are lower than 

those for the other three dosimeter locations. 

The data in Figure 3-9 show that the assumption of an AP irradiation geometry provides the correct 

fluence even if the rotational angle deviates from the AP irradiation geometry by up to ±75 degrees 

(±5/6π radians). The data also show that, except for the left chest pocket dosimeter location at the 

incident angles mentioned above, the particle fluence at the dosimeter location does not vary greatly 

with dosimeter location.

Figure 3-9. Rotational dependence of fluence at four 

dosimeter locations for uncollided 0.2-MeV photons.

4.0 DISCUSSION

These preliminary factors indicate that, within the selected energy bins, the male and female IGFs are 

nearly equal. The factors also show that they vary according to the location of the dosimeter but that 

the dependence is not large, except for the left chest pocket location, and that an IGF based on the 

center chest location will tend to be favorable to claimants. 

The factors described above do not account for the angular response of the dosimeter that might be 

worn by the worker but only represents the radiation that is available to the dosimeter. The factors 

also do not account for the efficiencies of any particular dosimeter and, in particular, do not account 
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 18 of 63

 

for the response of the dosimeter to albedo radiation. The albedo and angular response of site 

dosimeters should be considered when documenting the appropriate IGFs in the technical basis 

documents and dose reconstruction tools and methods, which should provide appropriate direction. 

5.0 SUMMARY

IGFs that account for the reduction in apparent particle fluence to which dosimeters are exposed in 

the ROT and ISO geometries were calculated. The factors vary according to dosimeter location on 

the body and the energy of the particles that irradiate the body. The factors for male and female 

phantoms are similar. The factors tend to decrease as the particle energy increases. A dosimeter 

placed on the center chest tends to result in the largest (most favorable to claimants) DCC. 
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 19 of 63

 

REFERENCES

González, Á., 2009, “Measurement of Areas on a Sphere Using Fibonacci and Latitude–Longitude

Lattices,” Mathematical Geosciences, volume 42, pp. 49–64. [SRDB Ref ID: 154005]

Hannay, J. H., and J. F. Nye, 2004, “Fibonacci Numerical Integration on a Sphere,” Journal of Physics

A: Mathematical and General, volume 37, number 48, pp. 11591–11601. [SRDB Ref ID: 

154003]

ICRP (International Commission on Radiological Protection), 1987, Data for Use in Protection Against 

External Radiation, Publication 51, Pergamon Press, Oxford, England. [SRDB Ref ID: 

135826]

ICRP (International Commission on Radiological Protection), 1996, Conversion Coefficients for Use in 

Radiological Protection Against External Radiation, Publication 74, Pergamon Press, Oxford, 

England. [SRDB Ref ID: 7979]

ICRP (International Commission on Radiological Protection), 2009, Adult Reference Computational 

Phantoms, Publication 110, Pergamon Press, Oxford, England. 

ICRP (International Commission on Radiological Protection), 2010, Conversion Coefficients for 

Radiological Protection Quantities for External Radiation Exposures, Publication 116, Elsevier 

Press, Philadelphia, Pennsylvania.

LANL (Los Alamos National Laboratory), 2011, “Interpreted ENDF File for ENDFB-VII.1-neutron/O/16” 

downloaded from the T-2 Nuclear Information Service http://t2.lanl.gov/nis/data/data/ENDFBVII.1-neutron/O/16 on 8-Feb-2016. Los Alamos National Security, Los Alamos, New Mexico. 

[SRDB Ref ID: 154073] 

NIOSH (National Institute for Occupational Safety and Health), 2007, External Dose Reconstruction 

Implementation Guideline, OCAS-IG-001, Rev. 3, Office of Compensation Analysis and 

Support, Cincinnati, Ohio, November 21.

Pelowitz, D. B., editor, 2013, MCNP6TM User’s Manual, Version 1.0, LA-CP-13-00634, Rev. 0., Los 

Alamos National Laboratory, Los Alamos, New Mexico. 

RDCT (R Development Core Team), 2014, R: A Language and Environment for Statistical Computing, 

Reference Index, R Foundation for Statistical Computing, Vienna, Austria, April 14.

SC&A (Sanford Cohen & Associates), 2005, The Review of NIOSH/ORAUT Procedures and Methods 

Used for Dose Reconstruction, SCA-TR-Task3, Rev. 0, McLean, Virginia, January 17. [SRDB 

Ref ID: 137643]

Swinbank, R., and R. J. Purser, 2006, “Fibonacci Grids: A Novel Approach to Global Modeling,”

Quarterly Journal of the Royal Meteorological Society, volume 132, number 619, pp. 1769–

1793. [SRDB Ref ID: 154072] 

Thierry-Chef, I., F. Pernicka, M. Marshall, E. Cardis, and P. Andreo, 2002, “Study of a Selection of 

10 Historical Types of Dosemeter: Variation of the Response to Hp(10) with Photon Energy 

and Geometry of Exposure,” Radiation Protection Dosimetry, volume 102, number 2, pp. 101–

113. [SRDB Ref ID: 11296]
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ATTACHMENT A 

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM

LIST OF FIGURES

FIGURES TITLE PAGE

A-1 Elevation view of the adult female voxel phantom showing the center chest dosimeter 

location ..................................................................................................................................21

A-2 Plan view of the adult female voxel phantom showing the center chest dosimeter 

location ..................................................................................................................................22

A-3 Elevation view of the adult female voxel phantom showing the left collar dosimeter 

location ..................................................................................................................................22

A-4 Plan view of the adult female voxel phantom showing the left collar dosimeter location ......... 23

A-5 Elevation view of the adult female voxel phantom showing the center waist dosimeter 

location ..................................................................................................................................23

A-6 Plan view of the adult female voxel phantom showing the center waist dosimeter location .... 24

A-7 Elevation view of the adult female voxel phantom showing the left chest pocket 

dosimeter location..................................................................................................................25

A-8 Plan view of the adult female voxel phantom showing the left chest pocket dosimeter 

location ..................................................................................................................................26
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ATTACHMENT A

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM (continued)

The locations of the dosimeters on the adult female voxel phantom are shown in this attachment. The 

dosimeters are the clear areas shown on the phantom, which consists of many voxels. The grid lines 

in the figures are the surface lines of the individual voxels. Shaded voxels are those that contain 

tissue materials; unshaded voxels do not contain any material. The dosimeters shown in the figures 

are also empty as described in Section 2.2 of the report.

Center Chest Dosimeter

Figure A-1. Elevation view of the adult female 

voxel phantom showing the center chest 

dosimeter location.
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ATTACHMENT A

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM (continued) Center Chest Dosimeter

Figure A-2. Plan view of the adult female voxel phantom showing the 

center chest dosimeter location.

Left Collar Dosimeter

Figure A-3. Elevation view of the adult female voxel 

phantom showing the left collar dosimeter location. 
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 23 of 63

ATTACHMENT A

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM (continued) Left Collar Dosimeter

Figure A-4. Plan view of the adult female voxel 

phantom showing the left collar dosimeter location.

Center Waist Dosimeter

Figure A-5. Elevation view of the adult female 

voxel phantom showing the center waist 

dosimeter location.
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 24 of 63

ATTACHMENT A

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM (continued) Center Waist Dosimeter

Figure A-6. Plan view of the adult female voxel phantom showing the center 

waist dosimeter location.
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ATTACHMENT A

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM (continued)

Left Chest Pocket Dosimeter

Figure A-7. Elevation view of the adult female 

voxel phantom showing the left chest pocket 

dosimeter location.
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ATTACHMENT A

DOSIMETER LOCATIONS ON THE ADULT FEMALE VOXEL PHANTOM (continued) Left Chest Pocket Dosimeter

Figure A-8. Plan view of the adult female voxel phantom showing the left 

chest pocket dosimeter location. 
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ATTACHMENT B 

DOSIMETER LOCATIONS ON THE ADULT MALE VOXEL PHANTOM

LIST OF FIGURES

FIGURES TITLE PAGE

B-1 Elevation view of the adult male voxel phantom showing the center chest and center 

waist dosimeter locations ....................................................................................................... 28

B-2 Plan view of the adult male voxel phantom showing the center chest and left chest 

pocket dosimeter locations..................................................................................................... 29

B-3 Plan view of the adult male voxel phantom showing the center waist dosimeter location ....... 29

B-4 Plan view of adult male voxel phantom showing the left collar dosimeter............................... 30

B-5 Elevation view of the adult male voxel phantom showing the left collar dosimeter location..... 30

B-6 Elevation view of the adult male voxel phantom showing the left chest pocket dosimeter 

location ..................................................................................................................................31
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ATTACHMENT B 

DOSIMETER LOCATIONS ON THE ADULT MALE VOXEL PHANTOM (continued)

The locations of the dosimeters on the adult male voxel phantom are shown in this attachment. The 

dosimeters are the clear areas shown on the phantom, which consists of many voxels. The grid lines 

in the figures are the surface lines of the individual voxels. Shaded voxels are those that contain 

tissue materials; unshaded voxels do not contain any material. The dosimeters shown in the figures 

are also empty as described in Section 2.2 of the report.

Center Chest Dosimeter

Center Waist Dosimeter

Figure B-1. Elevation view of the adult 

male voxel phantom showing the 

center chest and center waist 

dosimeter locations. 
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ATTACHMENT B 

DOSIMETER LOCATIONS ON THE ADULT MALE VOXEL PHANTOM (continued) Left Chest Pocket Dosimeter Center Chest Dosimeter

Figure B-2. Plan view of the adult male voxel phantom showing the center 

chest and left chest pocket dosimeter locations. Center Waist Dosimeter

Figure B-3. Plan view of the adult male voxel phantom showing the center 

waist dosimeter location.
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 30 of 63

ATTACHMENT B 

DOSIMETER LOCATIONS ON THE ADULT MALE VOXEL PHANTOM (continued) Left Collar Dosimeter

Figure B-4. Plan view of adult male voxel phantom showing the left collar 

dosimeter.

Left Collar Dosimeter

Figure B-5. Elevation view of the adult male voxel phantom 

showing the left collar dosimeter location.
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ATTACHMENT B 

DOSIMETER LOCATIONS ON THE ADULT MALE VOXEL PHANTOM (continued)

Figure B-6. Elevation view of the adult male voxel phantom 

showing the left chest pocket dosimeter location.

Chest Pocket Dosimeter
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 32 of 63

ATTACHMENT C 

EXAMPLE MCNP6 INPUT FILE

This attachment contains one example of the MCNP6.1 input files that were used for this report. The 

example input file is for an adult male phantom irradiated by an aligned and expanded beam of 

0.3-MeV neutrons at discrete angles that range from 0 to 355 degrees in 5-degree increments. The 

input file implements the ROT irradiation geometry. The “fill” card has been edited to remove 

29,277 lines of the original file.
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 33 of 63

ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
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ATTACHMENT C

EXAMPLE MCNP6 INPUT FILE (continued)
Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 54 of 63

ATTACHMENT D 

RESULTS OF REFERENCE CALCULATIONS

LIST OF FIGURES

FIGURES TITLE PAGE

D-1 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic neutrons, AP geometry ................................. 57

D-2 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic neutrons, AP geometry .................................... 57

D-3 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic neutrons, ROT geometry............................... 58

D-4 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic neutrons, ROT geometry.................................. 58

D-5 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic neutrons, ISO geometry ................................ 59

D-6 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic neutrons, ISO geometry................................... 59

D-7 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic photons, AP geometry................................... 60

D-8 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic photons, AP geometry ..................................... 60

D-9 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic photons, ROT geometry................................ 61

D-10 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic photons, ROT geometry................................... 61

D-11 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult female reference organs, monoenergetic photons, ISO geometry ................................. 62

D-12 Relative differences between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, 

adult male reference organs, monoenergetic photons, ISO geometry .................................... 62

D-13 Comparison between ICRP-evaluated DCCs and ORAU Team-calculated DCCs, adult 

female and male urinary bladder wall, monoenergetic neutrons, AP geometry....................... 63
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ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

Figures D-1 to D-13 show the results of the benchmarking calculations that were described in 

Sections 2.4 and 3.1. The figures compare the organ DCCs calculated with MCNP6.1 for this report 

to those in ICRP Publication 116 (ICRP 2010). The figures show the relative difference between the 

two sets of dose calculations. The figures show the results for irradiation of the adult male and adult 

female voxel phantoms by neutrons and photons in the AP, ROT, and ISO irradiation geometries.

The absorbed DCCs that were calculated for benchmarking were obtained by applying a cubic spline 

smoothing function to the calculated data to obtain a smooth curve of the DCCs as a function of 

neutron or photon energy, as applicable. In similarity to ICRP, the DCCs at specified energy points 

were evaluated using the smoothed data curve. 

For the MCNP6.1 calculated data, the R (R Core Team 2014) function “smooth.spline” was used to 

compute the cubic spline object from log-log transformed data and the function “predict.smooth.spline” 

was used to evaluate the fitted data. The energy-specific DCCs calculated for this report were 

compared with the evaluated DCCs calculated by ICRP (2010).

The figures in this attachment provide a subjective view of how well the DCCs calculated for the 

benchmarking organs agree with the DCCs in ICRP Publication 116 (ICRP 2010). In all figures, the 

notation “ICRP” refers to the DCCs tabulated in Publication 116, and the notation “ORAUT” refers to 

the DCCs calculated for this report. The good agreement between the ICRP DCCs and the ORAUT 

DCCs indicates that the ORAUT implementations of the ICRP voxel phantoms and the irradiation 

geometries are correct.

Figures D-1 through D-12 show the pointwise relative difference between the ICRP and ORAUT 

DCCs for all eight reference organs. The relative difference, RD, between ICRP and ORAUT 

absorbed DCCs was calculated using Equation D-1:

( − ) = ORAUT ICRP

ICRP

DCC DCC RD

DCC D-1 

Where DCCICRP is the particle and energy-specific DCC calculated by the ICRP and DCCORAUT is the 

corresponding particle and energy-specific DCC calculated for this report.

Figures D-1 through D-6 show the results for incident neutrons while Figures D-7 through D-12 show 

the results for incident photons.

Referring to Figures D-1 through D-6, the ORAUT DCCs appear to be biased high for 20 MeV incident 

neutrons. This apparent bias is caused by how the cubic spline smoother calculates smoothed data 

at the endpoints of the data. The ORAUT data terminate at 20 MeV while the ICRP data continue on 

to 10 GeV and are thus more constrained than are the ORAUT data.

Referring to Figures D-1, D-3 and D-5, the ORAUT DCCs appear to be biased high in the 0.005 to 

0.03 MeV neutron energy region. Figure D-13 compares the ORAUT and ICRP DCCs for the urinary 

bladder wall, the organ that shows maximal bias of the ORAUT calculations, for both the female and 

male phantoms. This figure shows that the the ORAUT and ICRP DCCs for the adult male phantom 

agree well at all energies but that for the adult female phantom, in the energy region defined above, 

there is divergence between the ORAUT and ICRP DCCs. Although not shown here, additional plots, 

similar to Fig D-13 and plots of the total neutron cross section for urinary bladder wall tissue, which is 

identical for the female and male phantoms, indicate that the ICRP DCCs are slightly smaller than the 
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ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

ORAUT DCCs and the difference occurs in the region of the total neutron cross section plot where the 

cross section rolls-off from a level region. The cause of the bias has not been determined but has 

been noted, investigated, and is evaluated to be small and does not appear to be due to errors in 

modeling. The cause of the apparent bias will be investigated when it becomes important to calculate 

radiation doses to organs.

Referring to Figure D-13, a vertical line denotes the DCCs that are calculated when the phantoms are

irradiated by 1-MeV neutrons. The plotting symbol shows the DCC calculated using MCNP6.1, while 

the solid line shows the smoothed data. A similar deviation at 1 MeV is seen in Publication 116 

Annex I for the ICRP calculations (ICRP 2010). The deviation is a reduction in the DCC due to a 

resonance peak in the neutron cross section of 16O at 1 MeV (LANL 2011) and the removal of that 

effect by the cubic spline smoothers that were used by the ICRP and for this report. 

The upper photon energy for the photon plots is 3 MeV. This energy was chosen because the 

MCNP6.1 tally used for estimating the benchmark DCCs was the “f6:p“ tally, which is a track length 

estimator of kerma rather than absorbed dose. The kerma and absorbed dose DCCs diverge at 3 

MeV.
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

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Figure D-1. Relative differences between ICRP-evaluated DCCs 

and ORAU Team-calculated DCCs, adult female reference 

organs, monoenergetic neutrons, AP geometry. 

1e-08 1e-06 1e-04 1e-02 1e+00

-0.10 -0.05 0.00 0.05 0.10

Neutron Energy (MeV)

Relative Difference: ORAUTspline vs ICRP

Adult Male, AP Geometry, Relative 

Brain

Thyroid

Lung

Kidney

HtWall

Liver

Pancreas

UBwall

Figure D-2. Relative differences between ICRP-evaluated DCCs

and ORAU Team-calculated DCCs, adult male reference organs, 

monoenergetic neutrons, AP geometry. 
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

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Figure D-3. Relative differences between ICRP-evaluated

DCCsand ORAU Team-calculated DCCs, adult female reference 

organs, monoenergetic neutrons, ROT geometry.

1e-08 1e-06 1e-04 1e-02 1e+00

-0.10 -0.05 0.00 0.05 0.10

Neutron Energy (MeV)

Relative Difference: ORAUTspline vs ICRP

Adult Male, ROT Geometry, Relati 

Brain

Thyroid

Lung

Kidney

HtWall

Liver

Pancreas

UBwall

Figure D-4. Relative differences between ICRP-evaluated DCCs

and ORAU Team-calculated DCCs, adult male reference organs, 

monoenergetic neutrons, ROT geometry. 
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

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Figure D-5. Relative differences between ICRP-evaluated DCCs 

and ORAU Team-calculated DCCs, adult female reference 

organs, monoenergetic neutrons, ISO geometry. 

1e-08 1e-06 1e-04 1e-02 1e+00

-0.10 -0.05 0.00 0.05 0.10

Neutron Energy (MeV)

Relative Difference: ORAUTspline vs ICRP

Adult Male, ISO Geometry, Relativ 

Brain

Thyroid

Lung

Kidney

HtWall

Liver

Pancreas

UBwall

Figure D-6. Relative differences between ICRP-evaluated DCCs

and ORAU Team-calculated DCCs, adult male reference organs, 

monoenergetic neutrons, ISO geometry. 
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

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Figure D-7. Relative differences between ICRP-evaluated DCCs

and ORAU Team-calculated DCCs, adult female reference 

organs, monoenergetic photons, AP geometry. 

Figure D-8. Relative differences between ICRP-evaluated DCCs

and ORAU Team-calculated DCCs, adult male reference organs, 

monoenergetic photons, AP geometry. 
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

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Figure D-9. Relative differences between ICRP-evaluated DCCs

and ORAU Team-calculated DCCs, adult female reference 

organs, monoenergetic photons, ROT geometry. 

Figure D-10. Relative differences between ICRP-evaluated

DCCs and ORAU Team-calculated DCCs, adult male reference 

organs, monoenergetic photons, ROT geometry. 
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

Document No. ORAUT-RPRT-0068 Revision No. 0

0 Effective Date: 07/11/2016 Page 62 of 63

Figure D-11. Relative differences between ICRP-evaluated

DCCs and ORAU Team-calculated DCCs, adult female reference 

organs, monoenergetic photons, ISO geometry. 

Figure D-12. Relative differences between ICRP-evaluated

DCCs and ORAU Team-calculated DCCs, adult male reference 

organs, monoenergetic photons, ISO geometry. 
ATTACHMENT D

RESULTS OF REFERENCE CALCULATIONS (continued)

Document No. ORAUT-RPRT-0068 Revision No. 00 Effective Date: 07/11/2016 Page 63 of 63

1e-08 1e-06 1e-04 1e-02 1e+00

2 5 10 20 50

Neutron Energy (MeV)

Dose Factor (pGy cm^2)

AP Geometry, UBwall

Male

ORAUT

ICRP

Female

ORAUT

ICRP

1 MeV

Figure D

-13. Comparison between ICRP-evaluated DCCs and

ORAU Team-calculated DCCs, adult female and male urinary

bladder wall, monoenergetic neutrons, AP geometry.