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ED03- Skin Dose from External Sources

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DEFENSE THREAT REDUCTION AGENCY

NUCLEAR TEST PERSONNEL REVIEW PROGRAM

RADIATION DOSE ASSESSMENT

STANDARD METHOD

ED03 – Skin Dose from External Sources

Revision 2.0

Cleared for Release

Key to SOP ID Codes

RA (Radiation Assessment - SOP)

ED (External Dose - Standard Methods)

ID (Internal Dose - Standard Methods)

UA (Uncertainty Analysis - Standard Methods)
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Revision Control

Revision Revision Description Revision 

Date

Authorization 

Official

1.0 Original 10/31/2007 Paul K. Blake

1.2 - New version. Revision 1.0 (considered a working draft) was 

completely rewritten to produce Rev. 1.2. 

- No Rev. 1.1 of this SM was produced.

10/31/2008 Paul K. Blake

1.3 - Minor editorial changes 01/31/2010 Paul K. Blake

2.0 - Explained the use of beta-gamma dose ratios for occupation troops at 

Hiroshima and Nagasaki in Section 5.2.1.2.

-Updated the beta-gamma dose ratios for neutron-activated soil in 

Section 5.2.1.2

- Updated the immersion dose equations in Section 5.3

- Added “hand” as an anatomical location in Table 8

- Updated several references in Section 8 (References) 

- Made editorial changes and minor corrections as needed throughout 

document

04/30/2021 James D. Franks
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Table of Contents

Table of Contents............................................................................................................................ 3

List of Figures................................................................................................................................. 4

List of Tables .................................................................................................................................. 4

1. Purpose/Summary............................................................................................................... 5

2. Scope................................................................................................................................... 5

3. Responsibilities................................................................................................................... 5

4. Definitions........................................................................................................................... 5

5. Method Description ............................................................................................................ 6

5.1 Gamma Radiation Skin Dose.................................................................................. 7

5.2 Beta Radiation Skin Dose ....................................................................................... 7

5.2.1 Infinite Plane Source................................................................................... 9

5.2.2 Finite Plane Source ................................................................................... 19

5.2.3 Point Source .............................................................................................. 26

5.3 Volumetric Source: Skin Dose from Swimming in Contaminated Water............ 27

5.4 Uncertainty Analysis............................................................................................. 28

6. Data and Input................................................................................................................... 28

7. Referenced SOPs and Standard Methods from this Manual............................................. 29

8. References......................................................................................................................... 29

Normalized Doses for Finite Circular Sources ..................................................... 31

Attachment 2. Small Boat Information......................................................................................... 51
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List of Figures

Figure 1. Cross Section of Skin (WebMD, 2019).......................................................................... 8

Figure 2. Location of Basal Cell Layer (ICRU, 1997) .................................................................. 8

Figure 3. SSMF as Function of Source Radius for Various Times after Detonation................... 25

List of Tables

Table 1. Beta-to-Gamma Dose Ratios for Bare Skin Exposures to Mixed Fission Products at 

Pacific Proving Ground............................................................................................... 10

Table 2. Beta-to-Gamma Dose Ratios for Bare Skin Exposures to Mixed Fission Products at the 

Nevada Test Site ......................................................................................................... 10

Table 3. Beta-to-Gamma Dose Ratios for Bare Skin Exposures to Mixed Fission Products and 

Actinides at Pacific Test Sites..................................................................................... 11

Table 4. Beta-to-Gamma Dose Ratios for Bare Skin Exposures to Neutron-Activated Soil at 

NTS for Very Short Stay Times (Δt → 0) .................................................................. 13

Table 5. Modification Factor for Light Clothing for Exposures to Mixed Fission Products....... 14

Table 6. Beta-to-Gamma Dose Ratios for Heel of Foot inside a Boot ........................................ 14

Table 7. Coefficients to Calculate Beta-to-Gamma Dose Ratios ................................................ 15

Table 8. Reference Distances above a Plane for Various Anatomical Locations........................ 19

Table 9. Beta-to-Gamma Emission Rate Ratios N(t) at Selected Times after Detonation. ...... 21

Table 10. SSMF for Specific Naval Vessels................................................................................ 25
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Standard Method

ED03 – Skin Dose from External Sources 

1. Purpose/Summary

Standard Method (SM) ED03, Skin Dose from External Sources, provides general 

technical methods for assessing dose to the skin from surface-deposited fallout and 

activated sources to individuals in the Nuclear Test Personnel Review (NTPR) Program 

according to the procedures specified in SOP RA01. The skin dose from dermal 

contamination is addressed in SM ED04, Skin Dose from Dermal Contamination.

2. Scope

This standard method provides technical guidance for reconstructing skin doses due to 

beta particle and gamma-ray ionizing radiation from exposure to surface-deposited fallout 

and activated sources. This standard method should not be used to determine skin doses 

due to alpha radiation, internally deposited radioactive material exposures, or as the sole 

method for determining external radiation exposures (including skin contamination). This 

standard method is used in conjunction with other standard methods for assessing whole 

body radiation exposures in accordance with the requirements of Title 32, Code of 

Federal Regulations, Part 218, “Guidance for the Determination and Reporting of 

Nuclear Radiation Dose for DoD Participants in the Atmospheric Nuclear Test

Program” (DoD, 2020). 

3. Responsibilities 

Qualified radiation dose analysis staff members use these methods and associated tools 

for assessing the radiation doses for exposed individuals. It is the responsibility of the 

analysts to understand and correctly apply the methods and techniques presented below. 

If situations arise where these methods and techniques are inadequate to address a 

specific exposure scenario, it is the responsibility of the analyst encountering this 

deficiency to bring it to the attention of appropriate staff personnel so that the 

methodology can be extended as required to provide adequate estimates of skin doses 

from external sources. It is the responsibility of the staff member executing and 

implementing this extension to document such in a revision to this standard method.

4. Definitions

Acute Exposure: Exposure to radiation from less than one to several hours, exemplified 

by a typical time period of a day’s activity at a test site.

Beta Radiation: Electrons emitted in nuclear decay processes.
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Beta-to-Gamma Dose Ratio: The ratio of skin dose from beta radiation to film badge (or 

film badge-equivalent) gamma dose.

Chronic Exposure: Exposure to radiation on a continuing basis over a time period greater 

than 1 day. 

Film Badge: A device, frequently issued and worn during nuclear weapons testing, that 

records external gamma dose. A “properly worn” film badge is one that is assumed to be 

affixed to the external surface of clothing at a height of 137 cm on a standing individual.

Film Badge-Equivalent Dose: The reconstructed gamma dose that would have been 

recorded on a properly worn film badge.

Finite Plane Source: Fallout uniformly deposited over an area smaller than that used to 

define an infinite plane source constitutes a finite plane source. Shrinking a finite source 

to an infinitesimal diameter constitutes point source geometry.

Individual: Any member of the Armed Forces who participated in the atmospheric 

nuclear weapons testing program.

Infinite Plane Source: Fallout uniformly deposited over a flat surface constitutes an 

infinite plane source if the lateral dimensions of the contaminated surface are large 

compared to the mean free path (mfp) of the emitted gamma rays. (The field size criterion 

is referenced to gamma ray mfp because gammas propagate much farther in air than do 

beta particles/electrons.) Such a surface is generally represented by land (e.g., Pacific 

islands and Nevada Test Site) where the radiation can originate 200 m or more in all 

directions from an individual standing on the ground.

Source Size Modification Factor (SSMF): A parameter that corrects the infinite geometry 

beta-to-gamma dose ratio for finite geometry applications. Without such correction, beta 

dose may be significantly underestimated when applying infinite-geometry ratios to 

finite-geometry exposures. 

5. Method Description

Surface-deposited fallout and neutron-activated materials provided sources for skin 

exposure of external origin. Individuals present during the nuclear weapons testing were 

potentially exposed to initial gamma and neutron emissions from the detonation, and to 

gamma and beta emissions from mixed fission products and actinides in fallout and from 

neutron activation products in the soil and surrounding environment. Monitoring devices 

(film badges) were worn by individuals, or by representative members of groups of 

individuals, during most weapon testing activities. These film badges measured the 

amount of gamma radiation individuals received during testing activities. If a specific 

individual did not wear a film badge, it is generally possible to reconstruct the 

individual’s gamma dose based upon film badges worn by other individuals in the nearby 

vicinity or from gamma intensity measurements. Utilizing film badge data or gamma 

dose reconstruction, it is also possible to estimate the dose the individual received due to 

beta radiation from the surrounding environment (fallout and soil).
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5.1 Gamma Radiation Skin Dose

Given the nature of gamma interaction with human tissue, skin dose due to gamma 

radiation is assumed to equal the film badge or reconstructed film badge-equivalent dose. 

5.2 Beta Radiation Skin Dose

Beta radiation can have sufficient energy to penetrate the epidermal skin layer. Thus, beta 

radiation can be considered an external radiation source contributing to skin dose along 

with gamma radiation (Turner, 1995). Beta skin dose from external sources is accrued 

concurrently with the gamma dose from mixed fission products, actinides and neutronactivated material. For an infinite plane source, the relationship between the beta dose 

and the gamma dose can be expressed by a beta-to-gamma dose ratio. This ratio is 

dependent on time (because the spectrum of the emitted radiation changes with time) and 

on the geometrical relationship between an individual and the source (e.g., distance from 

or height above the source) (Barss and Weitz, 2006).

Due to beta particle range and attenuation characteristics, beta dose depends more 

critically than gamma dose on geometry and the shielding material between the radiation 

source and the individual. Thus, the nature of specific jobs or task-related activities and 

their associated protective measures must be considered when reconstructing beta skin 

dose (Barss and Weitz, 2006).

Understanding radiation injury of the skin is enhanced by a basic understanding of the 

anatomy of the organ. Skin consists of a keratinized stratified squamous cell tissue 

termed the epidermis, a juxtaposed supporting dermis of connective tissue fibers, nerves 

and vessels, and a deeper supporting fat pad, the hypodermis, shown in Figure 1. Beta 

doses to the skin are evaluated at the anatomic location where a skin cancer has been 

diagnosed. The skin dose estimation methodology considers the basal cell layer between 

the epidermis and the dermis, shown in Figure 2, to be the target organ for the induction 

of skin cancer (ICRU, 1997). Although the depth of the basal cell layer can vary from 20 

to 100 μm (ICRU, 1997), the depth for the evaluation is generally taken as 70 μm. This 

depth is consistent with ICRP (2002) and ICRU (1997) as the reference epidermal 

thickness. Basal cells consist of a single layer of cells and, as they divide, produce

upward migrating cells that eventually become the keratinized outer layer of skin, the 

horny layer or stratum corneum. Keratin is the component of nails, hair and the dry outer 

layer of skin that is strong and impermeable to water. The basal cells, comprising the 

stratum basale or stratum germinativum, are very active metabolically and their active 

DNA is very sensitive to ionizing and ultraviolet (UV) radiation, thus the low energy 

threshold for skin injury. 
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Figure 1. Cross Section of Skin (WebMD, 2019)

Figure 2. Location of Basal Cell Layer (ICRU, 1997)

Skin doses from external sources may result from four source configurations: infinite

plane, finite plane, point, and volumetric. Examples of sources that can usually be treated 

as infinite planes are fallout deposited on land and neutron-activated materials in soil. 

Finite plane sources include the fallout-contaminated topside of a ship and contaminated 

equipment, aircraft, and engines. Point sources are isolated “hot spots” whose spatial 

dimension is small compared to the source-target distance; examples include

contaminated tools, encapsulated radioactive sources used for calibration, and cloud 

sampling filters. The most commonly encountered volumetric source is contaminated 

lagoon water. When reconstructing an individual’s skin dose, it will generally be 
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necessary to consider multiple source configurations relevant to the exposure scenario. 

Consider, for example, an individual who served on a contaminated ship during a Pacific 

test series, and was exposed to a finite fallout source when topside on the ship, to an 

infinite fallout source when taking liberty on a contaminated island, and to a volumetric 

source while swimming in contaminated water. 

The internal contamination of a ship’s saltwater system and the contaminants on the 

exterior hull generally did not constitute sources of beta exposure (because of the 

intrinsic shielding of these structures) unless the individual was involved in intrusive 

inspection/maintenance of the saltwater system or was directly exposed to the external 

hull (e.g., while inspecting, scraping, and/or painting it). In addition, it is assumed that no 

beta doses were accrued by individuals while inside buildings or aircraft that were not 

internally contaminated.

5.2.1 Infinite Plane Source

Spectral Characterization of Radiation Emitted from Fallout

Fast fissioning of U-235 is generally representative of the fission process that took place 

during the detonations of nuclear test devices. The gamma and beta emissions from 

fission products produced in such detonations are characterized by their energy spectra 

(Finn et al., 1979). The Finn spectra for the fast fission of U-235, given in the cited 

reference for 32 times from 0 to 70 years post-detonation, were used in the following 

analysis. Although the spectra differ somewhat from device to device, these variations 

usually have little effect on the beta-to-gamma dose ratios and can generally be ignored. 

An exception is the un-fissioned safety shots where isotopes of uranium and plutonium 

are the predominant radionuclides. The impact of actinide content in the fallout, 

potentially significant for thermonuclear detonations, is assessed below.

5.2.1.1 Beta-to-Gamma Dose Ratios for Infinite Geometries

The methods and assumptions for using the Finn spectra to calculate the infinite plane 

source beta-to-gamma dose ratios, R, are presented in Barss and Weitz (2006). These 

ratios apply to bare skin exposure of an individual standing upright in a planar fallout 

field of infinite spatial extent. It was assumed in the derivation that body self-shielding 

(1) reduced the beta dose at any target site on the body by a factor of 0.5 from its 

free-field value, and (2) reduced the gamma dose recorded on a properly worn film badge 

to a value of 0.7 times its free-field value. Tables of R(h,t) as functions of distance (h) 

from the contaminated surface to the target site on an individual’s body and time (t) after 

the detonation are presented below (Barss and Weitz, 2006). Table 1 and Table 2 are 

generally applicable to fission detonations at Pacific Proving Ground (PPG) and the 

Nevada Test Site (NTS), respectively. The values in Table 1 are also used for occupation 

troops at Hiroshima or Nagasaki and for POWs that passed near either ground zero (GZ). 
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Table 1. Beta-to-Gamma Dose Ratios for Bare Skin Exposures

to Mixed Fission Products at Pacific Proving Ground

Time t after 

Detonation

Distance h from source plane (cm)

1 20 40 80 100 120 160 200

0.5 h 36.4 24.2 17.7 11.9 10.4 9.1 7.0 5.4

1 h 32.5 21.4 15.5 10.3 8.9 7.8 5.9 4.5

2 h 32.0 20.8 15.0 9.9 8.5 7.4 5.5 4.2

4 h 40.3 25.9 18.5 12.0 10.3 8.9 6.7 5.0

6 h 51.1 32.6 23.1 14.9 12.7 11.0 8.2 6.2

12 h 65.6 41.0 28.6 17.8 15.0 12.8 9.3 6.8

1 d 65.1 38.7 25.8 14.9 12.2 10.0 6.8 4.7

2 d 64.4 35.2 22.1 11.8 9.3 7.4 4.7 2.9

3 d 62.8 32.2 19.3 9.8 7.6 6.0 3.6 2.1

1 wk 62.3 29.0 16.3 7.7 5.8 4.5 2.5 1.4

2 wk 65.5 30.5 17.1 8.1 6.2 4.7 2.7 1.6

1 mo 72.4 34.7 19.9 9.8 7.6 6.0 3.7 2.2

2 mo 85.7 39.8 22.8 11.8 9.5 7.8 5.1 3.3

4 mo 90.7 40.4 23.0 12.5 10.5 9.0 6.4 4.4

6 mo 94.6 42.5 24.5 13.9 11.9 10.4 7.7 5.5

9 mo 116.7 54.5 32.5 19.6 17.2 15.4 11.8 8.8

1 y 166.1 81.2 50.3 31.7 28.2 25.6 20.1 15.2

2 y 494.2 251.9 160.5 104.2 93.6 85.3 68.0 52.3

Table 2. Beta-to-Gamma Dose Ratios for Bare Skin Exposures

to Mixed Fission Products at the Nevada Test Site

Time t after 

Detonation

Distance h from source plane (cm)

1 20 40 80 100 120 160 200

0.5 h 36.0 24.6 18.3 12.4 10.8 9.6 7.6 5.9

1 h 32.2 21.8 16.1 10.8 9.4 8.2 6.4 4.9

2 h 31.6 21.2 15.5 10.3 8.9 7.8 6.1 4.6

4 h 40.1 26.6 19.3 12.7 10.9 9.5 7.3 5.6

6 h 50.5 33.3 24.0 15.7 13.4 11.7 9.0 6.9

12 h 64.7 41.8 29.7 18.7 15.9 13.7 10.2 7.6

1 d 64.2 39.6 26.9 15.9 13.0 10.9 7.7 5.4

2 d 63.4 36.3 23.3 12.7 10.1 8.2 5.4 3.5

3 d 62.0 33.4 20.5 10.7 8.4 6.7 4.2 2.6

1 wk 61.6 30.3 17.5 8.4 6.4 5.0 3.1 1.8

2 wk 64.7 31.9 18.4 8.9 6.8 5.3 3.3 2.0

1 mo 71.6 36.2 21.3 10.7 8.3 6.7 4.3 2.7

2 mo 84.6 41.5 24.3 12.6 10.2 8.5 5.9 3.9

4 mo 89.4 42.2 24.4 13.3 11.1 9.6 7.1 5.0

6 mo 93.4 44.3 26.0 14.6 12.5 11.0 8.5 6.2

9 mo 114.7 56.5 34.3 20.3 17.8 16.0 12.8 9.7

1 y 164.0 84.3 52.9 32.8 29.1 26.5 21.7 16.8

2 y 487.7 260.5 168.1 107.5 96.1 88.1 72.9 57.3
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In addition to fission products, fallout contains “unburned” fissile materials (e.g., U-235

and Pu-239) and other radionuclides of the actinium series of elements, which constitute 

additional sources of beta and gamma radiation. The external contribution of actinides to 

skin dose is expected to be small for most detonations and exposure scenarios. However, 

for fallout from thermonuclear devices, the beta-to-gamma dose ratios for times less than 

a few weeks and distances within a few centimeters of a contaminated surface can 

increase significantly from those listed in Table 1 due to the additional presence of 

actinides. The predominant actinide contributors to a thermonuclear fallout radiation field 

are U-237, U-240, Np-239, and Np-240m (i.e., isomeric state of Np-240) (Barss and 

Weitz, 2006). The beta-to-gamma dose ratios for thermonuclear fallout with significant 

actinide content (Operation CASTLE Shot BRAVO being prototypical of this class) are 

given in Table 3.

Table 3. Beta-to-Gamma Dose Ratios for Bare Skin Exposures to Mixed

Fission Products and Actinides at Pacific Test Sites

Time t after 

Detonation

Distance h from source plane (cm)

1 20 40 80 100 120 160 200

1 h 33.8 21.6 15.6 10.3 8.9 7.7 5.8 4.4

2 h 35.6 22.0 15.4 10.0 8.6 7.5 5.6 4.2

6 h 65.9 37.0 24.3 15.0 12.8 11.1 8.1 6.0

12 h 76.4 39.9 24.9 14.6 12.3 10.5 7.5 5.4

1 d 102.8 46.8 26.3 13.8 11.3 9.4 6.4 4.3

2 d 103.2 44.2 23.8 11.7 9.4 7.7 5.1 3.3

1 wk 105.3 33.3 14.3 5.2 3.8 2.8 1.6 0.9

2 wk 84.1 32.0 15.6 6.6 4.9 3.8 2.2 1.2

1 mo 77.5 35.0 19.5 9.4 7.3 5.7 3.5 2.1

2 mo 85.7 39.8 22.8 11.8 9.5 7.8 5.1 3.3

6 mo 94.6 42.5 24.5 13.9 11.9 10.4 7.7 5.5

1 y 166.1 81.2 50.3 31.7 28.2 25.6 20.1 15.2

2 y 494.2 251.9 160.5 104.2 93.6 85.3 68.0 52.3

Activated soil at NTS test locations was another infinite plane source (neutron-activated 

soil is generally not a source of exposure for PPG participants). Activation products are 

produced by neutron absorption in materials. The radioisotopes Na-24, Mn-56, Si-31, Cl38, and K-42 are the primary contributors to the gamma and beta radiation in the vicinity 

of activated NTS soil for the first few weeks after detonation, with Cs-134, Sc-46, , and 

Ca-45 dominant at later times (e.g., months to years after the detonation). Aluminum 

activation products (e.g., Al-28) decayed to immeasurable levels within minutes after a 

detonation and, therefore, did not contribute to skin dose by the time test participants 

entered contaminated areas. 

Beta-to-gamma dose ratios for neutron activation products in soil were calculated from 

their respective parent elemental abundances and neutron capture cross sections by 
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calculating an activity depth profile for 12 radionuclides to a depth of 30 cm (51 g cm−2). 

Dose ratios were calculated out to 10,000 h post-detonation for four stay times 

(designated Δt) in areas of NTS activated soil at Area 7 and Frenchman Flat. The four 

stay times include the limiting case of Δt approaching zero (very short stay times) to 

Δt = 100 h. The calculated dose ratios for the limiting case are shown in Table 4, and 

ratios for additional stay times of 1 h, 10 h, and 100 h are available in Weitz and Egbert

(2017). The limiting values shown in Table 4 are generally slightly higher (i.e., a few 

percent) than the more typical stay time of 1 h. (Weitz and Egbert, 2017)

The beta-gamma ratios for neutron-activated soil shown above are not used for 

participants that were present in the soil activation areas near GZ following the 

Hiroshima and Nagasaki detonations in Japan. For these participants, single high-sided 

values are used to bound the exposures for all body locations (heights) and times of 

possible entry of the occupation troops or prisoners of war (POWs). Constant betagamma ratios of 0.03 and 0.02 are used for occupation troops who were in the vicinity of 

the Hiroshima or Nagasaki GZ, respectively. For all POWs that passed near either GZ, a 

beta-gamma ratio of 0.2 is used. 

5.2.1.2 Modification Factor

The beta-to-gamma dose ratios reported in Table 1, Table 2 and Table 3 apply to 

exposures of bare skin to infinite fallout fields. Frequently the target site on the body was 

covered by an article of clothing during the period of exposure. Clothing strongly 

attenuates beta particles but does not affect the gamma dose recorded on a properly worn 

film badge. Thus, if the skin site of interest was covered by even a relatively thin layer of 

clothing during the exposure, the beta-to-gamma dose ratios can be significantly reduced. 

A modification factor (M) is used to adjust the dose ratios to account for the additional 

beta shielding provided by clothing. Values of M applicable for exposures to mixed 

fission products when wearing a layer of clothing 28 mg cm−2 in density-thickness, 

representative of “coverall” material, are provided in Table 5 (Barss and Weitz, 2006). 

Except for locations close to the source plane, the presence of this clothing reduces the 

beta dose by 10 to 30 percent. 
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Table 4. Beta-to-Gamma Dose Ratios for Bare Skin Exposures to NeutronActivated Soil at NTS for Very Short Stay Times (Δt → 0)

Entry Time t

after Detonation

(h)

NTS Area 7 at Height = NTS Frenchman Flat at Height =

1 cm 100 cm 160 cm 1 cm 100 cm 160 cm

0.1 6.12×10−1 3.52×10−1 2.57×10−1 6.15×10−1 3.55×10−1 2.59×10−1

0.2 5.86×10−1 3.31×10−1 2.41×10−1 6.01×10−1 3.42×10−1 2.49×10−1

0.5 4.35×10−1 2.09×10−1 1.46×10−1 4.59×10−1 2.22×10−1 1.56×10−1

1 4.20×10−1 1.99×10−1 1.38×10−1 4.32×10−1 2.03×10−1 1.41×10−1

2 4.00×10−1 1.88×10−1 1.30×10−1 3.99×10−1 1.82×10−1 1.24×10−1

3 3.83×10−1 1.79×10−1 1.23×10−1 3.73×10−1 1.67×10−1 1.13×10−1

4 3.66×10−1 1.70×10−1 1.17×10−1 3.49×10−1 1.55×10−1 1.04×10−1

5 3.49×10−1 1.62×10−1 1.11×10−1 3.28×10−1 1.44×10−1 9.58×10−2

6 3.33×10−1 1.54×10−1 1.05×10−1 3.07×10−1 1.34×10−1 8.84×10−2

7 3.18×10−1 1.46×10−1 9.97×10−2 2.88×10−1 1.24×10−1 8.16×10−2

8 3.03×10−1 1.39×10−1 9.45×10−2 2.70×10−1 1.15×10−1 7.52×10−2

9 2.90×10−1 1.32×10−1 8.97×10−2 2.54×10−1 1.07×10−1 6.95×10−2

10 2.78×10−1 1.26×10−1 8.54×10−2 2.39×10−1 9.96×10−2 6.43×10−2

12 2.57×10−1 1.16×10−1 7.80×10−2 2.15×10−1 8.75×10−2 5.57×10−2

15 2.35×10−1 1.04×10−1 7.00×10−2 1.90×10−1 7.51×10−2 4.69×10−2

20 2.15×10−1 9.37×10−2 6.23×10−2 1.69×10−1 6.43×10−2 3.92×10−2

24 2.06×10−1 8.90×10−2 5.88×10−2 1.61×10−1 6.03×10−2 3.63×10−2

36 1.94×10−1 8.14×10−2 5.29×10−2 1.53×10−1 5.54×10−2 3.26×10−2

48 1.85×10−1 7.59×10−2 4.87×10−2 1.49×10−1 5.27×10−2 3.05×10−2

72 1.71×10−1 6.70×10−2 4.16×10−2 1.42×10−1 4.84×10−2 2.71×10−2

120 1.56×10−1 5.56×10−2 3.23×10−2 1.36×10−1 4.29×10−2 2.27×10−2

168 1.79×10−1 5.83×10−2 3.19×10−2 1.49×10−1 4.27×10−2 2.21×10−2

200 2.34×10−1 7.32×10−2 3.96×10−2 1.70×10−1 4.55×10−2 2.41×10−2

250 2.86×10−1 8.79×10−2 4.78×10−2 1.82×10−1 4.59×10−2 2.49×10−2

300 2.78×10−1 8.45×10−2 4.61×10−2 1.75×10−1 4.28×10−2 2.33×10−2

400 2.45×10−1 7.20×10−2 3.93×10−2 1.58×10−1 3.64×10−2 1.99×10−2

500 2.15×10−1 6.11×10−2 3.33×10−2 1.44×10−1 3.09×10−2 1.69×10−2

700 1.68×10−1 4.38×10−2 2.39×10−2 1.22×10−1 2.23×10−2 1.22×10−2

1,000 1.22×10−1 2.66×10−2 1.45×10−2 9.99×10−2 1.37×10−2 7.46×10−3

1,400 8.30×10−2 1.16×10−2 6.30×10−3 8.24×10−2 6.05×10−3 3.29×10−3

2,000 6.72×10−2 5.05×10−3 2.73×10−3 7.68×10−2 2.71×10−3 1.46×10−3

3,000 6.07×10−2 1.06×10−3 5.37×10−4 7.83×10−2 6.56×10−4 3.27×10−4

4,000 6.28×10−2 3.64×10−4 1.44×10−4 8.38×10−2 3.10×10−4 1.25×10−4

5,000 6.60×10−2 2.74×10−4 7.91×10−5 8.90×10−2 2.81×10−4 9.36×10−5

7,000 6.97×10−2 3.22×10−4 7.12×10−5 9.45×10−2 3.44×10−4 9.36×10−5

10,000 6.69×10−2 4.01×10−4 7.11×10−5 8.89×10−2 4.22×10−4 9.12×10−5
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Table 5. Modification Factor for Light Clothing for Exposures to Mixed Fission 

Products

Time after 

detonation

Distance from source plane (cm)

1 20 40 80 100 120 160 200

1 h 0.59 0.74 0.80 0.83 0.84 0.86 0.87 0.87

2 h 0.59 0.73 0.79 0.84 0.84 0.85 0.87 0.87

6 h 0.57 0.72 0.78 0.83 0.84 0.85 0.86 0.87

1 d 0.52 0.67 0.73 0.78 0.80 0.81 0.82 0.83

1 wk 0.40 0.54 0.66 0.71 0.72 0.74 0.74 0.78

2 wk 0.40 0.55 0.66 0.71 0.72 0.73 0.77 0.74

1 mo 0.41 0.56 0.67 0.73 0.74 0.75 0.78 0.77

1 y 0.42 0.62 0.78 0.86 0.87 0.87 0.88 0.88

Heavier articles of clothing, such as footwear and field jackets, attenuate the beta dose, 

and thereby reduce the dose ratios, more significantly. The beta-to-gamma dose ratio for 

the heel of a foot inside a boot is an extreme example. Values of beta-to-gamma dose 

ratios for this exposure scenario are shown in Table 6. These results were obtained by 

assuming that a boot sole of 750 mg cm−2density-thickness separated the heel from the 

radiation source.

Table 6. Beta-to-Gamma Dose Ratios for Heel of Foot

inside a Boot

Time Beta-to-Gamma Dose Ratio

1 h 0.368

1 d 0.181

1 wk 0.013

1 mo 0.041

1 y 1.10

A general formulation to estimate beta-to-gamma dose ratios for arbitrary thicknesses of 

material between the source plane and the target location was developed by performing a 

regression analysis of calculated values of R. These results are expressed as exponential 

functions with time-dependent coefficients (Barss, 2000):

B(t )x

/ R ( x,t ) A(t ) e



 



(1)
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where

Rx,t)  Beta-gamma dose ratios

A(t) = Coefficient given in Table 7

B(t) = Coefficient given in Table 7

x = Density-thickness of air, clothing, epidermal layer, or other

shielding material between source and basal layer (mg cm−2)

t = time after detonation (h)

This representation of R agrees well with transport-calculated values for densitythicknesses in the range 100 to 500 mg cm−2

.

Table 7. Coefficients to Calculate Beta-to-Gamma Dose Ratios

Time (t) A(t) B(t) (cm2 mg−1)

1 h 17.0 5.43E−03

2 h 16.7 5.66E−03

4 h 19.6 5.53E−03

6 h 23.9 5.47E−03

12 h 29.0 5.82E−03

1 d 27.1 7.09E−03

2 d 26.5 8.97E−03

3 d 26.0 1.02E−02

1 wk 22.6 1.13E−02

2 wk 22.3 1.08E−02

1 mo 24.5 9.82E−03

2 mo 26.2 8.48E−03

4 mo 24.6 7.06E−03

6 mo 25.9 6.28E−03

9 mo 30.4 4.90E−03

1 y 55.1 5.17E−03

2 y 192 5.50E−03

The following example demonstrates the application of Equation 1 for estimating R. An 

individual wore both a tee-shirt and a fatigue jacket, each with an estimated thickness 

equivalent to that of “coverall” material cited above (28 mg cm−2), covering his upper 

torso when exposed in a large fallout field 6 hours after a nuclear detonation at NTS. He 

later developed skin cancer on his lower back, at a height of 120 cm. In this case, 
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A(6 h) = 23.9 and B(6 h) = 0.00547 from Table 7. The density-thickness x consists of the 

contributions from air, clothing, and epidermal layer. The thickness of air from source 

plane to cancer site is 120 cm; the air density-thickness is obtained by multiplying this 

(linear) thickness by the density of air, typically taken as 1.05 mg cm−3at NTS (for 

exposures at Pacific sites, 1.15 mg cm−3is more representative). Thus, the air densitythickness is 120 cm×1.05 mg cm−3 = 126 mg cm−2

. The density-thickness of the clothing 

he wore over the nascent cancer site during exposure is 2 layers×28 mg cm−2 per layer =

56 mg cm−2, and the density-thickness of the epidermal layer is normally taken as 

7 mg cm−2. Therefore, the combined density-thickness x = 189 mg cm−2. Substituting into 

Equation 1 gives the example:

23 9 8 5

0 00547 189 R . e ..

/  

 

 

(2)

A modification factor of M = 0.7/0.5 = 1.4 has occasionally been applied to the infiniteplane beta-to-gamma dose ratios to remove the aforementioned body shielding factors for 

application to face-on exposures. This correction is not exact, however, because the 

distance between the film badge and the source plane assumed in formulating the infiniteplane ratios is 1.37 m, while the film badge-source distance in a facing exposure may be 

much different from that. Because the sources in virtually all facing exposure scenarios

do not qualify as “infinite” (reference definition of “infinite plane source” in Section 4), it 

is recommended that the finite source formulation presented in Section 5.2.2 be used in 

these cases.

5.2.1.3 Skin Dose from Acute Exposures

For an acute exposure (e.g., one for which a single-day mission film badge was issued) to 

an infinite fallout or activation field, the beta dose at a body target location can be 

computed using Table 1–Table 4, and the following general equation:

D D [ R ( h,t ) M ] skin  fb   /  

(3)

where

Dβskin = Bare-skin beta dose from exposure to fallout or activation products

(rem)

Dfb = Film badge (or film badge-equivalent) dose accrued over the same 

time interval (rem)
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Rβ/γ(h,t) = Ratio of beta dose to film badge (equivalent) dose as function of 

distance (h in m) and time after detonation (t in h)

M = Modification factor (see Table 5 for light clothing; if it is uncertain 

that an individual wore clothing over the target skin site during 

exposure, the default is to assume that he did not and set M = 1)

The total skin dose (Dskin) from deposited fallout or activation products is obtained by 

adding the gamma (film badge) dose to the beta skin dose as shown in the equation:

D D [ R ( h,t ) M ] skin  fb   /   1

(4)

Skin doses at NTS were typically accrued by maneuver troops and observers 0.5–2 h

after a detonation. Note from Table 2 that the beta-to-gamma dose ratios are 

approximately constant over that time interval. Therefore, a simple method of calculating 

such skin doses is to use the value of R at t = 0.5 h (the largest for that time period) in 

Equation 4. The integrating methodology discussed below for chronic exposures can be 

used for periods longer than 0.5 to 2 h.

5.2.1.4 Skin Dose from Chronic Exposures

For chronic exposures, it is assumed that an individual was exposed to beta radiation 

from fallout only while he was outside. The beta skin dose from an infinite fallout field is 

reconstructed by integrating the product of the gamma intensity and the beta-to-gamma 

dose ratio over the period of exposure while properly accounting for location (inside vs. 

outside) and body position (standing vs. sitting). The beta skin dose is thus computed 

with the following equation:

D . F I (t )[ f R ( h ,t ) f R ( h ,t )] dt std / std sit / sit

t

t

skin OS

end

start

    

       0 7

(5)

where

tstart = Time after detonation at which exposure started (h)

tend = Time after detonation at which the exposure ended (h)
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Iγ(t) = Gamma intensity at time t after detonation (this may be based on 

independent intensity measurements or derived on the basis of a 

film badge reading) (R h−1)

Rβ/γ(h,t) = Beta-to-gamma dose ratio

hstd = Distance from source plane to target site on body for person

standing upright in infinite fallout field, calculated using height of 

individual (m)

hsit = Distance from source plane to target site on body for person sitting 

in infinite fallout field, calculated using height of individual (m)

0.7 = Film badge conversion factor

Fos = Fraction of time spent outside

fstd = Fraction of outside time in standing position

fsit = Fraction of outside time in sitting position

The resulting beta dose is summed with its corresponding film badge (equivalent) gamma

dose to determine the skin dose for each fallout episode; a sum of skin dose over fallout 

episodes yields the central estimate of the total skin dose. 

Reference distances above a source plane for three positions are shown in Table 8. These 

reference distances were determined for a veteran height of 68 inches (173 cm) using 

Reference Man values, together with modifying factors for the two sitting positions for 

anatomical locations at mid-thigh and above (Stiver, 2008). To determine values for hstd

and hsit for veteran heights other than 68 inches, multiply the appropriate reference 

distance(s) in Table 8 (except foot/ankle) by the ratio of veteran height to 68 inches. For 

foot and ankle sites, the reference distances are used for all veteran heights. For example, 

the distance of “face” above the plane for a standing veteran of height 72 inches is 

63 inches  (72/68) = 66.7 inches.
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Table 8. Reference Distances above a Plane for Various Anatomical Locations

Reference Distances (inches) for Three Positions*

Anatomical 

Location Standing Sitting(chair/bench)

Sitting

(ground/deck)

foot and ankle 0.4 0.4 2.0

shin 8.0 8.0 6.0

knee 16.0 16.0 6.0

mid-thigh 28.0 20.9 6.0

hand 28.0 20.9 6.0

waist 39.0 22.2 5.5

forearms 39.0 22.2 8.0

stomach 47.0 30.2 13.5

mid-chest 55.0 38.2 21.5

neck 59.0 42.2 25.5

face and head/eyes 63.0 46.2 29.5

top of head 68.0 51.2 34.5

* Reference distances are for a veteran height of 68 inches (173 cm). 

5.2.2 Finite Plane Source 

Many radiation sources do not qualify as infinite, as defined in Section 4. Finite radiation 

sources were encountered, for example, by crewmembers exposed to topside fallout 

while aboard ship, by mechanics performing maintenance on contaminated aircraft 

engines, and by members of a decontamination team cleaning a contaminated vehicle. In 

such cases, an application of a beta-to-gamma dose ratio based on the infinite source 

model may significantly underestimate the beta dose. To address this limitation the 

methodology was extended to more accurately reconstruct skin doses from exposures to 

spatially finite radiation sources (Weitz, 2011). 

While a beta dose from exposure to an infinite plane source depends on time after 

detonation (t) and distance from source (h), a similar dose resulting from an exposure to a 

finite source depends also on the spatial dimension of the source. The methodology 

described above for infinite sources was generalized to accommodate the additional 

independent variable by making two simplifying approximations:

 A radiation source of area A and arbitrary shape is represented as a circular source of

the same area, facilitated by defining an “equivalent radius” of

r  A  . 

 The subject is located at the center of this circular source region.

Two-dimensional Monte Carlo transport methods coupled with a source-target transform 

technique (Weitz, 2011) were employed to calculate the beta and gamma doses to 

sensitive skin layers from axial exposures to circular fallout sources ranging in radius 

from 0.1 m to 500 m (the latter qualifying as infinite), for times from 1 hour to 1 year
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after detonation, and for three substrate materials (soil, aluminum, and iron). These doses

are provided in Attachment 1 in units of mrad per unit surface emission density (i.e., 

mrad β−1cm2for beta dose Dβ, and mrad γ−1cm2for gamma dose Dγ). 

5.2.2.1 Skin Dose from Acute Exposures

The following formulations are taken from Weitz (2011).

For a person exposed to a finite fallout-contaminated area while wearing a film badge, 

the bare skin dose Dskin at the target location on his body can be estimated using the 

equation:

fb

fb fb

t t

t

t

skin D

M D (t,h ,r,mat )

M N (t ) D (t,h ,r,mat ) M D (t,h ,r,mat )

D 





 

    

(6)

Where

Dβ(t,h,r,mat) = Beta dose (mrad β

−1

cm2) for parameters t, h, r, and substrate 

material mat, obtained from appropriate table in Attachment 1

Dγ(t,h,r,mat) = Gamma dose (mrad γ

−1

cm2) for parameters t, h, r, and substrate 

material mat, obtained from appropriate table in Attachment 1

Dfb = Reading on film badge (rem)

hfb = Distance of the film badge from the source plane during

exposure (m)

ht = Distance of the target site from the source plane during 

exposure (m)

Nβγ(t) = Ratio of beta to gamma emission rates at time t (Finn et al., 1979); 

these values are provided in Table 9

Mβt = Modifying factor accounting for body shielding of beta radiation at 

the target skin site

Mγt = Modifying factor accounting for body shielding of gamma 

radiation at the target skin site

Mγfb = Modifying factor accounting for body shielding of gamma 

radiation at the film badge position

The modifying factors (M) are all unity for an individual exposed while facing the source. 

If the individual was exposed while standing upright in a fallout field, Mβt = 0.5, Mγfb = 

0.7, and Mγt can range from 0.7 for skin sites on the trunk of the body to 1 for sites on the 

extremities.
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Table 9. Beta-to-Gamma Emission Rate

Ratios N(t) at Selected Times after Detonation.

Time after Detonation (t) N(t)

1 h 0.640

1 d 0.948

1 wk 1.05

1 mo 1.38

6 mo 1.86

1 y 3.25

As an example of reconstructing a skin dose on the basis of a film badge reading, 

consider a person who accrued a film badge dose of 10 mrem while standing in a 

localized fallout field of 10-meter radius at NTS 1 hour after the detonation. The 

requirement is to reconstruct the skin dose to his hand (Mt= 1), assumed in this example 

to have been 1 m above the ground during exposure. This analysis is performed as 

follows:

Step 1: From Table A1-1 (since the contamination was deposited on soil and exposure 

took place at t = 1 h), obtain D (1 h, 1 m, 10 m, soil) = 4.47×10−7 mrad 

−1

cm2 and D (1 h, 1 m, 10 m, soil) = 1.85 ×10−5 mrad 

−1

cm2.

Step 2: Also from Table A1-1, obtain D (1 h, 1.37 m, 10 m, soil) = 3.95×10−7

mrad 

−1

cm2 .

Step 3: N (1 h) = 0.640 from Table 9; Mt = 0.5 and Mfb = 0.7 for a standing 

exposure. 

Therefore, using Equation 6 yields:

10 230 mrem

0 7 3 95 x 10

0 5 0 64 1.85 x 10 1 4.47 x 10

-7

-5 -7





 ( )

( . )( . )

( . )( . )( ) ( )( )

Dskin

(7)

If a radiation intensity reading was taken in the vicinity of the contaminated surface at the 

time of the exposure, or at some other time and can be scaled (perhaps via t

−1.2) to the 

time of exposure, the skin dose can be estimated using one of the following two 

equations, depending on the type of measurement made. For a gamma-only (closed 

window) measurement, the skin dose can be estimated using:
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I (t ) t

D (t,h ,r,mat )

M N (t ) D (t,h ,r,mat ) M D (t,h ,r,mat )

D

m

t t

t

t

skin 









    

0.877

(8)

where

0.877 = The conversion factor from mR to mrad (in air)

Iγ (t) = Gamma intensity at time of exposure (mR h

−1

)

Δt = Duration of exposure (h)

hm = Distance of the detector from the contaminated plane at time of 

intensity measurement.

Other parameters in Equation 8 were defined previously.

If the intensity measurement is gamma plus beta (open window), the skin dose can be 

estimated using:

Dskin =

Mβt Nβγ(t) Dβ(t, ht, r, mat) + Mγt Dγ

(t, ht

, r, mat)

Dγ

(t, hm, r, mat) + 0.9 Nβγ(t) Dβ(t, hm, r, mat)

Iγ+β(t) ∆t

(9)

where

Iγ+ (t) = beta plus gamma intensity reading at time of exposure, in mrad h

−1

;

Other parameters in Equation 9 were defined previously.

NOTE: Intensity measurements were typically made with a Geiger-Muller (GM) 

instrument during/after decontamination activities; hence both beta and gamma radiation 

was detected. However, many historical reports and records do not specify instrument 

and window details. In the absence of specific information, it is presumed that a reported 

intensity is exclusively gamma. This tends to high-side the skin dose. 

As an example of reconstructing a skin dose on the basis of an intensity reading, consider 

a mechanic who spent 5 hours working on a contaminated aircraft 1 day after the 

detonation. The intensity was measured at that time to be 10 mR h

−1

( only) at a distance 

of 10 cm from the surface of the aircraft, and the contaminated section had a radius of 

approximately 0.5 m. During this task, the mechanic faced toward the aircraft with his 

body, on average, a distance of 1 m from the contaminated surface. The skin site of 

interest is on his face. To estimate the skin dose using Equation 8, follow the steps below:
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Step 1: From Table A1-8 (since the contamination was deposited on the aluminum 

surface of the aircraft and exposure took place at t = 1 day), obtain D (1 day, 

1 m, 0.5 m, Al) = 1.56×10−8 mrad 

−1

cm2 and D (1 day, 1 m, 0.5 m, Al) = 

1.89×10−6 mrad 

−1

cm2.

Step 2: From Table A1-8, obtain D (1 day, 0.1 m, 0.5 m, Al) = 2.39 ×10−7

mrad 

−1

cm2.

Step 3: N (1 day) = 0.948 from Table 9; Mt = Mt = 1 for a face-on exposure.

Then, Equation 8 yields:

10) 5) 330 mrem.

2.39 x 10

1 0 948 1.89 x 10 1 1.56 x 10 0 877

-7

-6 -8





 ( (

( )

( )( . )( ) ( )( )

D . skin

(10)

5.2.2.2 Skin Dose from Chronic Exposures

Chronic skin exposures to finite sources, as experienced by crewmen on a topsidecontaminated ship, can be treated using the acute exposure formulation discussed above 

by dividing the exposure interval into increments, calculating the skin dose accrued 

during each time increment, and summing the results. An alternative, but numerically 

equivalent, approach is to adjust the infinite plane source beta-to-gamma dose ratios

available in Barss and Weitz (2006) to account for the finite size of a source. 

The infinite-plane dose ratio for an individual standing erect in a large fallout field can be 

written in terms of the normalized doses Dγ(t,h,r,mat) and Dβ(t,h,r,mat) of Attachment 1

as:

. D (t, . m, ,soil )

. D (t, h, ,soil )

h t ) N

 

 

 

0 7 1 37

0 5

R /





  

(11)

where

R h t) /    = The infinite-plane dose ratio for an individual standing erect

As discussed previously, the factor of 0.7 in the denominator converts free-field gamma 

dose Dγ to a film badge-equivalent dose by accounting for body shielding of the film 

badge, and the factor 0.5 in the numerator likewise accounts for body shielding of the 

target skin site from beta radiation. 
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A beta-to-gamma dose ratio for an individual standing in a finite fallout field of 

equivalent radius r deposited on material mat, denoted here by Qβ/γ(h,t,r,mat), can be 

expressed in an analogous manner:

. D (t, . m,r,mat )

. D (t, h,r,mat )

h t,r,mat ) N

0 7 1 37

0 5

Q /





  





 

(12)

The factor that converts Rβ/γ(h,t) to Qβ/γ(h,t,r,mat) is defined as the source size 

modification factor (SSMF):

D (t, h, ,soil )

D (t, h,r,mat )

D (t, . m,r,mat )

D (t, . m, ,soil )

h t )

h t,r,mat )

SSMF(t,h,r,mat )









 

 











 

 

1 37

1 37

R

Q

/

/

(13)

Equation 13 can be evaluated using the tabular data in Attachment 1. In doing so, it is 

found that SSMF formulated in this manner is nearly independent of time, as seen in

Figure 3. Furthermore, SSMF is nearly independent of h when r is greater than 7 meters. 

Thus, for r > 7 meters and mat = iron (a representative substrate for ship applications), 

values of SSMF can be read directly from Figure 3, irrespective of h and t. This greatly 

facilitates the calculation of skin dose from chronic exposure to fallout using existing

parameterizations of the infinite-plane dose ratios, since SSMF can be treated as a 

constant in the summation or integration process.

This formulation is particularly useful when reconstructing skin doses to crewmen from 

chronic exposure to topside contaminants on naval vessels. The weather decks of most 

ships can be approximated as ellipses with area A = 1⁄4 πBL, where B is the beam 

(maximum width) of the ship and L is its length; the corresponding equivalent radius 

r 1⁄2 BL

. The weather decks of aircraft carriers are approximately rectangular with 

area A = BL and equivalent radius 

r  BL/

. The decks of small boats can have either 

configuration, as illustrated in Attachment 2. Values of SSMF derived on this basis are 

shown in Table 10 for a representative sample of Navy ships and small boats (h = 1 m is 

assumed when r < 7 m). The dimensions for ships listed in Attachment 2 and used in this 

analysis were obtained for specific vessels of each type and may vary somewhat within 

each category; boat dimensions were taken from Attachment 2. It is seen that the 

ship-specific SSMF values agree well with the generic value of 2 that has typically been 

used. The SSMF values of small boats are somewhat larger.
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Figure 3. SSMF as Function of Source Radius for Various Times after Detonation

Table 10. SSMF for Specific Naval Vessels

1

2

3

4

5

6

0 5 10 15 20 25 30 35 40 45 50

Source Radius r (meters)

SSMF

T = 1 hour

T = 1 day

T = 1 week

T = 1 month

T = 6 months

T = 1 year

Equivalent

Vessel Type Designation Beam [m] Length [m] Radius [m] SSMF

Ships:

Aircraft Carrier CVS 28 271 49 1.5

Attack Transport APA 19 139 26 1.8

Destroyer DD 12 115 19 2.0

Dock Landing Ship LSD 22 140 28 1.8

Fleet Tug ATF 12 62 14 2.2

Salvage Ship ARS 12 65 14 2.2

Store Ship AF 15 103 20 2.0

Tank Landing Ship LST 15 100 20 2.0

Small Boats:

Whale Boat 2.4 7.9 2.5 6.0

LCVP 3.2 10.9 3.3 4.7

LCM 6 4.3 17.1 4.8 3.8

LCM 8 6.4 22.5 6.8 3.2

LCU 1466 class 10.4 36.3 11.0 2.5

LCU 1600 class 8.8 41.1 10.7 2.5
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The SSMF can also be evaluated for face-on exposures to sources of finite size. The betato-gamma dose ratio for a person who, at time t, faces a source of equivalent radius r

deposited on material mat is given by:

( , , , )

( , , , )

, , )

D t h r mat

D t h r mat

Q h t r mat N

f b

/





 

  

(14)

In Equation 14, h and hfb are the distances of the target body site and film badge, 

respectively, from the source plane during exposure. The values of h and hfb may differ if 

the target site is on the hand or forearm, which is likely to have been closer to the source 

than was the torso (film badge) during decontamination and maintenance operations. 

Note that the body shielding factors do not apply in this case. The corresponding SSMF is 

then:

0.5 ( , , , )

( , , , )

( , , , )

0.7 ( ,1.37 , , )

)

, , )

( , , , )

D t h soil

D t h r mat

D t h r mat

D t m soil

R h t

Q h t r mat

SSMF t h r mat

f b /

/

 



 



 

 











 

 

 (15)

As an example, consider an exposure to a contaminated aircraft engine (mat = aluminum, 

r = 0.5 m) from a distance h = hfb = 1 m at t = 1 h. Normalized doses from Tables A1-1 

and A1-7 are substituted into Equation 15 to obtain:

6.2

0.5 1.86 10

2.21 10

2.41 10

0.7 8.93 10 SSMF(1 hr, 1 m, 0.5 m, Al)

5

6

8

7



 







 

 







(16)

5.2.3 Point Source

A source that is spatially small compared to the source-target distance is considered a 

point source. Point source geometry has been used in skin dose reconstructions of

exposures to radiological “hot spots” such as ship scuppers, aircraft landing gear after 

decontamination, and cloud sampling filters containing non-uniformly distributed 

activity. Typically the gamma intensity in the vicinity of the point source was measured

or can be estimated. The skin dose accrued while facing a point source can be determined 

by applying either Equation 8 or Equation 9, depending on the type of intensity 

information available, with modifying factors Mt = Mt = 1 (for a face-on exposure) and 

source radius r = 0.1 m. The doses Dγ and Dβ are obtained from Attachment 1.
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5.3 Volumetric Source: Skin Dose from Swimming in Contaminated Water

Radiation exposure to the skin may have occurred from fallout-contaminated or neutronactivated sources suspended in seawater when the individual was submerged in the water, 

such as while swimming or diving. 

For skin dose associated with fallout-contaminated seawater, it is assumed the water was 

uniformly contaminated with unfractionated fallout of age t, measured from the time of 

detonation. The gamma dose, Dγ, accrued in fallout-contaminated water is shown in 

SM ED02 - Whole Body External Dose Assessment is approximated by:

Dγ = 1.4 Iff ∆t (17)

where

Dγ = External gamma dose accrued by a swimmer during the short 

duration of swimming Δt (rem)

Iff = Free-field gamma intensity above the water surface, assumed to be 

constant over the short duration of swimming Δt (R h−1)

Δt = Time spent in the contaminated water (h)

Based on the analysis in Weitz (2012), the beta skin dose for immersion in falloutcontaminated seawater is less than half of the gamma dose for all times less than about 

6 months post-detonation. For times of typical exposure scenarios, e.g., between 100 and 

500 hours after a detonation, the beta skin dose is roughly one-third or less of the gamma 

dose.

For skin dose associated with neutron-activated seawater, Na-24, K-42, and Br-82 were

the dominant radioisotopes relevant to an immersion scenario produced in a low-altitude

nuclear detonation above or in seawater (Weitz, 2012). The gamma and beta doses 

accrued while swimming for a duration Δt in this neutron-activated seawater are 

estimated using the following equations (Weitz, 2012):

Dγ = 1.4 Iff ∆t

Dβ = 0.13 Iff ∆t

(18)

(19)

In both cases, the gamma and beta doses are added to determine the total skin dose.
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5.4 Uncertainty Analysis

The methods employed to identify, quantify, and combine uncertainties in internal dose 

estimates are detailed in SM UA01 - Dose Uncertainty and Upper-Bound Dose 

Determinations. Operation-, scenario-, and shot-specific information and data needed to 

address uncertainty analysis for internal doses are contained in SOP Appendices A-C.

6. Data and Input

Operation and shot-specific data are compiled in SOP Appendices A-C. 

Due to the limited range of beta particles and their attenuation characteristics, skin dose 

assessments require consideration of additional details not normally relevant in gamma 

dose reconstructions. The parameters that must be defined specifically for skin dose from 

external sources assessments are listed below. Specific values of these parameters should 

be determined to the extent possible from statements made by the veteran in his Scenario 

of Participation and Radiation Exposure or supporting documentation, and/or through 

personal interview. When these direct sources of information are not available, the 

analyst can review skin dose reconstructions performed for personnel in the same or 

similar units to ascertain key parameters. Finally, default values have been established for 

most parameters when more specific information is lacking, as follows:

 Veteran’s height (default = 1.73 m)

 Anatomical location(s) of skin cancer (e.g., face, forearms, behind ears)

 Fos: fraction of time spent outside when on land (default = 0.6)

 Fts: fraction of time spent topside aboard ship (default = 0.4)

 fstd: fraction of topside or outdoor time spent standing (default = 0.5)

 fsit: fraction of topside or outdoor time spent sitting (default = 0.5)

 Frequency of shore liberty for ship crew (default = 4 hours every 4 days when ship is 

near a residence island or recreational area)

 Frequency of swimming in lagoon water (default = 0 or as specified in appropriate 

SOP Appendix)

 Time spent swimming per event (default = 1 h)

For decontamination and post-decontamination work activities, use the following default 

values:

 Distance of torso from contaminated surface while decontaminating (default = an 

average of 1 meter)
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 Time spent decontaminating ship or aircraft (default = 6 hours for 1 day after each 

fallout episode)

 Fraction of decontamination time spent hosing (default = 0.5)

 Fraction of decontamination time spent scrubbing (default = 0.5)

 Time spent performing maintenance or work on decontaminated surface(s) (default = 

1 hour each day after decontamination event)

 Distance of intensity measurement from contaminated surface (default = 0.1 meter).

7. Referenced SOPs and Standard Methods from this Manual

(1) SOP RA01 - Radiation Dose Assessment for Cases Requiring Detailed Analysis

(2) SM ED02 - Whole Body External Dose Assessment

(3) SM ED04 - Skin Dose from Dermal Contamination

(4) SM UA01 - Dose Uncertainty and Upper-Bound Dose Determinations

8. References

Barss, N.M., 2000. Methods and Applications for Dose Assessment of Beta Particle Radiation -A 

Technical Reference Manual. SAIC-001-2024, Science Applications International 

Corporation, McLean, VA.

Barss, N.M., and Weitz, R.L., 2006. “Reconstruction of External Dose From Beta Radiation 

Sources of Nuclear Weapon Origin,” Health Physics, 91(4):379-389.

DoD (Department of Defense), 2020. “Guidance for the Determination and Reporting of Nuclear 

Radiation Dose for DoD Participants in the Atmospheric Nuclear Test Program (1945-

1962).” Title 32, Code of Federal Regulations, Part 218. Washington, DC. July 1.

Finn, S.P., Simmons, G.L., and Spencer, L.V., 1979. Calculation of Fission Product Gamma Ray 

and Beta Spectra at Selected Times after Fast Fission of U238 and U235 and Thermal 

Fission of U 235. SAI-78-782-LJ/F, Science Applications, Inc., McLean, VA.

ICRP (International Commission on Radiological Protection), 2002. Basic Anatomical and 

Physiological Data for Use in Radiological Protection Reference Values. ICRP 

Publication 89, Ann. ICRP 32 (3-4). International Commission on Radiological 

Protection. 

ICRU (International Commission on Radiation Units and Measurements), 1997. Dosimetry of 

External Beta Rays for Radiation Protection. ICRU Report 56, International Commission 

on Radiation Units and Measurements, Bethesda, MD. January 5.

Stiver J.S., 2008. “Calculation of Anatomical Locations Based on an Individual’s Height and 

Reference Man,” Excel Worksheet - height calculator for beta gamma ratios.xls,

Revision 3, Science Applications International Corporation, McLean, VA. September 8.
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Turner, J.E., 1995. Atoms, Radiation, and Radiation Protection, John Wiley and Sons, Inc., 2nd

Edition.

WebMD, 2019. Picture of the Skin. WebMD, LLC, New York, NY. August 07, 2019. 

https://www.webmd.com/skin-problems-and-treatments/picture-of-the-skin, Accessed 

March 29, 2021.

Weitz, R.L., 2011. Analysis of Skin Dose from Circular Sources of Fallout. NTPR-TM-11-03,

Science Applications International Corporation, McLean, VA. July 1.

Weitz, R.L., 2012. External Gamma and Skin Doses from Immersion in Contaminated Water. 

NTPR-TM-11-04, Science Applications International Corporation, McLean, VA. 

June 18.

Weitz, R.L., and Egbert, S.E., 2017. Beta Dose from Exposure to Neutron-Activated Soil, 

Revision 1. NTPR-TM-13-01 (R1), Leidos, Inc., Alexandria, VA. February 16.
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Normalized Doses for Finite Circular Sources

Gamma and beta doses to the basal cell layer of the skin from axial exposures to circular 

fallout sources are provided in this Attachment. These doses, calculated using the twodimensional transport methods described in Weitz (2011), are presented in units of mrad 

per unit surface emission density: mrad β−1cm2for beta dose and mrad γ−1cm2for 

gamma dose. The doses are organized in tables, with each table corresponding to one 

time after detonation and one substrate material. The tables are arranged in the following 

order:

 Circular Sources of Soil at 1 hour post detonation Table A1-1

 Circular Sources of Soil at 1 day post detonation Table A1-2

 Circular Sources of Soil at 1 week post detonation Table A1-3

 Circular Sources of Soil at 1 month post detonation Table A1-4

 Circular Sources of Soil at 6 months post detonation Table A1-5

 Circular Sources of Soil at 1 year post detonation Table A1-6

 Circular Sources of Aluminum at 1 hour post detonation Table A1-7

 Circular Sources of Aluminum at 1 day post detonation Table A1-8

 Circular Sources of Aluminum at 1 week post detonation Table A1-9

 Circular Sources of Aluminum at 1 month post detonation Table A1-10

 Circular Sources of Aluminum at 6 months post detonation Table A1-11

 Circular Sources of Aluminum at 1 year post detonation Table A1-12

 Circular Sources of Iron at 1 hour post detonation Table A1-13

 Circular Sources of Iron at 1 day post detonation Table A1-14

 Circular Sources of Iron at 1 week post detonation Table A1-15

 Circular Sources of Iron at 1 month post detonation Table A1-16

 Circular Sources of Iron at 6 months post detonation Table A1-17

 Circular Sources of Iron at 1 year post detonation Table A1-18
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In each table, the gamma doses are listed for vertical heights ranging from 0.1 to 2 meters 

and source sizes (radii) from 0.1 to 500 m. The gamma doses are followed by the beta 

doses for a similar range of vertical heights but with source radii extending only to 20 m 

(sufficient given the limited range of the beta emissions). For many practical applications, 

it is necessary to interpolate between these discrete values of parameters available in 

these tables. Doses for radius r = 0.1 m are appropriate for point sources, while those for

r = 500 m (gamma) and 20 m (beta) are representative of infinite plane sources.
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Table A1-1. Normalized Doses for Circular Sources with Mat = Soil and t = 1 hour

Gamma

Radius (m) Height (m)

0.1 0.2 0.6 1 1.37 2

0.10 7.54E-08 2.54E-08 3.23E-09 1.15E-09 5.34E-10 2.81E-10

0.25 2.06E-07 1.06E-07 1.83E-08 6.64E-09 3.27E-09 1.56E-09

0.50 3.13E-07 2.13E-07 5.97E-08 2.43E-08 1.29E-08 5.99E-09

1 4.10E-07 3.21E-07 1.44E-07 7.35E-08 4.48E-08 2.29E-08

2 5.01E-07 4.23E-07 2.56E-07 1.67E-07 1.19E-07 7.19E-08

3 5.54E-07 4.82E-07 3.26E-07 2.34E-07 1.81E-07 1.22E-07

4 5.92E-07 5.24E-07 3.74E-07 2.85E-07 2.29E-07 1.65E-07

5 6.20E-07 5.55E-07 4.12E-07 3.24E-07 2.69E-07 2.02E-07

7 6.63E-07 6.02E-07 4.69E-07 3.84E-07 3.29E-07 2.61E-07

10 7.08E-07 6.52E-07 5.27E-07 4.47E-07 3.95E-07 3.27E-07

15 7.59E-07 7.08E-07 5.93E-07 5.19E-07 4.68E-07 4.02E-07

20 7.94E-07 7.47E-07 6.38E-07 5.67E-07 5.19E-07 4.54E-07

50 9.03E-07 8.65E-07 7.76E-07 7.14E-07 6.70E-07 6.12E-07

100 9.79E-07 9.45E-07 8.68E-07 8.10E-07 7.69E-07 7.16E-07

200 1.04E-06 1.01E-06 9.39E-07 8.84E-07 8.45E-07 7.93E-07

500 1.08E-06 1.05E-06 9.84E-07 9.32E-07 8.93E-07 8.43E-07

Beta

Radius (m) Height (m)

0.1 0.2 0.6 1 2

0.10 1.03E-05 3.02E-06 3.08E-07 9.59E-08 1.96E-08

0.25 2.84E-05 1.29E-05 1.77E-06 5.71E-07 1.10E-07

0.50 4.09E-05 2.56E-05 5.77E-06 2.13E-06 4.20E-07

1 4.76E-05 3.58E-05 1.38E-05 6.41E-06 1.52E-06

2 4.98E-05 4.04E-05 2.17E-05 1.31E-05 4.36E-06

3 5.01E-05 4.13E-05 2.42E-05 1.61E-05 6.64E-06

4 5.02E-05 4.15E-05 2.51E-05 1.74E-05 8.04E-06

5 5.02E-05 4.15E-05 2.55E-05 1.80E-05 8.83E-06

7 5.02E-05 4.15E-05 2.57E-05 1.84E-05 9.48E-06

10 5.02E-05 4.15E-05 2.57E-05 1.85E-05 9.71E-06

15 5.02E-05 4.15E-05 2.57E-05 1.86E-05 9.76E-06

20 5.02E-05 4.15E-05 2.57E-05 1.86E-05 9.76E-06
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Table A1-2. Normalized Doses for Circular Sources with Mat = Soil and t = 1 day

Gamma

Radius (m) Height (m)

0.1 0.2 0.6 1 1.37 2

0.10 6.13E-08 2.03E-08 2.18E-09 7.61E-10 3.72E-10 2.60E-10

0.25 1.63E-07 8.34E-08 1.29E-08 4.55E-09 2.50E-09 1.22E-09

0.50 2.48E-07 1.61E-07 4.19E-08 1.65E-08 9.33E-09 4.10E-09

1 3.25E-07 2.44E-07 1.03E-07 5.10E-08 3.16E-08 1.57E-08

2 3.95E-07 3.23E-07 1.84E-07 1.17E-07 8.29E-08 4.81E-08

3 4.35E-07 3.67E-07 2.35E-07 1.66E-07 1.26E-07 8.18E-08

4 4.63E-07 3.98E-07 2.71E-07 2.01E-07 1.61E-07 1.12E-07

5 4.84E-07 4.21E-07 2.98E-07 2.30E-07 1.89E-07 1.37E-07

7 5.15E-07 4.55E-07 3.38E-07 2.73E-07 2.31E-07 1.79E-07

10 5.48E-07 4.92E-07 3.81E-07 3.17E-07 2.76E-07 2.25E-07

15 5.84E-07 5.30E-07 4.27E-07 3.67E-07 3.27E-07 2.76E-07

20 6.09E-07 5.59E-07 4.59E-07 4.00E-07 3.61E-07 3.11E-07

50 6.87E-07 6.43E-07 5.55E-07 4.99E-07 4.65E-07 4.16E-07

100 7.39E-07 6.99E-07 6.17E-07 5.63E-07 5.31E-07 4.84E-07

200 7.81E-07 7.42E-07 6.63E-07 6.11E-07 5.80E-07 5.34E-07

500 8.06E-07 7.67E-07 6.90E-07 6.38E-07 6.08E-07 5.62E-07

Beta

Radius (m) Height (m)

0.1 0.2 0.6 1 2

0.10 1.10E-05 3.23E-06 2.86E-07 8.28E-08 1.26E-08

0.25 2.85E-05 1.32E-05 1.66E-06 5.11E-07 7.52E-08

0.50 3.87E-05 2.45E-05 5.31E-06 1.82E-06 2.81E-07

1 4.32E-05 3.20E-05 1.19E-05 5.24E-06 9.78E-07

2 4.44E-05 3.47E-05 1.70E-05 9.59E-06 2.64E-06

3 4.46E-05 3.51E-05 1.83E-05 1.12E-05 3.74E-06

4 4.46E-05 3.52E-05 1.87E-05 1.17E-05 4.32E-06

5 4.46E-05 3.52E-05 1.88E-05 1.19E-05 4.61E-06

7 4.46E-05 3.52E-05 1.89E-05 1.20E-05 4.83E-06

10 4.46E-05 3.52E-05 1.89E-05 1.21E-05 4.89E-06

15 4.46E-05 3.52E-05 1.89E-05 1.21E-05 4.90E-06

20 4.46E-05 3.52E-05 1.89E-05 1.21E-05 4.90E-06
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Table A1-3. Normalized Doses for Circular Sources with Mat = Soil and t = 1 week

Gamma

Radius (m) Height (m)

0.1 0.2 0.6 1 1.37 2

0.10 5.77E-08 2.00E-08 2.09E-09 7.79E-10 3.95E-10 1.66E-10

0.25 1.58E-07 8.08E-08 1.29E-08 4.61E-09 2.59E-09 1.29E-09

0.50 2.39E-07 1.59E-07 4.24E-08 1.72E-08 9.66E-09 4.56E-09

1 3.13E-07 2.41E-07 1.03E-07 5.33E-08 3.25E-08 1.69E-08

2 3.84E-07 3.19E-07 1.85E-07 1.20E-07 8.51E-08 5.04E-08

3 4.23E-07 3.63E-07 2.35E-07 1.70E-07 1.29E-07 8.65E-08

4 4.51E-07 3.92E-07 2.72E-07 2.06E-07 1.65E-07 1.17E-07

5 4.73E-07 4.17E-07 2.99E-07 2.36E-07 1.94E-07 1.43E-07

7 5.05E-07 4.52E-07 3.42E-07 2.80E-07 2.38E-07 1.86E-07

10 5.38E-07 4.88E-07 3.86E-07 3.28E-07 2.84E-07 2.33E-07

15 5.76E-07 5.30E-07 4.34E-07 3.78E-07 3.36E-07 2.87E-07

20 6.03E-07 5.59E-07 4.68E-07 4.13E-07 3.72E-07 3.25E-07

50 6.85E-07 6.44E-07 5.67E-07 5.16E-07 4.80E-07 4.37E-07

100 7.40E-07 7.02E-07 6.33E-07 5.85E-07 5.50E-07 5.09E-07

200 7.83E-07 7.48E-07 6.84E-07 6.37E-07 6.02E-07 5.63E-07

500 8.09E-07 7.74E-07 7.13E-07 6.66E-07 6.32E-07 5.94E-07

Beta

Radius (m) Height (m)

0.1 0.2 0.6 1 2

0.10 1.13E-05 3.18E-06 1.98E-07 5.16E-08 4.83E-09

0.25 2.63E-05 1.20E-05 1.12E-06 3.04E-07 3.33E-08

0.50 3.29E-05 2.01E-05 3.41E-06 1.07E-06 1.29E-07

1 3.53E-05 2.42E-05 7.18E-06 2.96E-06 4.28E-07

2 3.57E-05 2.53E-05 9.50E-06 4.89E-06 1.06E-06

3 3.57E-05 2.54E-05 9.88E-06 5.39E-06 1.37E-06

4 3.57E-05 2.54E-05 9.95E-06 5.51E-06 1.49E-06

5 3.57E-05 2.54E-05 9.97E-06 5.54E-06 1.53E-06

7 3.57E-05 2.54E-05 9.97E-06 5.55E-06 1.55E-06

10 3.57E-05 2.54E-05 9.97E-06 5.56E-06 1.55E-06

15 3.57E-05 2.54E-05 9.97E-06 5.56E-06 1.55E-06

20 3.57E-05 2.54E-05 9.97E-06 5.56E-06 1.55E-06
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Table A1-4. Normalized Doses for Circular Sources with Mat = Soil and t = 1 month

Gamma

Radius (m) Height (m)

0.1 0.2 0.6 1 1.37 2

0.10 6.66E-08 2.25E-08 2.69E-09 9.12E-10 4.58E-10 2.90E-10

0.25 1.79E-07 9.16E-08 1.54E-08 5.41E-09 2.90E-09 1.37E-09

0.50 2.71E-07 1.81E-07 4.93E-08 2.00E-08 1.04E-08 4.94E-09

1 3.54E-07 2.74E-07 1.19E-07 6.09E-08 3.65E-08 1.90E-08

2 4.32E-07 3.61E-07 2.13E-07 1.37E-07 9.67E-08 5.81E-08

3 4.77E-07 4.12E-07 2.70E-07 1.93E-07 1.47E-07 9.82E-08

4 5.08E-07 4.46E-07 3.11E-07 2.34E-07 1.87E-07 1.33E-07

5 5.31E-07 4.73E-07 3.41E-07 2.66E-07 2.19E-07 1.63E-07

7 5.67E-07 5.12E-07 3.87E-07 3.15E-07 2.69E-07 2.12E-07

10 6.03E-07 5.53E-07 4.36E-07 3.66E-07 3.21E-07 2.64E-07

15 6.46E-07 5.99E-07 4.90E-07 4.23E-07 3.80E-07 3.24E-07

20 6.75E-07 6.32E-07 5.27E-07 4.63E-07 4.21E-07 3.66E-07

50 7.66E-07 7.29E-07 6.40E-07 5.82E-07 5.41E-07 4.92E-07

100 8.26E-07 7.94E-07 7.13E-07 6.60E-07 6.21E-07 5.74E-07

200 8.74E-07 8.46E-07 7.69E-07 7.18E-07 6.81E-07 6.34E-07

500 9.04E-07 8.78E-07 8.04E-07 7.53E-07 7.16E-07 6.72E-07

Beta

Radius (m) Height (m)

0.1 0.2 0.6 1 2

0.10 1.12E-05 3.15E-06 2.01E-07 5.29E-08 6.09E-09

0.25 2.63E-05 1.20E-05 1.15E-06 3.14E-07 3.61E-08

0.50 3.33E-05 2.04E-05 3.54E-06 1.13E-06 1.42E-07

1 3.59E-05 2.47E-05 7.51E-06 3.13E-06 4.95E-07

2 3.64E-05 2.60E-05 1.01E-05 5.35E-06 1.25E-06

3 3.64E-05 2.61E-05 1.06E-05 5.99E-06 1.67E-06

4 3.64E-05 2.62E-05 1.07E-05 6.16E-06 1.84E-06

5 3.64E-05 2.62E-05 1.08E-05 6.21E-06 1.90E-06

7 3.64E-05 2.62E-05 1.08E-05 6.23E-06 1.94E-06

10 3.64E-05 2.62E-05 1.08E-05 6.24E-06 1.95E-06

15 3.64E-05 2.62E-05 1.08E-05 6.24E-06 1.95E-06

20 3.64E-05 2.62E-05 1.08E-05 6.24E-06 1.95E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 37 of 52

Table A1-5. Normalized Doses for Circular Sources with Mat = Soil and t = 6 months

Gamma

Radius (m) Height (m)

0.1 0.2 0.6 1 1.37 2

0.10 7.27E-08 2.51E-08 2.74E-09 8.43E-10 4.48E-10 2.26E-10

0.25 1.96E-07 1.01E-07 1.58E-08 5.37E-09 2.95E-09 1.37E-09

0.50 2.97E-07 1.96E-07 5.03E-08 1.98E-08 1.06E-08 4.95E-09

1 3.86E-07 2.95E-07 1.21E-07 6.09E-08 3.64E-08 1.83E-08

2 4.69E-07 3.87E-07 2.19E-07 1.39E-07 9.76E-08 5.75E-08

3 5.14E-07 4.39E-07 2.79E-07 1.97E-07 1.49E-07 9.79E-08

4 5.46E-07 4.75E-07 3.22E-07 2.42E-07 1.91E-07 1.33E-07

5 5.71E-07 5.03E-07 3.56E-07 2.76E-07 2.24E-07 1.64E-07

7 6.07E-07 5.45E-07 4.06E-07 3.28E-07 2.75E-07 2.13E-07

10 6.46E-07 5.88E-07 4.58E-07 3.81E-07 3.30E-07 2.67E-07

15 6.89E-07 6.35E-07 5.14E-07 4.41E-07 3.91E-07 3.30E-07

20 7.19E-07 6.69E-07 5.54E-07 4.83E-07 4.33E-07 3.71E-07

50 8.11E-07 7.71E-07 6.72E-07 6.06E-07 5.58E-07 4.97E-07

100 8.75E-07 8.38E-07 7.48E-07 6.85E-07 6.39E-07 5.80E-07

200 9.24E-07 8.91E-07 8.05E-07 7.44E-07 6.97E-07 6.39E-07

500 9.53E-07 9.22E-07 8.37E-07 7.76E-07 7.30E-07 6.72E-07

Beta

Radius (m) Height (m)

0.1 0.2 0.6 1 2

0.10 1.07E-05 2.97E-06 1.48E-07 3.92E-08 6.94E-09

0.25 2.46E-05 1.10E-05 8.29E-07 2.37E-07 4.29E-08

0.50 3.11E-05 1.81E-05 2.54E-06 8.72E-07 1.68E-07

1 3.37E-05 2.22E-05 5.81E-06 2.61E-06 6.04E-07

2 3.45E-05 2.39E-05 8.86E-06 5.21E-06 1.69E-06

3 3.45E-05 2.42E-05 9.75E-06 6.32E-06 2.50E-06

4 3.46E-05 2.42E-05 1.00E-05 6.74E-06 2.96E-06

5 3.46E-05 2.43E-05 1.01E-05 6.92E-06 3.20E-06

7 3.46E-05 2.43E-05 1.02E-05 7.03E-06 3.39E-06

10 3.46E-05 2.43E-05 1.02E-05 7.05E-06 3.44E-06

15 3.46E-05 2.43E-05 1.02E-05 7.05E-06 3.44E-06

20 3.46E-05 2.43E-05 1.02E-05 7.05E-06 3.44E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 38 of 52

Table A1-6. Normalized Doses for Circular Sources with Mat = Soil and t = 1 year

Gamma

Radius (m) Height (m)

0.1 0.2 0.6 1 1.37 2

0.10 7.25E-08 2.50E-08 2.76E-09 8.53E-10 4.34E-10 2.52E-10

0.25 1.94E-07 1.01E-07 1.61E-08 5.08E-09 2.63E-09 1.35E-09

0.50 2.94E-07 1.97E-07 5.16E-08 1.93E-08 1.06E-08 5.25E-09

1 3.83E-07 2.95E-07 1.23E-07 6.06E-08 3.70E-08 1.89E-08

2 4.64E-07 3.88E-07 2.21E-07 1.40E-07 9.83E-08 5.85E-08

3 5.11E-07 4.40E-07 2.82E-07 1.98E-07 1.51E-07 1.00E-07

4 5.43E-07 4.76E-07 3.26E-07 2.42E-07 1.93E-07 1.37E-07

5 5.68E-07 5.04E-07 3.61E-07 2.77E-07 2.27E-07 1.67E-07

7 6.04E-07 5.45E-07 4.10E-07 3.29E-07 2.78E-07 2.17E-07

10 6.43E-07 5.89E-07 4.62E-07 3.84E-07 3.34E-07 2.73E-07

15 6.87E-07 6.37E-07 5.20E-07 4.45E-07 3.96E-07 3.36E-07

20 7.17E-07 6.71E-07 5.60E-07 4.87E-07 4.39E-07 3.79E-07

50 8.12E-07 7.75E-07 6.80E-07 6.12E-07 5.65E-07 5.08E-07

100 8.75E-07 8.45E-07 7.59E-07 6.94E-07 6.47E-07 5.91E-07

200 9.26E-07 8.98E-07 8.17E-07 7.54E-07 7.08E-07 6.52E-07

500 9.56E-07 9.29E-07 8.50E-07 7.88E-07 7.42E-07 6.87E-07

Beta

Radius (m) Height (m)

0.1 0.2 0.6 1 2

0.10 1.04E-05 2.90E-06 1.51E-07 4.55E-08 1.03E-08

0.25 2.45E-05 1.08E-05 8.49E-07 2.63E-07 5.77E-08

0.50 3.19E-05 1.84E-05 2.69E-06 9.80E-07 2.16E-07

1 3.53E-05 2.36E-05 6.49E-06 3.01E-06 7.83E-07

2 3.65E-05 2.61E-05 1.06E-05 6.49E-06 2.34E-06

3 3.67E-05 2.66E-05 1.21E-05 8.24E-06 3.67E-06

4 3.67E-05 2.68E-05 1.26E-05 9.02E-06 4.51E-06

5 3.67E-05 2.68E-05 1.28E-05 9.37E-06 4.99E-06

7 3.67E-05 2.68E-05 1.29E-05 9.60E-06 5.37E-06

10 3.67E-05 2.68E-05 1.30E-05 9.65E-06 5.48E-06

15 3.67E-05 2.68E-05 1.30E-05 9.65E-06 5.49E-06

20 3.67E-05 2.68E-05 1.30E-05 9.65E-06 5.49E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 39 of 52

Table A1-7. Normalized Doses for Circular Sources with Mat = Aluminum and t = 1 hour

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 7.53E-08 1.28E-08 3.01E-09 1.03E-09 2.40E-10

0.25 2.01E-07 6.07E-08 1.81E-08 6.68E-09 1.72E-09

0.50 3.02E-07 1.46E-07 5.86E-08 2.41E-08 6.23E-09

1 3.97E-07 2.54E-07 1.40E-07 7.22E-08 2.14E-08

2 4.88E-07 3.62E-07 2.50E-07 1.62E-07 6.86E-08

3 5.41E-07 4.24E-07 3.17E-07 2.27E-07 1.16E-07

4 5.78E-07 4.68E-07 3.64E-07 2.76E-07 1.57E-07

5 6.06E-07 5.03E-07 4.00E-07 3.15E-07 1.93E-07

7 6.50E-07 5.53E-07 4.56E-07 3.75E-07 2.50E-07

10 6.95E-07 6.06E-07 5.17E-07 4.36E-07 3.13E-07

15 7.46E-07 6.65E-07 5.83E-07 5.07E-07 3.86E-07

20 7.81E-07 7.05E-07 6.29E-07 5.56E-07 4.37E-07

50 8.89E-07 8.28E-07 7.67E-07 7.00E-07 5.91E-07

100 9.63E-07 9.13E-07 8.56E-07 7.94E-07 6.92E-07

200 1.02E-06 9.75E-07 9.23E-07 8.66E-07 7.67E-07

500 1.06E-06 1.02E-06 9.67E-07 9.10E-07 8.15E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.07E-05 1.41E-06 3.07E-07 9.37E-08 1.69E-08

0.25 2.93E-05 7.05E-06 1.84E-06 5.99E-07 1.08E-07

0.50 4.22E-05 1.73E-05 6.02E-06 2.21E-06 4.38E-07

1 4.91E-05 2.86E-05 1.43E-05 6.65E-06 1.56E-06

2 5.14E-05 3.50E-05 2.24E-05 1.35E-05 4.47E-06

3 5.17E-05 3.65E-05 2.50E-05 1.66E-05 6.79E-06

4 5.18E-05 3.69E-05 2.59E-05 1.80E-05 8.21E-06

5 5.18E-05 3.71E-05 2.63E-05 1.86E-05 9.02E-06

7 5.18E-05 3.71E-05 2.66E-05 1.90E-05 9.69E-06

10 5.18E-05 3.72E-05 2.66E-05 1.91E-05 9.94E-06

15 5.18E-05 3.72E-05 2.66E-05 1.91E-05 9.99E-06

20 5.18E-05 3.72E-05 2.66E-05 1.91E-05 9.99E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 40 of 52

Table A1-8. Normalized Doses for Circular Sources with Mat = Aluminum and t = 1 day

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 6.04E-08 9.36E-09 2.23E-09 6.90E-10 1.82E-10

0.25 1.58E-07 4.56E-08 1.28E-08 4.51E-09 1.08E-09

0.50 2.39E-07 1.08E-07 4.14E-08 1.56E-08 4.01E-09

1 3.14E-07 1.87E-07 9.87E-08 4.92E-08 1.47E-08

2 3.84E-07 2.68E-07 1.76E-07 1.12E-07 4.58E-08

3 4.24E-07 3.14E-07 2.24E-07 1.57E-07 7.85E-08

4 4.51E-07 3.47E-07 2.59E-07 1.91E-07 1.07E-07

5 4.73E-07 3.71E-07 2.86E-07 2.18E-07 1.32E-07

7 5.05E-07 4.08E-07 3.25E-07 2.60E-07 1.72E-07

10 5.38E-07 4.46E-07 3.67E-07 3.03E-07 2.15E-07

15 5.74E-07 4.88E-07 4.13E-07 3.50E-07 2.66E-07

20 6.00E-07 5.18E-07 4.46E-07 3.84E-07 3.01E-07

50 6.77E-07 6.06E-07 5.38E-07 4.83E-07 4.05E-07

100 7.28E-07 6.62E-07 5.98E-07 5.47E-07 4.70E-07

200 7.66E-07 7.04E-07 6.42E-07 5.93E-07 5.18E-07

500 7.89E-07 7.28E-07 6.67E-07 6.18E-07 5.44E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.15E-05 1.43E-06 2.96E-07 8.68E-08 1.24E-08

0.25 2.95E-05 7.12E-06 1.73E-06 5.18E-07 7.47E-08

0.50 4.00E-05 1.65E-05 5.52E-06 1.89E-06 2.88E-07

1 4.47E-05 2.53E-05 1.23E-05 5.40E-06 1.01E-06

2 4.60E-05 2.92E-05 1.76E-05 9.90E-06 2.71E-06

3 4.61E-05 2.99E-05 1.89E-05 1.15E-05 3.84E-06

4 4.61E-05 3.01E-05 1.92E-05 1.21E-05 4.43E-06

5 4.61E-05 3.01E-05 1.94E-05 1.23E-05 4.73E-06

7 4.61E-05 3.01E-05 1.95E-05 1.24E-05 4.95E-06

10 4.61E-05 3.01E-05 1.95E-05 1.25E-05 5.01E-06

15 4.61E-05 3.01E-05 1.95E-05 1.25E-05 5.01E-06

20 4.61E-05 3.01E-05 1.95E-05 1.25E-05 5.01E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 41 of 52

Table A1-9. Normalized Doses for Circular Sources with Mat = Aluminum and t = 1 week

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 5.96E-08 8.93E-09 2.24E-09 7.01E-10 1.58E-10

0.25 1.55E-07 4.46E-08 1.26E-08 4.55E-09 1.09E-09

0.50 2.34E-07 1.06E-07 4.09E-08 1.68E-08 4.09E-09

1 3.08E-07 1.85E-07 9.93E-08 5.10E-08 1.55E-08

2 3.78E-07 2.67E-07 1.77E-07 1.15E-07 4.83E-08

3 4.18E-07 3.15E-07 2.27E-07 1.63E-07 8.06E-08

4 4.46E-07 3.47E-07 2.63E-07 1.98E-07 1.10E-07

5 4.67E-07 3.72E-07 2.91E-07 2.26E-07 1.35E-07

7 4.99E-07 4.09E-07 3.32E-07 2.68E-07 1.76E-07

10 5.33E-07 4.48E-07 3.74E-07 3.13E-07 2.22E-07

15 5.70E-07 4.92E-07 4.22E-07 3.63E-07 2.74E-07

20 5.97E-07 5.22E-07 4.55E-07 3.98E-07 3.09E-07

50 6.75E-07 6.14E-07 5.53E-07 5.01E-07 4.18E-07

100 7.30E-07 6.73E-07 6.16E-07 5.67E-07 4.88E-07

200 7.72E-07 7.17E-07 6.63E-07 6.14E-07 5.38E-07

500 7.97E-07 7.43E-07 6.90E-07 6.42E-07 5.67E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.17E-05 1.33E-06 2.10E-07 4.93E-08 5.58E-09

0.25 2.71E-05 6.16E-06 1.17E-06 3.11E-07 3.19E-08

0.50 3.40E-05 1.29E-05 3.54E-06 1.11E-06 1.25E-07

1 3.65E-05 1.77E-05 7.39E-06 3.04E-06 4.38E-07

2 3.69E-05 1.94E-05 9.79E-06 5.05E-06 1.08E-06

3 3.69E-05 1.96E-05 1.02E-05 5.55E-06 1.40E-06

4 3.69E-05 1.97E-05 1.03E-05 5.67E-06 1.52E-06

5 3.69E-05 1.97E-05 1.03E-05 5.70E-06 1.56E-06

7 3.69E-05 1.97E-05 1.03E-05 5.71E-06 1.58E-06

10 3.69E-05 1.97E-05 1.03E-05 5.71E-06 1.59E-06

15 3.69E-05 1.97E-05 1.03E-05 5.71E-06 1.59E-06

20 3.69E-05 1.97E-05 1.03E-05 5.72E-06 1.59E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 42 of 52

Table A1-10. Normalized Doses for Circular Sources with Mat = Aluminum and t = 1 month

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 6.49E-08 1.03E-08 2.74E-09 8.37E-10 2.11E-10

0.25 1.75E-07 5.11E-08 1.51E-08 5.43E-09 1.15E-09

0.50 2.63E-07 1.21E-07 4.89E-08 1.98E-08 4.63E-09

1 3.46E-07 2.11E-07 1.16E-07 5.99E-08 1.78E-08

2 4.22E-07 3.02E-07 2.06E-07 1.33E-07 5.51E-08

3 4.68E-07 3.56E-07 2.61E-07 1.87E-07 9.31E-08

4 4.99E-07 3.93E-07 3.01E-07 2.27E-07 1.26E-07

5 5.23E-07 4.22E-07 3.33E-07 2.60E-07 1.56E-07

7 5.59E-07 4.63E-07 3.79E-07 3.07E-07 2.03E-07

10 5.98E-07 5.06E-07 4.27E-07 3.57E-07 2.55E-07

15 6.40E-07 5.54E-07 4.81E-07 4.13E-07 3.14E-07

20 6.69E-07 5.88E-07 5.17E-07 4.52E-07 3.56E-07

50 7.58E-07 6.88E-07 6.26E-07 5.67E-07 4.79E-07

100 8.18E-07 7.54E-07 6.97E-07 6.41E-07 5.58E-07

200 8.65E-07 8.04E-07 7.50E-07 6.96E-07 6.15E-07

500 8.94E-07 8.35E-07 7.82E-07 7.29E-07 6.48E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.16E-05 1.33E-06 2.08E-07 5.66E-08 7.23E-09

0.25 2.73E-05 6.20E-06 1.18E-06 3.33E-07 4.03E-08

0.50 3.45E-05 1.31E-05 3.63E-06 1.18E-06 1.50E-07

1 3.71E-05 1.83E-05 7.73E-06 3.26E-06 5.12E-07

2 3.77E-05 2.03E-05 1.04E-05 5.54E-06 1.30E-06

3 3.77E-05 2.05E-05 1.09E-05 6.19E-06 1.72E-06

4 3.77E-05 2.06E-05 1.11E-05 6.37E-06 1.90E-06

5 3.77E-05 2.06E-05 1.11E-05 6.42E-06 1.96E-06

7 3.77E-05 2.06E-05 1.11E-05 6.45E-06 2.00E-06

10 3.77E-05 2.06E-05 1.11E-05 6.45E-06 2.01E-06

15 3.77E-05 2.06E-05 1.11E-05 6.45E-06 2.01E-06

20 3.77E-05 2.06E-05 1.11E-05 6.45E-06 2.01E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 43 of 52

Table A1-11. Normalized Doses for Circular Sources with Mat = Aluminum and t = 6 months

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 7.34E-08 1.19E-08 2.92E-09 8.49E-10 2.75E-10

0.25 1.92E-07 5.69E-08 1.64E-08 5.13E-09 1.27E-09

0.50 2.89E-07 1.35E-07 5.06E-08 1.84E-08 4.64E-09

1 3.78E-07 2.30E-07 1.18E-07 5.67E-08 1.74E-08

2 4.62E-07 3.26E-07 2.11E-07 1.31E-07 5.45E-08

3 5.08E-07 3.81E-07 2.71E-07 1.85E-07 9.22E-08

4 5.40E-07 4.20E-07 3.12E-07 2.27E-07 1.26E-07

5 5.64E-07 4.51E-07 3.46E-07 2.60E-07 1.56E-07

7 6.02E-07 4.94E-07 3.95E-07 3.10E-07 2.03E-07

10 6.41E-07 5.40E-07 4.47E-07 3.64E-07 2.55E-07

15 6.84E-07 5.92E-07 5.03E-07 4.23E-07 3.15E-07

20 7.15E-07 6.27E-07 5.42E-07 4.64E-07 3.57E-07

50 8.05E-07 7.33E-07 6.57E-07 5.82E-07 4.80E-07

100 8.66E-07 8.02E-07 7.30E-07 6.59E-07 5.58E-07

200 9.12E-07 8.53E-07 7.83E-07 7.13E-07 6.15E-07

500 9.39E-07 8.82E-07 8.12E-07 7.43E-07 6.46E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.12E-05 1.20E-06 1.56E-07 4.12E-08 7.55E-09

0.25 2.55E-05 5.42E-06 8.71E-07 2.49E-07 4.39E-08

0.50 3.22E-05 1.10E-05 2.65E-06 8.98E-07 1.71E-07

1 3.48E-05 1.56E-05 6.00E-06 2.72E-06 6.16E-07

2 3.57E-05 1.80E-05 9.14E-06 5.38E-06 1.74E-06

3 3.58E-05 1.85E-05 1.01E-05 6.52E-06 2.56E-06

4 3.58E-05 1.86E-05 1.04E-05 6.96E-06 3.03E-06

5 3.58E-05 1.87E-05 1.05E-05 7.14E-06 3.28E-06

7 3.58E-05 1.87E-05 1.05E-05 7.26E-06 3.48E-06

10 3.58E-05 1.87E-05 1.06E-05 7.28E-06 3.53E-06

15 3.58E-05 1.87E-05 1.06E-05 7.28E-06 3.54E-06

20 3.58E-05 1.87E-05 1.06E-05 7.28E-06 3.54E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 44 of 52

Table A1-12. Normalized Doses for Circular Sources with Mat = Aluminum and t = 1 year

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 7.26E-08 1.16E-08 2.71E-09 8.35E-10 1.63E-10

0.25 1.90E-07 5.62E-08 1.59E-08 5.19E-09 1.17E-09

0.50 2.86E-07 1.32E-07 4.96E-08 1.87E-08 5.04E-09

1 3.75E-07 2.26E-07 1.18E-07 5.80E-08 1.80E-08

2 4.58E-07 3.21E-07 2.10E-07 1.33E-07 5.61E-08

3 5.04E-07 3.77E-07 2.69E-07 1.89E-07 9.48E-08

4 5.36E-07 4.16E-07 3.12E-07 2.32E-07 1.29E-07

5 5.61E-07 4.46E-07 3.46E-07 2.65E-07 1.60E-07

7 5.98E-07 4.91E-07 3.96E-07 3.17E-07 2.07E-07

10 6.37E-07 5.37E-07 4.47E-07 3.71E-07 2.61E-07

15 6.81E-07 5.89E-07 5.04E-07 4.32E-07 3.22E-07

20 7.12E-07 6.25E-07 5.44E-07 4.74E-07 3.64E-07

50 8.06E-07 7.32E-07 6.62E-07 5.96E-07 4.90E-07

100 8.68E-07 8.02E-07 7.36E-07 6.74E-07 5.70E-07

200 9.15E-07 8.55E-07 7.92E-07 7.32E-07 6.27E-07

500 9.44E-07 8.84E-07 8.23E-07 7.63E-07 6.58E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.08E-05 1.17E-06 1.54E-07 4.32E-08 7.16E-09

0.25 2.53E-05 5.37E-06 8.83E-07 2.73E-07 5.65E-08

0.50 3.29E-05 1.12E-05 2.78E-06 1.00E-06 2.23E-07

1 3.65E-05 1.68E-05 6.70E-06 3.12E-06 8.21E-07

2 3.78E-05 2.02E-05 1.10E-05 6.67E-06 2.42E-06

3 3.80E-05 2.10E-05 1.25E-05 8.48E-06 3.78E-06

4 3.80E-05 2.13E-05 1.30E-05 9.29E-06 4.64E-06

5 3.80E-05 2.14E-05 1.32E-05 9.66E-06 5.13E-06

7 3.80E-05 2.14E-05 1.34E-05 9.90E-06 5.53E-06

10 3.80E-05 2.14E-05 1.34E-05 9.95E-06 5.64E-06

15 3.80E-05 2.14E-05 1.34E-05 9.96E-06 5.65E-06

20 3.80E-05 2.14E-05 1.34E-05 9.96E-06 5.65E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 45 of 52

Table A1-13. Normalized Doses for Circular Sources with Mat = Iron and t = 1 hour

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 1.37 2

0.10 9.28E-08 1.51E-08 3.79E-09 1.31E-09 6.70E-10 2.23E-10

0.25 2.25E-07 7.15E-08 2.18E-08 7.72E-09 3.85E-09 1.77E-09

0.50 3.29E-07 1.64E-07 6.79E-08 2.81E-08 1.48E-08 6.78E-09

1 4.27E-07 2.75E-07 1.58E-07 8.23E-08 5.05E-08 2.54E-08

2 5.22E-07 3.87E-07 2.72E-07 1.78E-07 1.26E-07 7.56E-08

3 5.78E-07 4.53E-07 3.42E-07 2.46E-07 1.88E-07 1.25E-07

4 6.18E-07 4.98E-07 3.91E-07 2.97E-07 2.38E-07 1.68E-07

5 6.48E-07 5.33E-07 4.29E-07 3.36E-07 2.78E-07 2.05E-07

7 6.94E-07 5.86E-07 4.85E-07 3.96E-07 3.39E-07 2.64E-07

10 7.42E-07 6.41E-07 5.45E-07 4.59E-07 4.04E-07 3.30E-07

15 7.96E-07 7.02E-07 6.11E-07 5.30E-07 4.76E-07 4.04E-07

20 8.34E-07 7.45E-07 6.56E-07 5.79E-07 5.27E-07 4.55E-07

50 9.50E-07 8.72E-07 7.93E-07 7.24E-07 6.77E-07 6.11E-07

100 1.03E-06 9.58E-07 8.82E-07 8.18E-07 7.73E-07 7.12E-07

200 1.09E-06 1.02E-06 9.51E-07 8.90E-07 8.45E-07 7.87E-07

500 1.13E-06 1.07E-06 9.94E-07 9.35E-07 8.91E-07 8.33E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.21E-05 1.62E-06 3.57E-07 1.08E-07 2.02E-08

0.25 3.25E-05 8.06E-06 2.10E-06 6.92E-07 1.25E-07

0.50 4.62E-05 1.93E-05 6.81E-06 2.53E-06 4.87E-07

1 5.36E-05 3.16E-05 1.60E-05 7.54E-06 1.74E-06

2 5.61E-05 3.85E-05 2.48E-05 1.50E-05 4.99E-06

3 5.65E-05 4.02E-05 2.77E-05 1.85E-05 7.52E-06

4 5.65E-05 4.06E-05 2.87E-05 1.99E-05 9.04E-06

5 5.65E-05 4.08E-05 2.91E-05 2.06E-05 9.92E-06

7 5.65E-05 4.09E-05 2.94E-05 2.11E-05 1.06E-05

10 5.65E-05 4.09E-05 2.95E-05 2.12E-05 1.09E-05

15 5.65E-05 4.09E-05 2.95E-05 2.12E-05 1.10E-05

20 5.65E-05 4.09E-05 2.95E-05 2.12E-05 1.10E-05
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 46 of 52

Table A1-14. Normalized Doses for Circular Sources with Mat = Iron and t = 1 day

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 1.37 2

0.10 7.37E-08 1.15E-08 2.67E-09 8.79E-10 4.45E-10 1.77E-10

0.25 1.82E-07 5.44E-08 1.51E-08 5.05E-09 2.59E-09 1.06E-09

0.50 2.68E-07 1.23E-07 4.71E-08 1.83E-08 9.61E-09 4.27E-09

1 3.46E-07 2.08E-07 1.11E-07 5.41E-08 3.26E-08 1.57E-08

2 4.20E-07 2.91E-07 1.92E-07 1.21E-07 8.47E-08 4.83E-08

3 4.61E-07 3.39E-07 2.42E-07 1.68E-07 1.27E-07 8.11E-08

4 4.91E-07 3.72E-07 2.77E-07 2.04E-07 1.61E-07 1.10E-07

5 5.14E-07 3.96E-07 3.05E-07 2.31E-07 1.88E-07 1.35E-07

7 5.46E-07 4.34E-07 3.45E-07 2.73E-07 2.29E-07 1.75E-07

10 5.80E-07 4.73E-07 3.86E-07 3.17E-07 2.73E-07 2.20E-07

15 6.19E-07 5.16E-07 4.33E-07 3.66E-07 3.23E-07 2.70E-07

20 6.45E-07 5.45E-07 4.64E-07 4.00E-07 3.57E-07 3.05E-07

50 7.27E-07 6.33E-07 5.59E-07 4.98E-07 4.57E-07 4.07E-07

100 7.82E-07 6.90E-07 6.19E-07 5.61E-07 5.21E-07 4.72E-07

200 8.24E-07 7.33E-07 6.64E-07 6.06E-07 5.66E-07 5.19E-07

500 8.48E-07 7.58E-07 6.89E-07 6.32E-07 5.92E-07 5.45E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.30E-05 1.67E-06 3.39E-07 1.02E-07 1.34E-08

0.25 3.28E-05 8.12E-06 1.99E-06 6.03E-07 8.55E-08

0.50 4.41E-05 1.86E-05 6.28E-06 2.17E-06 3.27E-07

1 4.92E-05 2.81E-05 1.37E-05 6.09E-06 1.13E-06

2 5.06E-05 3.24E-05 1.95E-05 1.10E-05 2.98E-06

3 5.07E-05 3.32E-05 2.09E-05 1.28E-05 4.19E-06

4 5.07E-05 3.34E-05 2.13E-05 1.34E-05 4.83E-06

5 5.07E-05 3.34E-05 2.15E-05 1.36E-05 5.15E-06

7 5.07E-05 3.34E-05 2.16E-05 1.38E-05 5.39E-06

10 5.07E-05 3.34E-05 2.16E-05 1.38E-05 5.46E-06

15 5.07E-05 3.34E-05 2.16E-05 1.38E-05 5.47E-06

20 5.07E-05 3.34E-05 2.16E-05 1.38E-05 5.47E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 47 of 52

Table A1-15. Normalized Doses for Circular Sources with Mat = Iron and t = 1 week

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 1.37 2

0.10 7.31E-08 1.13E-08 2.51E-09 8.27E-10 3.84E-10 1.67E-10

0.25 1.77E-07 5.23E-08 1.51E-08 5.11E-09 2.41E-09 1.06E-09

0.50 2.58E-07 1.21E-07 4.83E-08 1.88E-08 9.75E-09 4.48E-09

1 3.36E-07 2.04E-07 1.12E-07 5.62E-08 3.43E-08 1.65E-08

2 4.08E-07 2.87E-07 1.94E-07 1.24E-07 8.66E-08 5.09E-08

3 4.49E-07 3.35E-07 2.46E-07 1.73E-07 1.31E-07 8.62E-08

4 4.78E-07 3.69E-07 2.81E-07 2.09E-07 1.65E-07 1.16E-07

5 5.01E-07 3.95E-07 3.09E-07 2.37E-07 1.94E-07 1.42E-07

7 5.35E-07 4.33E-07 3.51E-07 2.80E-07 2.37E-07 1.83E-07

10 5.69E-07 4.73E-07 3.94E-07 3.26E-07 2.82E-07 2.27E-07

15 6.09E-07 5.17E-07 4.41E-07 3.76E-07 3.34E-07 2.79E-07

20 6.37E-07 5.48E-07 4.73E-07 4.10E-07 3.69E-07 3.15E-07

50 7.22E-07 6.41E-07 5.73E-07 5.13E-07 4.75E-07 4.23E-07

100 7.78E-07 7.02E-07 6.36E-07 5.79E-07 5.42E-07 4.91E-07

200 8.22E-07 7.46E-07 6.82E-07 6.27E-07 5.90E-07 5.41E-07

500 8.48E-07 7.72E-07 7.09E-07 6.55E-07 6.18E-07 5.69E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.34E-05 1.52E-06 2.30E-07 6.07E-08 6.12E-09

0.25 3.03E-05 7.00E-06 1.31E-06 3.54E-07 3.66E-08

0.50 3.78E-05 1.44E-05 4.00E-06 1.25E-06 1.43E-07

1 4.05E-05 1.97E-05 8.27E-06 3.39E-06 4.85E-07

2 4.10E-05 2.16E-05 1.09E-05 5.59E-06 1.19E-06

3 4.10E-05 2.18E-05 1.13E-05 6.14E-06 1.53E-06

4 4.10E-05 2.18E-05 1.14E-05 6.27E-06 1.65E-06

5 4.10E-05 2.18E-05 1.14E-05 6.31E-06 1.70E-06

7 4.10E-05 2.18E-05 1.14E-05 6.32E-06 1.72E-06

10 4.10E-05 2.18E-05 1.14E-05 6.32E-06 1.72E-06

15 4.10E-05 2.18E-05 1.14E-05 6.32E-06 1.72E-06

20 4.10E-05 2.18E-05 1.14E-05 6.32E-06 1.72E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 48 of 52

Table A1-16. Normalized Doses for Circular Sources with Mat = Iron and t = 1 month

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 1.37 2

0.10 8.09E-08 1.29E-08 3.05E-09 1.04E-09 5.02E-10 2.02E-10

0.25 1.99E-07 6.02E-08 1.78E-08 6.06E-09 3.17E-09 1.29E-09

0.50 2.90E-07 1.38E-07 5.57E-08 2.20E-08 1.18E-08 5.42E-09

1 3.76E-07 2.33E-07 1.31E-07 6.60E-08 3.91E-08 2.02E-08

2 4.58E-07 3.28E-07 2.25E-07 1.45E-07 1.01E-07 5.92E-08

3 5.04E-07 3.82E-07 2.83E-07 2.00E-07 1.51E-07 1.00E-07

4 5.37E-07 4.21E-07 3.24E-07 2.43E-07 1.92E-07 1.35E-07

5 5.62E-07 4.49E-07 3.56E-07 2.74E-07 2.23E-07 1.65E-07

7 6.00E-07 4.93E-07 4.02E-07 3.23E-07 2.73E-07 2.13E-07

10 6.39E-07 5.37E-07 4.51E-07 3.73E-07 3.25E-07 2.65E-07

15 6.83E-07 5.86E-07 5.05E-07 4.29E-07 3.84E-07 3.25E-07

20 7.14E-07 6.20E-07 5.42E-07 4.67E-07 4.24E-07 3.67E-07

50 8.08E-07 7.23E-07 6.52E-07 5.82E-07 5.44E-07 4.90E-07

100 8.72E-07 7.90E-07 7.24E-07 6.57E-07 6.20E-07 5.69E-07

200 9.21E-07 8.41E-07 7.78E-07 7.12E-07 6.77E-07 6.27E-07

500 9.52E-07 8.72E-07 8.10E-07 7.44E-07 7.11E-07 6.62E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.33E-05 1.53E-06 2.37E-07 6.34E-08 7.35E-09

0.25 3.05E-05 7.04E-06 1.36E-06 3.80E-07 4.26E-08

0.50 3.83E-05 1.46E-05 4.15E-06 1.34E-06 1.60E-07

1 4.12E-05 2.03E-05 8.68E-06 3.64E-06 5.56E-07

2 4.18E-05 2.24E-05 1.16E-05 6.13E-06 1.40E-06

3 4.18E-05 2.27E-05 1.22E-05 6.83E-06 1.87E-06

4 4.18E-05 2.27E-05 1.23E-05 7.02E-06 2.06E-06

5 4.18E-05 2.27E-05 1.23E-05 7.08E-06 2.13E-06

7 4.18E-05 2.27E-05 1.24E-05 7.11E-06 2.17E-06

10 4.18E-05 2.28E-05 1.24E-05 7.11E-06 2.18E-06

15 4.18E-05 2.28E-05 1.24E-05 7.11E-06 2.18E-06

20 4.18E-05 2.28E-05 1.24E-05 7.11E-06 2.18E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 49 of 52

Table A1-17. Normalized Doses for Circular Sources with Mat = Iron and t = 6 months

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 1.37 2

0.10 8.51E-08 1.44E-08 3.31E-09 9.51E-10 4.58E-10 1.97E-10

0.25 2.11E-07 6.62E-08 1.86E-08 5.83E-09 2.76E-09 1.22E-09

0.50 3.13E-07 1.52E-07 5.91E-08 2.09E-08 1.03E-08 4.73E-09

1 4.09E-07 2.53E-07 1.35E-07 6.27E-08 3.59E-08 1.80E-08

2 4.96E-07 3.53E-07 2.32E-07 1.39E-07 9.53E-08 5.56E-08

3 5.45E-07 4.09E-07 2.92E-07 1.95E-07 1.45E-07 9.47E-08

4 5.79E-07 4.49E-07 3.35E-07 2.38E-07 1.85E-07 1.29E-07

5 6.04E-07 4.78E-07 3.68E-07 2.71E-07 2.18E-07 1.59E-07

7 6.43E-07 5.24E-07 4.18E-07 3.21E-07 2.69E-07 2.07E-07

10 6.83E-07 5.70E-07 4.70E-07 3.74E-07 3.23E-07 2.60E-07

15 7.28E-07 6.22E-07 5.26E-07 4.33E-07 3.83E-07 3.21E-07

20 7.60E-07 6.58E-07 5.66E-07 4.74E-07 4.25E-07 3.63E-07

50 8.56E-07 7.66E-07 6.84E-07 5.94E-07 5.46E-07 4.86E-07

100 9.20E-07 8.36E-07 7.58E-07 6.70E-07 6.23E-07 5.65E-07

200 9.70E-07 8.88E-07 8.12E-07 7.25E-07 6.79E-07 6.21E-07

500 9.99E-07 9.18E-07 8.41E-07 7.57E-07 7.10E-07 6.53E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.27E-05 1.36E-06 1.72E-07 4.70E-08 8.18E-09

0.25 2.84E-05 6.11E-06 9.73E-07 2.84E-07 5.01E-08

0.50 3.56E-05 1.23E-05 3.00E-06 1.03E-06 1.96E-07

1 3.85E-05 1.73E-05 6.73E-06 3.05E-06 6.94E-07

2 3.94E-05 1.99E-05 1.01E-05 5.97E-06 1.93E-06

3 3.95E-05 2.05E-05 1.11E-05 7.20E-06 2.84E-06

4 3.95E-05 2.06E-05 1.15E-05 7.69E-06 3.35E-06

5 3.95E-05 2.07E-05 1.16E-05 7.89E-06 3.62E-06

7 3.95E-05 2.07E-05 1.17E-05 8.01E-06 3.82E-06

10 3.95E-05 2.07E-05 1.17E-05 8.04E-06 3.87E-06

15 3.95E-05 2.07E-05 1.17E-05 8.04E-06 3.88E-06

20 3.95E-05 2.07E-05 1.17E-05 8.04E-06 3.88E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 50 of 52

Table A1-18. Normalized Doses for Circular Sources with Mat = Iron and t = 1 year

Gamma

Radius (m) Height (m)

0.1 0.3 0.6 1 1.37 2

0.10 8.50E-08 1.39E-08 3.48E-09 9.33E-10 4.53E-10 1.75E-10

0.25 2.09E-07 6.54E-08 1.90E-08 6.07E-09 2.95E-09 1.34E-09

0.50 3.09E-07 1.51E-07 5.90E-08 2.12E-08 1.10E-08 4.91E-09

1 4.05E-07 2.53E-07 1.35E-07 6.41E-08 3.68E-08 1.82E-08

2 4.92E-07 3.53E-07 2.32E-07 1.43E-07 9.70E-08 5.65E-08

3 5.41E-07 4.09E-07 2.93E-07 2.00E-07 1.47E-07 9.67E-08

4 5.75E-07 4.49E-07 3.37E-07 2.43E-07 1.88E-07 1.32E-07

5 6.01E-07 4.80E-07 3.69E-07 2.77E-07 2.21E-07 1.61E-07

7 6.41E-07 5.25E-07 4.19E-07 3.28E-07 2.72E-07 2.10E-07

10 6.81E-07 5.73E-07 4.70E-07 3.83E-07 3.27E-07 2.63E-07

15 7.28E-07 6.24E-07 5.28E-07 4.42E-07 3.87E-07 3.24E-07

20 7.59E-07 6.61E-07 5.68E-07 4.84E-07 4.29E-07 3.67E-07

50 8.58E-07 7.71E-07 6.87E-07 6.08E-07 5.55E-07 4.95E-07

100 9.23E-07 8.41E-07 7.63E-07 6.87E-07 6.33E-07 5.75E-07

200 9.74E-07 8.95E-07 8.19E-07 7.43E-07 6.91E-07 6.34E-07

500 1.00E-06 9.25E-07 8.50E-07 7.75E-07 7.22E-07 6.66E-07

Beta

Radius (m) Height (m)

0.1 0.3 0.6 1 2

0.10 1.23E-05 1.33E-06 1.77E-07 4.71E-08 1.07E-08

0.25 2.82E-05 6.02E-06 9.96E-07 3.07E-07 6.67E-08

0.50 3.63E-05 1.25E-05 3.14E-06 1.14E-06 2.58E-07

1 4.01E-05 1.85E-05 7.48E-06 3.51E-06 9.28E-07

2 4.15E-05 2.22E-05 1.21E-05 7.46E-06 2.71E-06

3 4.17E-05 2.31E-05 1.37E-05 9.40E-06 4.20E-06

4 4.17E-05 2.34E-05 1.43E-05 1.03E-05 5.15E-06

5 4.17E-05 2.35E-05 1.46E-05 1.07E-05 5.67E-06

7 4.17E-05 2.35E-05 1.47E-05 1.09E-05 6.11E-06

10 4.17E-05 2.35E-05 1.47E-05 1.10E-05 6.23E-06

15 4.17E-05 2.35E-05 1.47E-05 1.10E-05 6.24E-06

20 4.17E-05 2.35E-05 1.47E-05 1.10E-05 6.24E-06
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 51 of 52

Attachment 2.

Small Boat Information

The following insert containing information on the types of small boats used during 

Pacific testing operations is a reproduction of page 695 in Jane’s Fighting Ships 1983-

1984, John Moore, editor, Jane’s Publishing Company, LTD. London, England, 1983

(ISBN 07106-0774-1).
DTRA / NTPR - Standard Operating Procedures Manual

ED03- Skin Dose from External Sources

Revision No.: 2.0

Date: April 30, 2021

Page 52 of 52