ORAU Team

NIOSH Dose Reconstruction Project

Technical Basis Document for Pantex Plant – Occupational 

Medical Dose

Document Number:

ORAUT-TKBS-0013-3 

Effective Date: 08/24/2004

Revision No.: 00

Controlled Copy No.: ______

Page 1 of 15

Subject Experts: Daniel J. Strom and Jack Fix

Document Owner

Approval: Signature on File Date: 08/18/2004

Dillard B. Shipler, TBD Team Leader

Approval: Signature on File Date: 08/19/2004

Judson L. Kenoyer, Task 3 Manager

Concurrence: Signature on File Date: 08/19/2004

Richard E. Toohey, Project Director

Approval: Signature on File Date: 08/24/2004

James W. Neton, OCAS Health Science Administrator

Supersedes:

None

TABLE OF CONTENTS

Section

Record of Issue/Revisions ...................................................................................................................

Page

3

Acronyms and Abbreviations ...............................................................................................................4

3.1 Introduction................................................................................................................................. 5

3.2 Examination Frequencies............................................................................................................5

3.2.1 Frequencies from 1952 to 1982..........................................................................................5

3.2.2 Frequencies for 1982 to the Present...................................................................................5

3.3 Equipment and Techniques ........................................................................................................6

3.3.1 Photofluorography..............................................................................................................6

3.3.2 X-Ray Machines.................................................................................................................6

3.3.2.1 General Electric .........................................................................................................6

3.3.2.2 Picker ........................................................................................................................6

3.3.2.3 Universal ...................................................................................................................7

3.3.2.4 Continental ................................................................................................................7

3.3.3 Collimation before 1971......................................................................................................7

3.3.4 Specific Technique Charts..................................................................................................8

3.4 Organ Dose Calculations ............................................................................................................9

3.4.1 Conversion of ESE to Organ Dose after 1970 .................................................................. 10

3.4.2 Organ Dose before 1971.................................................................................................. 11

3.5 Uncertainty................................................................................................................................13
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3.6 Instruction Guide for Dose Reconstructors................................................................................ 13

References ........................................................................................................................................14

Glossary ............................................................................................................................................15

LIST OF TABLES

Table

3-1 1967 Pantex X-Ray techniques for three procedures ...............................................................

Page

8

3-2 Calculated ESEs for PA chest technique.................................................................................. 9

3-3 Calculated ESEs for PA lumbar spine technique.................................................................... 10

3-4 Calculated ESEs for LAT lumbar spine technique .................................................................. 10

3-5 Dose conversion factor to tissue and organs as a function of examination............................. 11

3-6 Organ dose to be assigned for each post-1970 X-ray examination ........................................ 12

3-7 Organ dose to be assigned for each pre-1971 X-ray examination.......................................... 12
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RECORD OF ISSUE/REVISIONS

ISSUE 

AUTHORIZATION 

DATE

EFFECTIVE 

DATE

REV. 

NO. DESCRIPTION

Draft 01/30/2004 00-A New technical basis document for the Pantex Plant –

Occupational Medical Dose. Initiated by Jerry Martin.

Draft 06/29/2004 00-B Incorporates internal review comments. Initiated by 

Jerry Martin. 

Draft 07/30/2004 00-C Incorporates NIOSH review comments. Initiated by 

Jerry Martin.

08/24/2004 08/24/2004 00 First approved issue. Initiated by Jerry Martin.
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 4 of 15

ACRONYMS AND ABBREVIATIONS

AP anterior-posterior

cm centimeter

EEOICPA Energy Employees Occupational Illness Compensation Program Act of 2000

ESE entrance skin exposure

Gy gray

HVL half-value layer

ICRP International Commission on Radiological Protection

in. inch

kVp kilovolt-peak

LAT lateral

mA milliampere

mAs milliampere-second

mGy milligray

mm millimeter

mR milliroentgen

NIOSH National Institute for Occupational Safety and Health

PA posterior-anterior

R roentgen

s second

SID source-to-image distance

TBD technical basis document

U.S.C. United States Code

yr year
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 5 of 15

3.1 INTRODUCTION

Technical Basis Documents (TBDs) and Site Profile Documents are general working documents that 

provide guidance concerning the preparation of dose reconstructions at particular sites or categories 

of sites. They will be revised in the event additional relevant information is obtained about the 

affected site(s). These documents may be used to assist the National Institute for Occupational 

Safety and Health (NIOSH) in the completion of the individual work required for each dose 

reconstruction.

In this document the word “facility” is used as a general term for an area, building, or group of 

buildings that served a specific purpose at a site. It does not necessarily connote an “atomic weapons 

employer facility” or a “Department of Energy facility” as defined in the Energy Employees 

Occupational Illness Compensation Program Act of 2000 [EEOICPA; 42 U.S.C. Sections 7384l(5) and 

(12)]. 

Diagnostic X-ray procedures contributed to the radiation exposure received by workers due to their 

employment at the Pantex Plant. In general, doses from these medical procedures were not included 

as part of the occupational recorded dose, although they were clearly related to occupation. NIOSH, 

in its role to reconstruct occupational dose under the EEOICPA, has classified diagnostic medical 

X-rays administered in conjunction with routine or special physical examinations required for 

employment as occupational exposures (NIOSH 2002). This TBD describes recommended options to 

conduct dose reconstruction for Pantex workers from medical X-rays administered before, during, and 

at termination of employment as a condition of employment. Background information on X-ray doses 

can be found in Technical Information Bulletin: Dose Reconstruction from Occupationally Related 

Diagnostic X-ray Procedures (ORAU 2003). This Pantex Plant TBD does not provide default values 

for lumbar spine examinations. The Technical Basis Document – Occupational Medical Dose for the 

Rocky Flats Plant (ORAU 2004) provides the method for calculating organ doses from lumbar spine 

examinations that was used in the analysis for this TBD. 

3.2 EXAMINATION FREQUENCIES

Pantex required preemployment and routine physical examinations as part of its occupational health 

and safety program. Historical files examined for selected Pantex workers contained all the historical 

radiographs and a log of the respective examinations. Based on this examination, practices have 

varied among workers, probably based on occupation, and have generally been described according 

to periods from 1952 to 1982 and from 1982 to the present.

3.2.1

From the start of U.S. Atomic Energy Commission operations at Pantex in 1952, X-ray examinations 

typically included diagnostic posterior-anterior (PA) chest X-rays. In addition, through 1982, Pantex 

required a single set of preemployment lumbar spine radiographs, both anterior-posterior (AP) and 

lateral (LAT) views, for some male employees but not for women. 

Frequencies from 1952 to 1982

Selected workers received annual chest X-rays. 

3.2.2

Beginning in 1982, the preemployment lumbar spine radiographs were generally discontinued.

Frequencies for 1982 to the Present 
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The frequency of PA chest X-rays was changed to approximately every 5 yr for selected workers 

beginning in 1982. 

3.3 EQUIPMENT AND TECHNIQUES

No records have been discovered at Pantex describing the manufacturers and models of X-ray

equipment used before 1967. Information has been obtained that requires special consideration of

Pantex worker dose for collimation and techniques used before 1971.

3.3.1

X-ray film records for long-term Pantex workers, who began work in the early 1950s, were examined

to determine if photofluorography techniques for chest X-rays were used. All the records showed 

full-size 14- by 17-in. films for all years, including 1952, 1954-1956, 1958-1959, 1962, 1964-1966, 

1968, 1970-1979, and 1982. The current X-ray technologist at Pantex says that the Plant has used 

full-size films since she began work in 1986 and that she has never seen a “small X-ray” film in a 

worker’s medical record at Pantex (Strom 2004). These observations led to the conclusion that 

photofluorography was never used at Pantex.

Photofluorography

3.3.2

There have been at least four X-ray machines at Pantex as described in the following sections. 

X-Ray Machines

3.3.2.1 General Electric 

The earliest record found of a specific X-ray machine at Pantex involved a survey of the diagnostic 

X-ray facilities at Pantex on September 26, 1967, performed by an inspector from the State of Texas. 

The inspector identified the “Control Panel Manufacturer” and “Tube Head Manufacturer and Model” 

as “General Electric.” The film was identified as “GAF Supreme” with “RADLIN T” intensifying screens

(Texas 1967). The State of Texas performed another survey of the diagnostic X-ray facilities at 

Pantex from August 13 to 18, 1970; the State inspector found a “General Electric” control panel and a 

“Profexray Model AZ Type 2” tube head. A memorandum from February 10, 1972, states: 

A survey of your X-ray machine ... has indicated serious deterioration in the output of 

the X-ray tube. The observed output was from ten to twenty times lower than the 

previous output using the same parameters. This deterioration results in poor quality 

X-rays for diagnostic uses as well as presenting an unassessable risk to patients. 

Therefore I recommend that the X-ray machine be discontinued from use until the 

malfunction has been diagnosed, corrected, and surveyed by the Safety Department

(Alexander 1972a). 

A memorandum from July 7, 1972, further explains the situation in that “[t]he chief difficulty noted is 

that low quality film was being used” (Alexander 1972b). Pantex switched back to Kodak film shortly 

thereafter. The specific impact in terms of exposure to workers can be assessed because

radiographs are available for each worker for each examination.

3.3.2.2 Picker

From approximately July 11, 1972, through 1984, a Picker X-Ray Pictronic 500 with a Picker X-Ray 

Style 2098 tube head was used. A half-value layer (HVL) measurement in 1972 showed filtrations of 

greater than 0.6 mm Al at 49 kVp and less than 1.6 mm Al at 70 kVp. In 1983, an evaluation of the 
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 7 of 15

actual number of pulses that occurred with different timer settings showed a -10% (at 0.5 s) to +33% 

(at 1/15 s) variation from the time setting. Timer problems with this machine persisted through its 

replacement in the spring of 1984. In 1983, HVL measurements were greater than 0.6 mm Al at 45 

kVp, greater than 1.6 mm Al at 70 kVp, and greater than 2.6 mm Al at 90 kVp. Kodak BB-5 Blue 

brand film and DuPont Par screens were used.

3.3.2.3 Universal

A Universal X-Ray, Inc., control panel with a Eureka X-Ray Tube Company Model Sapphire 150 tube 

head was installed between March 19 and May 25, 1984. The unit was in service through at least 

November 1, 1993. All tested parameters were apparently excellent. HVL measurements were 

greater than 0.6 mm Al at 45 kVp, greater than 1.6 mm Al at 70 kVp, and greater than 2.6 mm Al at 

90 kVp. Kodak BB-5 Blue brand film and DuPont Par screens were used through 1990, after which 

DuPont Cronex 7 film was used with Cronex Quanta III screens. The first patient entrance skin 

exposure (ESE) for PA chest radiography was measured at 4.4 mR on September 16, 1993, for a 

23-cm-thick patient at 192 cm source-to-image distance (SID) at 300 mA and 72 kVp with a large

focal spot and no grid. 

3.3.2.4 Continental

A Continental TM-50 6626.235 X-ray machine was installed between November 1, 1993, and 

November 6, 1995. On November 6, 1995, an HVL measurement of 4.8 mm Al was obtained at 

80 kVp. This machine uses photo-timing for chest films, which measures the incidence on the film 

directly, during exposure, to determine the exposure time. Output of this machine was shown by a 

certified medical physicist to vary as kVp raised to the 2.38 power between 60 and 70 kVp, and as 

kVp raised to the 2.03 power between 90 and 100 kVp (Huddleston 1995). This machine was still in 

use as of June 2004. 

3.3.3

A 1970 State of Texas survey of Pantex X-ray facilities concluded that collimation was inadequate: 

Collimation before 1971

At 40 inches target to film distance, the existing cones collimate the beam to 22 inches in 

diameter which exceeds the 15 1/2 inch diagonal length of a 10” × 12” film. At 70 inches 

target to film distance, the existing cones collimate the beam to 39 inches in diameter 

which exceeds the 22 inch diagonal length of a 14” × 17” film. For the above reasons 

none of the cones presently available should be used for either chest or extremity xrays... (Gidley 1970). 

The letter continues later, “An aluminum filter of 2.5 mm in thickness should be provided for the unit. 

Except for the thickness, the dimensions can be the same as for the existing unit” (Gidley 1970).

A 39-in.-diameter circle centered on the chest includes the gonads and the entire head for most 

adults. A 22-in.-diameter circle centered over the lumbar spine in a PA projection includes most of the 

abdomen, but probably not the thyroid, for most adults.

Evidence of collimation measurements in 1981 was located, with the conclusion that it is acceptable, 

(i.e., within 2 in. of film size). This is expected to be representative of collimation through 2004. 
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 8 of 15

The analysis for this TBD assumed that the collimation problem was corrected by January 1, 1971. 

For X-rays before 1971, in the absence of any additional information regarding filtration or collimation, 

it is assumed that: 

• For chest radiographs, tissues and organs from mid-thigh to the top of the head were exposed 

to the primary X-ray beam. 

• For lumbar spine radiographs, all abdominal tissues and organs were exposed to the primary 

X-ray beam.

3.3.4

A 1941 table of suggested X-ray techniques in Pantex Medical Department files shows that Pantex 

used a General Electric CRT 1 or CRT 2 X-ray tube operated “on full wave rectification” in the early 

days, along with “fast” film. Table 3-1 shows a transcription of 1967 X-ray technique charts. In the 

absence of other information, these techniques are assumed to have been used before the advent of 

the Continental X-Ray Equipment with photo-timing in the 1990s. 

Specific Technique Charts

Table 3-1. 1967 X-Ray techniques for three procedures.

a

 

Lumbar spine (AP)

1 s, 200 mA, 200 mAs

200 large focal spot

Bucky In

40" SID

Lumbar spine (LAT)

3 s, 200 mA, 600 mAs

200 large focal spot

Bucky In

36" SID

Chest film

0.1 s, 100 mA, 10 mAs

100 large focal spot

Measurement of

unexpanded chest

cm kVp cm kVp cm kVp

13 50 21 58 16 54

14 52 22 60 17 56

15 54 23 62 18 58

16 56 24 64 19 60

17 58 25 66 20 62

18 60 26 68 21 64

19 62 27 70 22 66

20 64 28 72 23 68

21 66 29 74 24 70

22 68 30 76 25 72

23 70 31 78 26 74

24 72 32 80 27 76

25 74 33 82 28 78

26 76 34 84 29 80

27 78 30 82

28 80 31 84

32 86

33 88

34 90

35 92

36 94

a. Copies of the charts combined in this table were obtained from Strom (2003). The 

originals were initialed on April 5, 1967, or April 10, 1967, by CS [probably Colette V. 

Stoddard per Texas (1967)]. Centimeter values are patient thickness measurements. 

Peak kilovolt (kVp) values are settings to be changed on machine.

The techniques in Table 3-1 show significant variability in patient doses. A note of Pantex instructions 

included in this reference summarized day-to-day selections as:
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• Chest - use 300 mA, 1/30 s

• AP spine - use 100 mA, 1 s (may use 200 mA for extra-heavy person or check chart)

• LAT spine - use 100 mA, 2 s (may use 200 mA for extra-heavy person or check chart)

and, for each of these examinations, set the kVp from Table 3-1 according to the size of the patient. 

These instructions also identify as “Urgent

Table 3-2 lists the ESE for PA chest radiographs. The ESE values range from 8.5 to 36.7 mR (a 

factor of 4.3). 

” for the operator to check the cone for the size of film and 

that the distance to the table is 40 in.

Table 3-2. Calculated ESEs for PA chest technique. 

Chest (PA) patient 

thickness (cm) kVp

mR/mAs 

at 12 in.

mR/mAs at 

182.88 cm (72 in.)

mR/mAs 

ESE

mR ESE 

at 10 mAs

16 54 23.08 0.64 0.85 8.5

17 56 24.96 0.69 0.93 9.3

18 58 26.92 0.75 1.02 10.2

19 60 28.96 0.80 1.11 11.1

20 62 31.08 0.86 1.20 12.0

21 64 33.28 0.92 1.31 13.1

22 66 35.56 0.99 1.41 14.1

23 68 37.92 1.05 1.53 15.3

24 70 40.36 1.12 1.65 16.5

25 72 42.88 1.19 1.77 17.7

26 74 45.49 1.26 1.91 19.1

27 76 48.18 1.34 2.05 20.5

28 78 50.95 1.42 2.19 21.9

29 80 53.80 1.49 2.35 23.5

30 82 56.74 1.58 2.51 25.1

31 84 59.76 1.66 2.68 26.8

32 86 62.87 1.75 2.86 28.6

33 88 66.06 1.84 3.05 30.5

34 90 69.34 1.93 3.25 32.5

35 92 72.69 2.02 3.45 34.5

36 94 76.14 2.11 3.67 36.7

Tables 3-3 and 3-4 list ESE values for the AP and LAT lumbar spine techniques, respectively. These 

tables show a range in ESE values of approximately a factor of 4.

3.4 ORGAN DOSE CALCULATIONS 

Organ dose calculations for workers at Pantex from 1952 to the present involve three primary 

diagnostic medical radiographic procedures administered in connection with preemployment or 

regular medical examinations: 

• PA 14- by 17-in. chest film (preemployment and annual through 1982; every 5 yr after that with 

the exception of asbestos workers (early 1980s on) and beryllium workers or beryllium 

associated workers (about 2000 on)

• AP lumbar spine film (men only; preemployment only)

• Lateral lumbar spine film (men only; preemployment only)
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 10 of 15

Table 3-3. Calculated ESEs for AP lumbar spine technique. 

Lumbar spine (AP) 

patient thickness (cm) kVp

mR/mAs at 

12 in.

mR/mAs at 

102 cm (40 in.)

mR/mAs 

ESE

mR ESE at 

200 mAs

13 50 19.56 1.76 2.79 558

14 52 21.28 1.92 3.11 623

15 54 23.08 2.08 3.46 693

16 56 24.96 2.25 3.84 768

17 58 26.92 2.42 4.25 850

18 60 28.96 2.61 4.70 939

19 62 31.08 2.80 5.17 1,035

20 64 33.28 3.00 5.69 1,138

21 66 35.56 3.20 6.25 1,250

22 68 37.92 3.41 6.85 1,370

23 70 40.36 3.63 7.50 1,499

24 72 42.88 3.86 8.20 1,639

25 74 45.49 4.09 8.95 1,789

26 76 48.18 4.34 9.76 1,951

27 78 50.95 4.59 10.63 2,126

28 80 53.80 4.84 11.57 2,313

Table 3-4. Calculated ESEs for LAT lumbar spine technique. 

Lumbar spine (LAT) 

patient thickness (cm) kVp

mR/mAs 

at 12 in.

mR/mAs at 

91.44 cm (36 in.)

mR/mAs 

ESE

mR ESE at 

600 mAs

21 58 26.92 2.99 6.42 3,849

22 60 28.96 3.22 7.13 4,277

23 62 31.08 3.45 7.90 4,743

24 64 33.28 3.70 8.75 5,250

25 66 35.56 3.95 9.67 5,804

26 68 37.92 4.21 10.68 6,406

27 70 40.36 4.48 11.77 7,063

28 72 42.88 4.76 12.96 7,778

29 74 45.49 5.05 14.26 8,556

30 76 48.18 5.35 15.67 9,404

31 78 50.95 5.66 17.21 10,328

32 80 53.80 5.98 18.89 11,334

33 82 56.74 6.30 20.72 12,432

34 84 59.76 6.64 22.72 13,629

Therefore, the analysis for this TBD evaluated only the doses from these three techniques. Other 

radiographic examinations of Pantex employees that could have occurred were generally 

nonoccupational in the sense that they were typically associated with illness or injury and were not 

part of a routine examination process. There is no indication in the examined records that other 

diagnostic radiographic examinations were routinely administered as part of the occupational medical 

program. 

3.4.1

Pantex X-ray equipment and procedures after 1970 were properly collimated, which allows conversion 

of ESE to organ dose using published conversion factors from the International Commission on 

Radiation Protection (ICRP) in Tables A2 through A9 of Publication 34 (ICRP 1982). The tables 

provide average absorbed organ doses for specific selected medical radiography procedures relative 

to an entrance air kerma without backscatter of 1 Gy for various beam qualities expressed in terms of 

HVL of aluminum. The tables do not include all organs identified in the Interactive 

RadioEpidemiological Program. Therefore, dose reconstructors should use a dose conversion 

coefficient for an included organ that is anatomically in proximity to the organ of interest to provide a 

reasonable estimate of the dose to the organ of interest. These are provided in ORAU (2003). The 

Conversion of ESE to Organ Dose after 1970
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dose reconstructor should examine doses to tissues and organs as a function of the examination in 

question, as listed in Table 3-5. The dose to the female breast is negligible from lumbar spine views, 

and the dose to the testes is negligible from AP lumbar spine and PA chest views. 

Table 3-5. Dose conversion factor to tissues and organs as a function of examination.

a

Examination

Dose conversion factor 

(mGy of absorbed dose to a tissue or organ per Gy of entrance kerma)

Projection View

SID 

(cm) HVL Thyroid Ovaries

Teste

s Lungs

Female 

breast

Uterus 

(embryo)

Active bone 

marrow

Total 

body

Lumbar spine AP 102 1.5 0.06 105 1.2 45 - 147 15 62

Lumbar spine AP 102 2 0.2 160 2.5 62 - 217 24 83

Lumbar spine AP 102 2.5 0.3 216 4.2 79 - 287 37 102

Lumbar spine AP 102 3 0.6 274 6.4 95 - 355 53 121

Lumbar spine AP 102 3.5 0.9 331 9 109 - 421 71 137

Lumbar spine AP 102 4 1.3 386 11 123 - 482 93 152

Lumbar spine Lat 102 1.5 0.01 17 0.2 6 - 11 9.4 26

Lumbar spine Lat 102 2 0.01 31 0.5 10 - 20 15 38

Lumbar spine Lat 102 2.5 0.01 47 0.8 14 - 31 22 43

Lumbar spine Lat 102 3 0.01 67 1.2 17 - 45 31 51

Lumbar spine Lat 102 3.5 0.01 87 1.8 22 - 61 43 59

Lumbar spine Lat 102 4 0.01 110 2.6 26 - 78 55 66

Chest PA 183 1.5 11 0.2 0.01 250 18 0.3 49 83

Chest PA 183 2 21 0.6 0.01 355 32 0.7 69 108

Chest PA 183 2.5 32 1 0.01 451 49 1.3 92 131

Chest PA 183 3 46 1.8 0.01 535 69 2.3 117 153

Chest PA 183 3.5 62 3.2 0.01 610 91 3 146 174

Chest PA 183 4 78 5.2 0.01 674 116 5.2 178 192

a. Entrance kerma (Gy) = ESE (R) × 0.00873 Gy/R ≈ ESE (R) × 0.01 Gy/R.

This analysis assumed that an exposure of 1 R is equivalent to a kerma of 1 rad or to 10 mGy (ORAU 

2003). The conversion to organ dose can be made easily if the beam quality is known or can 

reasonably be assumed. There is some kVp and filtration data for Pantex techniques, and an 

estimate of beam quality can be made from these data. Because absorbed organ dose increases as 

a function of HVL, the upper limit on the likely beam quality is calculated and rounded up to match the 

closest value in the tables in ICRP Publication 34 (ICRP 1982) for conservatism. The beam quality is 

assumed to be 3.5 mm Al in each case because this results in higher estimated doses to distal tissues 

and organs (shown in italicized bold text in Table 3-5). 

Entrance kerma values of 0.02 Gy (2 rads), 0.10 Gy (10 rads), and 0.0003 Gy (0.03 rad) were chosen 

for AP lumbar spine, LAT lumbar spine, and PA chest, respectively, based on patient thicknesses of 

about 26, 31, and 33 cm, respectively, which are in the upper ranges of the 1967 posted technique

charts at Pantex. From the historical information examined, there is not enough detail to make better 

assumptions, especially for periods before 1967. Because the 1967 techniques are similar to the 

1941 techniques, this analysis assumed that they are representative for all years. Table 3-6 lists 

doses obtained using these values.

3.4.2

Before 1971 and in the absence of additional information regarding filtration or collimation, Pantex 

X-ray units were apparently minimally collimated, which resulted in dose to many organs of the body 

for chest PA, AP lumbar spine, and LAT lumbar spine examinations. As such, dose conversion 

coefficients in Tables A2 through A9 of ICRP Publication 34 (ICRP 1982) are not adequate to 

calculate the dose to organs that would typically be outside a properly collimated beam (ORAU 2003). 

The recommended approach for the respective examinations is:

Organ Dose before 1971
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Table 3-6. Organ dose to be assigned for each post-1970 X-ray examination. 

Tissuea

Dose conversion factor 

(mGy to tissue/Gy entrance kerma) Examination dose (rad)

Lumbar spine

PA chest

Lumbar spine

AP LAT AP LAT PA chest 

Thyroid 0.9 0.01 62 1.80E-03 1.00E-04 1.90E-03

Ovaries 331 87 3.2 6.62E-01 8.70E-01 1.00E-04

Testes 9 1.8 0.01 1.80E-02 1.80E-02 3.00E-07

Lungs 109 22 610 2.18E-01 2.20E-01 1.83E-02

Female breast - - 91 2.70E-03

Uterus (embryo) 421 61 3 8.42E-01 6.10E-01 9.00E-05

Active bone marrow 71 43 146 1.42E-01 4.30E-01 4.40E-03

Total body 137 59 174 2.74E-01 5.90E-01 5.20E-03

Entrance skin exposure 1,000 1,000 1,000 2.00E+00 1.00E+01 3.00E-02

• For chest PA examinations, tissues and organs from the mid-thigh to the top of the worker’s 

head were exposed to the primary X-ray beam. Dose reconstructors should assign the 

maximum default organ dose (0.09 rem) from ORAU (2003, Table 4.0-1) for the chest PA 

X-ray examination to the organ of interest. 

• For lumbar spine AP and LAT radiographs, potentially many if not all abdominal tissues and 

organs were exposed to the primary X-ray beam. Guidance for the AP and LAT lumbar spine 

examinations is not included in ORAU (2003). Dose reconstructors should use guidance in 

the RFP TBD for AP and LAT lumbar spine radiographs for the period from 1952 through 1974 

because the techniques and chest PA organ doses are similar. The recommended default 

doses for the organ of interest are summarized in Table 3-7. 

Table 3-7. Organ dose for each pre-1971 X-ray examination. 

Organ

Organ dose in rad

Chest PAa AP lumbar spineb Lateral lumbar spineb

Thyroid 3.48E-02 5.00E-04 (2.96) 1.00E-04 (1.90)

Eye/brain 6.4E-3 5.00E-04 (2.96) 1.00E-04 (1.90)

Ovaries 2.5E-2 5.00E-04 (2.96) 2.25E-01 (2.10)

Urinary bladder 2.5E-2 5.00E-04 (2.96) 2.25E-01 (2.10)

Colon/rectum 2.5E-2 5.00E-04 (2.96) 2.25E-01 (2.10)

Testes 5.0E-3 2.55E-02 (3.10) 3.97E-01 (1.51)

Lung 8.38E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Liver/gall bladder/spleen 9.02E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Thymus 9.02E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Esophagus 9.02E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Stomach 9.02E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Bone surfaces 9.02E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Remainder 9.02E-2 1.22E-01 (2.53) 6.36 E-02 (2.00)

Female breast 9.80E-3 1.35E-00 (2.40) 1.37E-00 (1.90)

Uterus 2.5E-2 4.36E-01 (2.60) 1.51E-01 (2.10)

Bone marrow 1.84E-2 5.75E-02 (2.60) 1.10E-01 (2.10)

Skin 2.7E-1 1.79E-00 (2.44) 5.79E-00 (1.84)

a. Source: ORAU (2003, Table 4.0-1) 

b. Source: ORAU (2004, Table 3.4.2-2) 

Pantex workers typically received periodic chest PA X-ray examinations and only occasional lumbar 

spine examinations. The U.S. Department of Energy provides medical X-ray examination information

for each claim. 
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 13 of 15

3.5 UNCERTAINTY

Primary sources of uncertainty in occupational medical dose, which are described in ORAU (2003), 

are generically valid for the Pantex X-ray program. That analysis showed a combined uncertainty of 

±30% at 1 sigma for a single ESE or derived organ dose. 

3.6 INSTRUCTION GUIDE FOR DOSE RECONSTRUCTORS 

Pantex medical records provide the history of PA chest, AP lumbar spinal, and LAT lumbar spinal 

examinations for each claim. From the claim documentation, dose reconstructors should identify the 

tissue of interest. Using that tissue, the reconstructor should assess the dose as follows:

• After 1970, use Table 3-6 for each examination.

• Before 1971, use Table 3-7 for each examination. 

The dose to the organ or tissue of interest for each examination is in rad. 
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 14 of 15

REFERENCES

Alexander, R. E., 1972a, “X-ray Machine, 12-2 Medical,” internal memorandum to F. J. Kelly (Pantex 

Medical Director), February 10, Mason & Hanger-Silas Mason Co., Inc., Amarillo, Texas. 

Alexander, R. E., 1972b, “X-ray Installation 12-2 Medical,” internal memorandum to F. J. Kelly 

(Pantex Medical Director), July 7, Mason & Hanger-Silas Mason Co., Inc., Amarillo, Texas. 

Gidley, M. D., 1970, internal memorandum to F. J. Kelley (Pantex Medical Director), August 19, 

Mason & Hanger-Silas Mason Co., Inc., Amarillo, Texas. 

Huddleston, A. L., 1995, letter to Neil Bryson (Mason and Hanger), December 12, Texas Radiation 

Physics Associates, Inc., Dallas, Texas.

ICRP (International Commission on Radiological Protection), 1982, Protection of the Worker in 

Diagnostic Radiology, Publication 34, Pergamon Press, Oxford, England. 

NIOSH (National Institute for Occupational Safety and Health), 2002, External Dose Reconstruction 

Implementation Guidelines, OCAS-IG-001, Revision 1, Office of Compensation Analysis and 

Support, Cincinnati, Ohio.

ORAU (Oak Ridge Associated Universities), 2003, Technical Information Bulletin: Dose 

Reconstruction from Occupationally Related Diagnostic X-Ray Procedures. 

ORAUT-OTIB-0006, Revision 2, Oak Ridge, Tennessee.

ORAU (Oak Ridge Associated Universities), 2004, Technical Basis Document for the Rocky Flats 

Plant - Occupational Medical Dose, ORAUT-TKBS-0011-3, Revision 0, Oak Ridge, 

Tennessee. 

Strom, D. J., 2003, Personal communication from LaDena M. “Dea” Pierce, M.T., to Daniel J. Strom, 

July 14, 2003 (charts and instructions).

Strom, D. J., 2004, Personal communication from LaDena M. “Dea” Pierce, M.T., to Daniel J. Strom, 

June 9, 2004.

Texas (State of Texas), 1967, “X-Ray Protection Survey Report, Pantex Medical Department, Building 

12-36,” September 26, Form PHS-4495-1 (Rev. 7-65), Austin, Texas. 
Effective Date: 08/24/2004 Revision No. 00 Document No. ORAUT-TKBS-0013-3 Page 15 of 15

GLOSSARY

absorbed dose

The energy imparted per unit mass by ionizing radiation to matter at a specified point. The 

International System unit of absorbed dose is joules per kilogram. The special name for this 

unit is the gray (Gy). The previously used special unit of absorbed dose, rad, is being 

replaced by the gray (1 rad = 0.01 Gy; 1 Gy = 100 rad). 

Atomic Energy Commission

Original agency established for nuclear weapons and power production; a predecessor to the 

U.S. Department of Energy. 

anterior-posterior (AP)

Irradiation geometry in which the radiation passes from the front of a person to the back.

lateral (LAT)

Irradiation geometry in which the radiation passes from one side of a person to the other.

posterior-anterior (PA)

Irradiation geometry in which the radiation passes from the back of a person to the front.

rad

The unit for absorbed dose (1 rad = 100 erg/gram)

technique or technic

In diagnostic radiology, the combination of source-to-image distance (SID), accelerating 

potential (peak kilovoltage), tube current (milliampere), and exposure time (seconds). The last 

two parameters are often multiplied to yield the electric charge that has crossed the X-ray tube 

during the exposure, expressed in milliampere-seconds or millicoulomb. Any combination of 

time and tube current that produces a given product in milliampere-seconds will produce the 

same exposure for a fixed peak kilovoltage. 

X-ray

(1) Ionizing electromagnetic radiation of external nuclear origin. (2) An image generated by 

exposing a detector (e.g., film) to X-rays.