ORAU TEAM

Dose Reconstruction

Project for NIOSH

Oak Ridge Associated Universities I Dade Moeller I MJW Technical Services

Page 1 of 27

DOE Review Release 09/16/2009

Document Title:

Internal Dosimetry Coworker Data for the Fernald 

Environmental Management Project

Document Number: ORAUT-OTIB-0078

Revision: 00

Effective Date: 08/31/2009

Type of Document OTIB

Supersedes: None

Subject Expert(s): Robert L. Morris, Billy P. Smith, and Thomas R. LaBone

Site Expert(s): N/A

Approval: Signature on File Approval Date: 08/12/2009

Robert L. Morris, Document Owner

Concurrence: Signature on File Concurrence Date: 08/14/2009

James P. Griffin, Deputy Project Director

Concurrence: Keith A. McCartney Signature on File for Concurrence Date: 08/21/2009

Edward F. Maher, Objective 3 Manager

Concurrence: Signature on File Concurrence Date: 08/21/2009

Kate Kimpan, Project Director

Approval: Signature on File Approval Date: 08/31/2009

Larry J. Elliott, Director, OCAS

 New Total Rewrite Revision Page Change

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

REVISION AND DISCARD / DESTROY ALL COPIES OF THE PRIOR REVISION.
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 2 of 27

PUBLICATION RECORD

EFFECTIVE 

DATE

REVISION 

NUMBER DESCRIPTION

08/31/2009 00 New technical information bulletin to provide coworker data for the 

Fernald Environmental Management Project workers. Incorporates 

formal internal, NIOSH, and Advisory Board review comments. 

Training required: As determined by the Objective Manager. 

Initiated by Robert L. Morris.
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 3 of 27

TABLE OF CONTENTS

SECTION TITLE

1.0 Purpose ...................................................................................................................................

PAGE

6

2.0 Data and Method Overview......................................................................................................6

2.1 Bioassay Data Selection...............................................................................................6

2.2 Method Description.......................................................................................................7

3.0 Analysis ...................................................................................................................................7

4.0 Intake Modeling......................................................................................................................11

4.1 Assumptions...............................................................................................................11

4.2 Bioassay Fitting ..........................................................................................................11

5.0 Assigning Intakes and Doses ................................................................................................. 11

5.1 Intake Rate Summary................................................................................................. 12

5.2 Dose Assignment .......................................................................................................12

6.0 Attributions and Annotations .................................................................................................. 14

References ........................................................................................................................................15

ATTACHMENT A, COWORKER DATA FIGURES ............................................................................ 16

LIST OF TABLES

TABLE TITLE

2-1 Criteria applied to extract for uranium bioassay data................................................................

PAGE

6

3-1 Summary of uranium urinary excretion rate analyses, 1952 to 2006 ........................................ 7

5-1 Derived FEMP uranium intake rates, 1952 to 2006 for type F materials ................................. 12

5-2 Derived FEMP uranium intake rates, 1952 to 2006 for type M materials ................................ 13

5-3 Derived FEMP uranium intake rates, 1952 to 2006 for type S materials................................. 13
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 4 of 27

LIST OF FIGURES

FIGURE TITLE

A-1 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 50th percentile,

PAGE

 type F....................................................................................................................................18

A-2 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 50th percentile, 

type F.....................................................................................................................................18

A-3 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 84th percentile,

 type F....................................................................................................................................19

A-4 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 84th percentile, 

type F.....................................................................................................................................19

A-5 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 50th percentile, 

type M....................................................................................................................................19

A-6 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 50th percentile, 

type M....................................................................................................................................20

A-7 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 84th percentile, 

type M....................................................................................................................................20

A-8 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 84th percentile,

 type M...................................................................................................................................20

A-9 Predicted values versus measured results, 1/1/1952 to 12/31/1953, 50th percentile, 

type S.....................................................................................................................................21

A-10 Predicted values versus measured results, 1/1/1954 to 03/31/1956, 50th percentile, 

type S.....................................................................................................................................21

A-11 Predicted values versus measured results, 4/1/1956 to 12/31/1958, 50th percentile,

 type S....................................................................................................................................21

A-12 Predicted values versus measured results, 1/1/1959 to 12/31/1960, 50th percentile, 

type S.....................................................................................................................................22

A-13 Predicted values versus measured results, 1/1/1961 to 12/31/1965, 50th percentile, 

type S.....................................................................................................................................22

A-14 Predicted values versus measured results, 1/1/1966 to 12/31/1980, 50th percentile, 

type S.....................................................................................................................................22

A-15 Predicted values versus measured results, 1/1/1981 to 12/31/1986, 50th percentile, 

type S.....................................................................................................................................23

A-16 Predicted values versus measured results, 1/1/1987 to 12/31/1990, 50th percentile, 

type S.....................................................................................................................................23

A-17 Predicted values versus measured results, 1/1/1994 to 06/30/1997, 50th percentile, 

type S.....................................................................................................................................23

A-18 Predicted values versus measured results, 7/1/1997 to 12/31/1999, 50th percentile, 

type S.....................................................................................................................................24

A-19 Predicted values versus measured results, 1/1/2000 to 12/31/2006, 50th percentile, 

type S.....................................................................................................................................24

A-20 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 50th percentile, 

type S.....................................................................................................................................24

A-21 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 50th percentile,

 type S....................................................................................................................................25

A-22 Predicted values versus measured results, 1/1/1952 to 12/31/1953, 84th percentile, 

type S.....................................................................................................................................25

A-23 Predicted values versus measured results, 1/1/1954 to 12/31/1955, 84th percentile,

 type S....................................................................................................................................25

A-24 Predicted values versus measured results, 1/1/1956 to 12/31/1957, 84th percentile,

 type S....................................................................................................................................26
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 5 of 27

A-25 Predicted values versus measured results, 1/1/1958 to 12/31/1964, 84th percentile, 

type S.....................................................................................................................................26

A-26 Predicted values versus measured results, 1/1/1965 to 12/31/1984, 84th percentile,

 type S....................................................................................................................................26

A-27 Predicted values versus measured results, 1/1/1985 to 12/31/1990, 84th percentile, 

type S.....................................................................................................................................27

A-28 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 84th percentile,

type S.....................................................................................................................................27

A-29 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 84th percentile, 

type S.....................................................................................................................................27
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 6 of 27

1.0

Technical information bulletins (TIBs) are not official determinations made by the National Institute for 

Occupational Safety and Health (NIOSH) but are rather general working documents that provide 

historic background information and guidance to assist in 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). TIBs may be used to assist NIOSH staff in the completion of 

individual dose reconstructions.

PURPOSE

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 (DOE) facility” as defined in the Energy Employees 

Occupational Illness Compensation Program Act of 2000 [42 U.S.C. § 7384l(5) and (12)].

Some employees at DOE sites were not monitored for internal ionizing radiation exposure, or the 

monitoring records are incomplete or unavailable. In such cases, data from monitored coworkers can 

be used to estimate an individual’s possible exposure. The purpose of this OTIB is to provide 

monitored coworker information for calculating and assigning occupational internal doses to 

employees at the Fernald Environmental Management Project (FEMP) for whom no, or insufficient, 

bioassay monitoring records exist. FEMP was previously known as the Feed Materials Production 

Center.

2.0

Analysis of Coworker Bioassay Data for Internal Dose Assignment (ORAUT 2005) describes the 

general process that is used to analyze bioassay data for assigning doses to individuals based on 

coworker results. Coworker Data Exposure Profile Development (ORAUT 2004a) describes the 

approach and processes to be used to develop reasonable exposure profiles based on available 

dosimetric information for workers at DOE sites.

DATA AND METHOD OVERVIEW

2.1 BIOASSAY DATA SELECTION

The bioassay results for this analysis were obtained by extracting data from HIS-20_ORAU, a 

database of FEMP bioassay results (ORAUT 2007a). One of the database tables, 

HIS20_V_BIOASSAY, contains results for urinalyses, fecal analyses, and in vivo analyses starting in 

1952. The radionuclides in the table include 228Ac, 36Cl, 137Cs, 3

H, 210,211Pb, 210Po, 239Pu, 226,228Ra, 

90Sr, 228,230,232Th, 234,235,238U, and total uranium. The vast majority of data in the table concerns the 

uranium radionuclides. Data were extracted from the HIS20_V_BIOASSAY table using the field 

criterion in Table 2-1.

Table 2-1. Criteria applied to extract for uranium bioassay data. 

Field name Field value

TYPE_BIOASSAY URINALYSIS

NUC_NAME U-TOTAL or 238U

SAMPLE_TYPE Not equal to 10, 50, 5C, 70, VF, VR, VC

ACT_UNITS_SU μg/L

Samples with code 10 and 70 were collected before employment or reemployment to establish the 

background for the individual and as such are not appropriate for use in a study to establish intake 

potential. Samples with code 50 and 5C were collected as a part of a special study. The V series 

(VF, VR, and VE) are visitor samples and likely not representative of the typical worker. All results in 

this series were less than the minimum detectable activity.
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 7 of 27

Fifteen of the 429,338 uranium urinalysis results in ACT_UNITS-SU had units other than micrograms 

per liter; all fifteen results were discarded. Ten of these had a value for the ACTIVITY field, but no 

volume or time frame, so it was not clear if those results represented 1-liter samples or 24-hour 

samples. The other five results were isotopic samples and were excluded from the coworker study for 

expediency. The impact of discarding data from these 15 samples is judged to be negligible.

2.2 METHOD DESCRIPTION

The uranium in urine bioassay data from HIS-20_ORAU were chronologically grouped into analysis 

intervals that typically represent all of the data in a calendar quarter. During some intervals, when 

fewer results were available, the grouping represented a calendar year or a portion of a year. The 

data in each interval were fit to a lognormal distribution as described in Section 3.0. For 1991 through 

1993, fewer than 10 results per year were above the minimum detectable activity, which resulted in an 

insufficient quantity of data to generate statistics. The result of the fits resulted in excretion rates at

the 50th and 84th-percentile values at the midpoint date of the analysis interval as shown in Table 3.1.

The excretion rates for each sample were normalized to represent 24-hour samples assuming 

1,400 ml/d urine excretion, which is the daily volume that is excreted by Reference Man in 

International Commission on Radiological Protection Publication 23 (ICRP 1975). Then the intakes 

that would result in the observed excretion rates were inferred using the Integrated Modules for 

Bioassay Analysis (IMBA) computer program as described in Section 4.0.

3.0

Bioassay data statistics were generated for each analysis interval. A lognormal distribution was 

assumed [1]. After log-transforming the data, the 50th- and 84th-percentile values were determined 

for each period using the method in ORAUT (2006). The results were validated as reported by Arno 

(2007). Table 3-1 shows the statistical analysis results for uranium urinary excretion parameters.

ANALYSIS

Table 3-1. Summary of uranium urinary excretion rate analyses, 1952 to 2006. 

Analysis interval

Midpoint date of 

analysis interval

50th percentile 

(μg/d)

84th percentile 

(μg/d) 

Year 6/30/1952 15.84 62.55

Year 6/30/1953 21.76 69.74

Quarter 2/15/1954 28.92 122.41

Quarter 5/15/1954 26.17 70.14

Quarter 8/15/1954 24.72 68.50

Quarter 11/15/1954 28.59 77.98

Quarter 2/15/1955 35.49 94.21

Quarter 5/15/1955 47.62 157.91

Quarter 8/15/1955 40.05 108.75

Quarter 11/15/1955 43.01 109.90

Quarter 2/15/1956 45.00 105.58

Quarter 5/15/1956 31.80 84.17

Quarter 8/15/1956 27.28 80.02

Quarter 11/15/1956 29.54 79.45

Quarter 2/15/1957 26.08 73.71

Quarter 5/15/1957 23.94 74.78

Quarter 8/15/1957 19.92 57.86

Quarter 11/15/1957 17.15 49.31

Quarter 2/15/1958 22.27 61.46

Quarter 5/15/1958 12.13 29.02

Quarter 8/15/1958 14.08 38.78

Quarter 11/15/1958 11.32 31.55
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 8 of 27

Analysis interval

Midpoint date of 

analysis interval

50th percentile 

(μg/d)

84th percentile 

(μg/d) 

Quarter 2/15/1959 14.18 42.60

Quarter 5/15/1959 13.61 35.63

Quarter 8/15/1959 14.10 38.81

Quarter 11/15/1959 15.99 35.62

Quarter 2/15/1960 17.30 39.86

Quarter 5/15/1960 17.58 38.86

Quarter 8/15/1960 22.77 49.63

Quarter 11/15/1960 25.80 56.26

Quarter 2/15/1961 20.48 41.71

Quarter 5/15/1961 20.65 41.35

Quarter 8/15/1961 20.78 40.45

Quarter 11/15/1961 16.52 33.44

Quarter 2/15/1962 15.43 34.23

Quarter 5/15/1962 16.87 36.65

Quarter 8/15/1962 9.16 22.58

Quarter 11/15/1962 13.06 29.91

Quarter 2/15/1963 14.79 34.22

Quarter 5/15/1963 15.27 33.10

Quarter 8/15/1963 11.78 27.13

Quarter 11/15/1963 14.69 34.01

Quarter 2/15/1964 13.72 36.39

Quarter 5/15/1964 14.89 37.73

Quarter 8/15/1964 12.69 33.20

Quarter 11/15/1964 10.11 23.34

Quarter 2/15/1965 10.20 25.25

Quarter 5/15/1965 9.81 23.24

Quarter 8/15/1965 8.97 27.39

Quarter 11/15/1965 6.32 28.63

Quarter 2/15/1966 10.33 50.00

Quarter 5/15/1966 6.06 22.92

Quarter 8/15/1966 5.45 20.26

Quarter 11/15/1966 5.85 18.77

Quarter 2/15/1967 7.50 19.06

Quarter 5/15/1967 7.07 19.05

Quarter 8/15/1967 7.27 19.42

Quarter 11/15/1967 8.06 20.94

Quarter 2/15/1968 7.72 21.16

Quarter 5/15/1968 6.84 16.68

Quarter 8/15/1968 5.27 14.00

Quarter 11/15/1968 6.30 16.63

Quarter 2/15/1969 6.67 17.32

Quarter 5/15/1969 6.41 15.82

Quarter 8/15/1969 5.43 14.00

Quarter 11/15/1969 5.03 12.75

Quarter 2/15/1970 5.72 13.38

Quarter 5/15/1970 5.39 13.44

Quarter 8/15/1970 3.96 9.63

Quarter 11/15/1970 4.21 9.82

Quarter 2/15/1971 6.16 14.97

Quarter 5/15/1971 6.19 15.95

Quarter 8/15/1971 7.70 19.50

Quarter 11/15/1971 5.09 12.45

Quarter 2/15/1972 7.66 25.21
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 9 of 27

Analysis interval

Midpoint date of 

analysis interval

50th percentile 

(μg/d)

84th percentile 

(μg/d) 

Quarter 5/15/1972 4.60 13.41

Quarter 8/15/1972 5.52 13.60

Quarter 11/15/1972 6.47 15.72

Quarter 2/15/1973 6.89 17.59

Quarter 5/15/1973 6.31 15.61

Quarter 8/15/1973 7.40 21.34

Quarter 11/15/1973 7.84 23.15

Quarter 2/15/1974 7.08 17.46

Quarter 5/15/1974 6.10 14.54

Quarter 8/15/1974 6.16 15.43

Quarter 11/15/1974 7.59 20.43

Quarter 2/15/1975 7.50 17.88

Quarter 5/15/1975 7.24 18.57

Quarter 8/15/1975 5.88 15.12

Quarter 11/15/1975 7.90 18.52

Quarter 2/15/1976 7.90 19.18

Quarter 5/15/1976 6.29 15.11

Quarter 8/15/1976 6.47 14.35

Quarter 11/15/1976 5.99 15.32

Quarter 2/15/1977 6.88 18.35

Quarter 5/15/1977 6.35 13.03

Quarter 8/15/1977 5.14 11.95

Quarter 11/15/1977 5.13 11.43

Quarter 2/15/1978 5.53 12.61

Quarter 5/15/1978 6.02 13.26

Quarter 8/15/1978 5.92 12.70

Quarter 11/15/1978 6.15 13.56

Quarter 2/15/1979 7.20 14.82

Quarter 5/15/1979 6.34 14.01

Quarter 8/15/1979 5.42 13.63

Quarter 11/15/1979 5.13 13.71

Quarter 2/15/1980 6.20 15.59

Quarter 5/15/1980 5.04 12.45

Quarter 8/15/1980 6.32 14.44

Quarter 11/15/1980 6.16 13.91

Quarter 2/15/1981 3.92 10.12

Quarter 5/15/1981 3.24 8.05

Quarter 8/15/1981 4.02 10.38

Quarter 11/15/1981 4.00 10.40

Quarter 2/15/1982 4.85 11.40

Quarter 5/15/1982 4.70 12.42

Quarter 8/15/1982 5.01 11.29

Quarter 11/15/1982 5.01 12.00

Quarter 2/15/1983 5.37 12.96

Quarter 5/15/1983 4.98 13.32

Quarter 8/15/1983 4.27 11.14

Quarter 11/15/1983 4.82 12.68

Quarter 2/15/1984 4.72 11.94

Quarter 5/15/1984 5.14 13.12

Quarter 8/15/1984 5.47 13.26

Quarter 11/15/1984 5.43 13.31

Quarter 2/15/1985 6.89 12.32

Quarter 5/15/1985 5.49 11.49
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 10 of 27

Analysis interval

Midpoint date of 

analysis interval

50th percentile 

(μg/d)

84th percentile 

(μg/d) 

Quarter 8/15/1985 3.53 8.48

Quarter 11/15/1985 4.06 10.00

Quarter 2/15/1986 5.13 9.58

Quarter 5/15/1986 3.60 7.76

Quarter 8/15/1986 2.54 6.26

Quarter 11/15/1986 1.71 4.59

Quarter 2/15/1987 1.53 4.29

Quarter 5/15/1987 2.18 5.30

Quarter 8/15/1987 2.02 5.89

Quarter 11/15/1987 1.84 5.00

Quarter 2/15/1988 2.55 5.72

Quarter 5/15/1988 2.03 5.04

Quarter 8/15/1988 1.43 3.55

Quarter 11/15/1988 1.73 3.21

Quarter 2/15/1989 0.13 0.79

Quarter 5/15/1989 0.24 1.03

Quarter 8/15/1989 0.27 0.88

Quarter 11/15/1989 1.16 2.81

Quarter 2/15/1990 1.78 3.66

Quarter 5/15/1990 0.48 1.66

Quarter 8/15/1990 0.00 0.05

Year 7/1/1994 0.01 0.06

Year 7/1/1995 0.01 0.07

Year 7/1/1996 0.00 0.04

Jan–May 3/16/1997 0.00 0.02

Quarter 8/1/1997 0.02 0.09

Quarter 11/15/1997 0.02 0.09

Quarter 2/15/1998 0.03 0.09

Quarter 5/15/1998 0.02 0.08

Quarter 8/15/1998 0.01 0.07

Quarter 11/15/1998 0.01 0.07

Quarter 2/15/1999 0.01 0.06

Quarter 5/15/1999 0.02 0.06

Quarter 8/15/1999 0.02 0.08

Quarter 11/15/1999 0.03 0.10

Quarter 2/15/2000 0.02 0.09

Quarter 5/15/2000 0.02 0.10

Quarter 8/15/2000 0.02 0.11

Quarter 11/15/2000 0.03 0.11

Quarter 2/15/2001 0.03 0.11

Quarter 5/15/2001 0.05 0.19

Quarter 8/15/2001 0.06 0.20

Quarter 11/15/2001 0.05 0.17

Quarter 2/15/2002 0.04 0.13

Quarter 5/15/2002 0.05 0.15

Quarter 8/15/2002 0.05 0.17

Quarter 11/15/2002 0.06 0.12

Quarter 2/15/2003 0.03 0.11

Quarter 5/15/2003 0.05 0.17

Quarter 8/15/2003 0.04 0.14

Quarter 11/15/2003 0.06 0.14

Quarter 2/15/2004 0.04 0.11

Quarter 5/15/2004 0.05 0.15
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 11 of 27

Analysis interval

Midpoint date of 

analysis interval

50th percentile 

(μg/d)

84th percentile 

(μg/d) 

Quarter 8/15/2004 0.06 0.15

Quarter 11/15/2004 0.06 0.12

Quarter 2/15/2005 0.09 0.21

Quarter 5/15/2005 0.08 0.20

Quarter 8/15/2005 0.07 0.17

Quarter 11/15/2005 0.06 0.14

Quarter 2/15/2006 0.06 0.16

Quarter 5/15/2006 0.06 0.15

Quarter 9/1/2006 0.08 0.19

4.0

This section discusses intake modeling assumptions and intake fitting for three different material types 

of uranium compounds.

INTAKE MODELING

4.1 ASSUMPTIONS

Each result in the intake calculations was assumed to have normal distribution [2]. A uniform absolute 

error of 1 was applied to all results to assign the same weight to each result. Because of the nature of 

work at FEMP, it is possible that intakes could have been either chronic or acute. However, a series 

of acute intakes can be approximated as a chronic intake. Therefore, intakes were assumed to be 

chronic and to occur through inhalation using a default breathing rate of 1.2 m3

/hr and a 5-μm activity 

median aerodynamic diameter particle size distribution (ICRP 1995).

4.2 BIOASSAY FITTING

The IMBA computer program was used to fit the bioassay results to a series of inhalation intakes. 

Data from 1952 through 2006 were fit as a series of chronic intakes. The intake assumptions were 

based on patterns observed in the bioassay data. Periods with constant chronic intake rates were 

chosen by selecting periods where the bioassay results were similar. A new chronic intake period 

was started if the data indicated a significant and sustained change in the bioassay results. By this 

method, 1952 through 2006 was divided into multiple chronic intake periods.

Because the uranium isotopes at FEMP have long radiological half-lives and the material is retained 

in the body for long periods, excretion results are not independent. For example, an intake in the 

1950s could contribute to urinary excretion in the 1980s and later. To avoid potential underestimation 

of intakes for people who worked at FEMP for relatively short periods, each chronic intake was fit 

independently using only the bioassay results from the single intake period for type S solubility. For 

type M and F solubility, this approach was used where it was determined that earlier intake rates 

significantly biased later intake rates. This method results in a potential overestimate of intakes for 

exposures that extend through multiple assumed intake periods. Uranium urinalysis results were 

analyzed with IMBA to derive intake rates for 1952 to 2006. Attachment A contains the plots that 

compare predicted uranium bioassay results based on IMBA-derived uranium intake rates with the 

measured urine results. 

5.0

This section describes the derived intake rates and provides guidance for assigning doses. For each 

intake period below, the geometric standard deviations (GSDs) were determined by dividing the 

84th-percentile intake rates by the 50th-percentile rates. For the calculation of doses to individuals 

from bioassay data, a GSD of 3 is used to account for biological variation and uncertainty in the 

ASSIGNING INTAKES AND DOSES
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 12 of 27

models (ORAUT 2007b). The same models are used for fitting the coworker data so the same 

uncertainty applies. Therefore, a minimum GSD of 3 was assigned for each of the intake periods.

5.1 INTAKE RATE SUMMARY

Multiple intake periods were fit to the derived 50th- and 84th-percentile uranium excretion data. 

Table 5-1 summarizes the 50th-percentile uranium intake rates that correspond to an intake of type F 

materials inferred from the excretion rates. Table 5-2 presents the same information for type M 

materials, and Table 5-3 presents the information for type S materials. For periods after 2006 in 

which intakes are feasible, dose reconstructors (DRs) should assume the 2006 intake rates. 

Table 5-1. Derived FEMP uranium intake rates, 1952 to 2006 for type F materials. 

From To

50th percentile 

(μg/d)

50th

percentile

(pCi/d)b GSD

1/1/1952 12/31/1952 51.2 35.0 5.02

1/1/1953 12/31/1953 86.2 58.9 3.00

1/1/1954 12/31/1954 114.2 78.0 3.00

1/1/1955 12/31/1955 156.2 106.7 3.00

1/1/1956 12/31/1956 114.2 78.0 3.00

1/1/1957 12/31/1957 86.2 58.9 3.00

1/1/1958 12/31/1959 51.2 35.0 3.00

1/1/1960 12/31/1961 79.2 54.1 3.00

1/1/1962 12/31/1964 c 51.2 82.7 3.00

1/1/1965 12/31/1984 21.4 34.6 6.44

1/1/1985 12/31/1985 21.4 34.6 3.00

1/1/1986 12/31/1990 5.40 8.7 3.10

1/1/1991 12/31/1993 5.40a 8.7 3.10a

1/1/1994 12/31/1996 0.0211 0.034 9.26

1/1/1997 12/31/2000 0.0717 0.12 4.10

1/1/2001 12/31/2006 0.205 0.33 3.00

a. For 1991 through 1993, fewer than 10 results per year were above the minimum detectable activity, which 

resulted in an insufficient quantity of data to generate a meaningful intake model. Intake rates from the 

previous interval were assumed.

b. The specific activities used to compute this column are 0.683 pCi/μg (natural uranium) for 1952 through 

1964 and 1.616 pCi/μg (2% enrichment) for 1965 to the present.

c. This period spans the transition date when the 2% enrichment assumption began in 1964 (ORAUT 2004b). 

To ensure favorability to claimants, the specific activity for 2% enrichment is assumed for the full duration 

of the period. 

5.2 DOSE ASSIGNMENT

For most cases, individual doses should be calculated from the 50th-percentile intake rates. Dose 

reconstructors should select the material type that is the most favorable to claimants and also apply 

any other recycled uranium component calculations that are required by other OTIBs and procedures. 

The lognormal distribution is selected in the Interactive Radio Epidemiological Program (IREP) with 

the calculated dose entered as Parameter 1 and the associated GSD as Parameter 2. The GSD 

relates to the intake, so it is applied to all annual doses that are determined from the intake period.
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 13 of 27

Table 5-2. Derived FEMP uranium intake rates, 1952 to 2006 for type M materials. 

From To

50th percentile 

(μg/d)

50th

percentile

(pCi/d)b GSD

1/1/1952 12/31/1952 210 143 5.02

1/1/1953 12/31/1953 322 220 3.27

1/1/1954 12/31/1954 462 316 3.00

1/1/1955 12/31/1955 672 459 3.00

1/1/1956 12/31/1956 462 316 3.00

1/1/1957 12/31/1957 322 220 3.27

1/1/1958 12/31/1959 210 143 3.00

1/1/1960 12/31/1961 322 220 3.00

1/1/1962 12/31/1964 c 210 339 3.00

1/1/1965 12/31/1985 84.0 136 3.00

1/1/1986 12/31/1990 18.2 29 3.35

1/1/1991 12/31/1993 18.2a 29 3.35a

1/1/1994 12/31/1996 0.0710 0.11 10.7

1/1/1997 12/31/2000 0.303 0.49 4.11

1/1/2001 12/31/2006 0.859 1.4 3.00

a. For 1991 through 1993, fewer than 10 results per year were above the minimum detectable activity, which 

resulted in an insufficient quantity of data to generate a meaningful intake model. Intake rates from the previous 

interval were assumed.

b. The specific activities used to compute this column are 0.683 pCi/μg (natural uranium) for 1952 through 1964 and 1.616 

pCi/μg (2% enrichment) for 1965 to the present.

c. This period spans the transition date when the 2% enrichment assumption began in 1964 (ORAUT 2004b). To ensure 

favorability to claimants, the specific activity for 2% enrichment is assumed for the full duration of the period. 

 

Table 5-3. Derived FEMP uranium intake rates, 1952 to 2006 for type S materials. 

From To

50th percentile 

(μg/d)

50th

percentile

(pCi/d)b GSD

1/1/1952 12/31/1953 8,197 5599 3.44

1/1/1954 12/31/1956 15,042 10274 3.00

1/1/1957 12/31/1957 7,140 4877 3.95

1/1/1958 12/31/1958 7,140 4877 3.00

1/1/1959 12/31/1960 7,772 5308 3.00

1/1/1961 12/31/1965 c 3,628 5863 3.00

1/1/1966 12/31/1980 3,628 5863 3.00

1/1/1981 12/31/1986 1,252 2023 3.00

1/1/1987 12/31/1990 361 583 3.16

1/1/1991 12/31/1993 361a 583 3.16a

1/1/1994 6/30/1997 1.34 2.2 18.6

7/1/1997 12/31/1999 7.29 12 3.41

1/1/2000 12/31/2006 14.0 23 3.00

a. For 1991 through 1993, fewer than 10 results per year were above the minimum detectable activity, which 

resulted in an insufficient quantity of data to generate a meaningful intake model. Intake rates from the previous 

interval were assumed..

b. The specific activities used to compute this column are 0.683 pCi/μg (natural uranium) for 1952 through 1965 and 1.616 

pCi/μg (2% enrichment) for 1966 to the present.

c. This period spans the transition date when the 2% enrichment assumption began in 1964 (ORAUT 2004b). To ensure 

favorability to claimants, the specific activity for 2% enrichment is assumed for the full duration of the period. 
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 14 of 27

6.0

Where appropriate in this document, bracketed callouts have been inserted to indicate information, 

conclusions, and recommendations provided to assist in the process of worker dose reconstruction. 

These callouts are listed here in the Attributions and Annotations section, with information to identify 

the source and justification for each associated item. Conventional References, which are provided in 

the next section of this document, link data, quotations, and other information to documents available 

for review on the Project’s Site Research Database.

ATTRIBUTIONS AND ANNOTATIONS

[1] Arno, Matthew. Oak Ridge Associated Universities Team (ORAU). Dose Reconstructor. 

June 18, 2007.

Lognormal distributions typically provide the best fit to the available data and are a distribution 

suitable for input into IREP. 

[2] Arno, Matthew. ORAU Team. Dose Reconstructor. June 18, 2007.

The error in individual bioassay results has a normal distribution because the dominant source 

of uncertainty is the counting statistics. Although the underlying group statistics have normal 

distribution, each result was treated as if it had a normal distribution to match what was done 

for analysis of an individual’s bioassay data and because the lognormal distribution of the data 

is addressed by analyzing both the 50th and 84th percentiles of the data.
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 15 of 27

REFERENCES

Arno, M., 2007, Summary Statistics Validation Report Fernald Uranium Bioassay 1952 – 2006. 

[SRDB Ref ID: 35324]

ICRP (International Commission on Radiological Protection), 1975, Reference Man: Anatomical, 

Physiological, and Metabolic Characteristics, Publication 23, Pergamon Press, Oxford, 

England.

ICRP (International Commission on Radiological Projection), 1995, Dose Coefficients for Intake of 

Radionuclides of Workers, Publication 68, Oxford, England, June.

ORAUT (Oak Ridge Associated Universities Team), 2004a, Coworker Data Exposure Profile 

Development, ORAUT-PLAN-0014, Rev. 00, Oak Ridge, Tennessee, November 24.

ORAUT (Oak Ridge Associated Universities Team), 2004b, Technical Basis Document for the Fernald 

Environmental Management Project (FEMP) – Occupational Internal Dose, ORAUT-TKBS0017-5 Rev 00, Oak Ridge, Tennessee, May 28.

ORAUT (Oak Ridge Associated Universities Team), 2005, Analysis of Coworker Bioassay Data for

Internal Dose Assignment, ORAUT-OTIB-0019, Rev. 01, Oak Ridge, Tennessee, October 7. 

ORAUT (Oak Ridge Associated Universities Team), 2006, Generating Summary Statistics for 

Coworker Bioassay Data, ORAUT-PROC-0095, Rev. 00, Oak Ridge, Tennessee, June 5.

ORAUT (Oak Ridge Associated Universities Team), 2007b, Internal Dose Reconstruction, ORAUTOTIB-0060, Rev. 00, Oak Ridge, Tennessee, February 6.

ORAUT (Oak Ridge Associated Universities Team), 2007a, HIS-20_ORAU, database, Oak Ridge, 

Tennessee. [SRDB Ref ID: 31643]
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 16 of 27

ATTACHMENT A

COWORKER DATA FIGURES

Page 1 of 12

LIST OF FIGURES

FIGURE TITLE

A-1 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 50th percentile, 

PAGE

type F.....................................................................................................................................18

A-2 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 50th percentile, 

type F.....................................................................................................................................18

A-3 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 84th percentile, 

type F.....................................................................................................................................19

A-4 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 84th percentile,

 type F....................................................................................................................................19

A-5 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 50th percentile, 

type M....................................................................................................................................19

A-6 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 50th percentile, 

type M....................................................................................................................................20

A-7 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 84th percentile, 

type M....................................................................................................................................20

A-8 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 84th percentile, 

type M....................................................................................................................................20

A-9 Predicted values versus measured results, 1/1/1952 to 12/31/1953, 50th percentile, 

type S.....................................................................................................................................21

A-10 Predicted values versus measured results, 1/1/1954 to 03/31/1956, 50th percentile, 

type S.....................................................................................................................................21

A-11 Predicted values versus measured results, 4/1/1956 to 12/31/1958, 50th percentile, 

type S.....................................................................................................................................21

A-12 Predicted values versus measured results, 1/1/1959 to 12/31/1960, 50th percentile, 

type S.....................................................................................................................................22

A-13 Predicted values versus measured results, 1/1/1961 to 12/31/1965, 50th percentile, 

type S.....................................................................................................................................22

A-14 Predicted values versus measured results, 1/1/1966 to 12/31/1980, 50th percentile, 

type S.....................................................................................................................................22

A-15 Predicted values versus measured results, 1/1/1981 to 12/31/1986, 50th percentile, 

type S.....................................................................................................................................23

A-16 Predicted values versus measured results, 1/1/1987 to 12/31/1990, 50th percentile, 

type S.....................................................................................................................................23

A-17 Predicted values versus measured results, 1/1/1994 to 06/30/1997, 50th percentile, 

type S.....................................................................................................................................23

A-18 Predicted values versus measured results, 7/1/1997 to 12/31/1999, 50th percentile, 

type S.....................................................................................................................................24

A-19 Predicted values versus measured results, 1/1/2000 to 12/31/2006, 50th percentile,

 type S....................................................................................................................................24

A-20 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 50th percentile, 

type S.....................................................................................................................................24

A-21 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 50th percentile,

type S.....................................................................................................................................25
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 17 of 27

ATTACHMENT A

COWORKER DATA FIGURES

Page 2 of 12

A-22 Predicted values versus measured results, 1/1/1952 to 12/31/1953, 84th percentile, 

type S.....................................................................................................................................25

A-23 Predicted values versus measured results, 1/1/1954 to 12/31/1955, 84th percentile,

 type S....................................................................................................................................25

A-24 Predicted values versus measured results, 1/1/1956 to 12/31/1957, 84th percentile,

 type S....................................................................................................................................26

A-25 Predicted values versus measured results, 1/1/1958 to 12/31/1964, 84th percentile,

 type S....................................................................................................................................26

A-26 Predicted values versus measured results, 1/1/1965 to 12/31/1984, 84th percentile, 

type S.....................................................................................................................................26

A-27 Predicted values versus measured results, 1/1/1985 to 12/31/1990, 84th percentile, 

type S.....................................................................................................................................27

A-28 Predicted values versus measured results, 1/1/1994 to 12/31/2006, 84th percentile, 

type S.....................................................................................................................................27

A-29 Predicted values versus measured results, 1/1/1952 to 12/31/1990, 84th percentile, 

type S.....................................................................................................................................27

This attachment shows comparisons of measured uranium urine bioassay results with predicted 

results that were calculated using IMBA-derived uranium intake rates. Blue dots represent the 

measured values that were retained for the fit. Red dots in the type S plots represent results that 

were excluded because they were outside the Type S intake period being fit. The green lines 

represent the predicted values. The figures provide the fits as follows:

• Figures A-1 and A-2 show the individual fits to the 50th-percentile excretion rates for type F 

material.

• Figures A-3 and A-4 show the individual fits to the 84th-percentile excretion rates for type F 

material.

• Figures A-5 and A-6 show the individual fits to the 50th-percentile excretion rates for type M 

material.

• Figures A-7 and A-8 show the individual fits to the 84th-percentile excretion rates for type M 

material.

• Figures A-9 through A-19 show the individual fits to the 50th-percentile excretion rates for type 

S material. Figure A-20 summarizes the results for the period 1952 through 1990.

• Figures A-21 through A-28 show the individual fits to the 84th-percentile excretion rates for 

type S material. Figure A-29 summarizes the type S results for the period 1952 through 1990.
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 18 of 27

ATTACHMENT A

COWORKER DATA FIGURES

Page 3 of 12

Figure A-1. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1990, 50th percentile, type F. 

Figure A-2. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

12/31/2006, 50th percentile, type F. 
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 19 of 27

ATTACHMENT A

COWORKER DATA FIGURES

Page 4 of 12

Figure A-3. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1990, 84th percentile, type F. 

Figure A-4. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

12/31/2006, 84th percentile, type F. 

Figure A-5. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1990, 50th percentile, type M. 
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 20 of 27

ATTACHMENT A

COWORKER DATA FIGURES

Page 5 of 12

Figure A-6. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

12/31/2006, 50th percentile, type M. 

Figure A-7. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1990, 84th percentile, type M. 

Figure A-8. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

12/31/2006, 84th percentile, type M. 
Document No. ORAUT-OTIB-0078 Revision No. 00 Effective Date: 08/31/2009 Page 21 of 27

ATTACHMENT A

COWORKER DATA FIGURES

Page 6 of 12

Figure A-9. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1953, 50th percentile, type S. Red dots represent excluded results.

Figure A-10. Predicted values (line) versus measured results (blue dots), 1/1/1954 to 

03/31/1956, 50th percentile, type S. Red dots represent excluded results.

Figure A-11. Predicted values (line) versus measured results (blue dots), 4/1/1956 to 

12/31/1958, 50th percentile, type S. Red dots represent excluded results.
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ATTACHMENT A

COWORKER DATA FIGURES

Page 7 of 12

Figure A-12. Predicted values (line) versus measured results (blue dots), 1/1/1959 to 

12/31/1960, 50th percentile, type S. Red dots represent excluded results.

Figure A-13. Predicted values (line) versus measured results (blue dots), 1/1/1961 to 

12/31/1965, 50th percentile, type S. Red dots represent excluded results.

Figure A-14. Predicted values (line) versus measured results (blue dots), 1/1/1966 to 

12/31/1980, 50th percentile, type S. Red dots represent excluded results.
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ATTACHMENT A

COWORKER DATA FIGURES

Page 8 of 12

Figure A-15. Predicted values (line) versus measured results (blue dots), 1/1/1981 to 

12/31/1986, 50th percentile, type S. Red dots represent excluded results.

Figure A-16. Predicted values (line) versus measured results (blue dots), 1/1/1987 to 

12/31/1990, 50th percentile, type S. Red dots represent excluded results.

Figure A-17. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

06/30/1997, 50th percentile, type S. Red dots represent excluded results.
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ATTACHMENT A

COWORKER DATA FIGURES

Page 9 of 12

Figure A-18. Predicted values (line) versus measured results (blue dots), 7/1/1997 to 

12/31/1999, 50th percentile, type S. Red dots represent excluded results.

Figure A-19. Predicted values (line) versus measured results (blue dots), 1/1/2000 to 

12/31/2006, 50th percentile, type S. Red dots represent excluded results.

Figure A-20. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1990, 50th percentile, type S. Red dots represent excluded results.
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ATTACHMENT A

COWORKER DATA FIGURES

Page 10 of 12

Figure A-21. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

12/31/2006, 50th percentile, type S. Red dots represent excluded results.

Figure A-22. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1953, 84th percentile, type S. Red dots represent excluded results.

Figure A-23. Predicted values (line) versus measured results (blue dots), 1/1/1954 to 

12/31/1955, 84th percentile, type S. Red dots represent excluded results.
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ATTACHMENT A

COWORKER DATA FIGURES

Page 11 of 12

Figure A-24. Predicted values (line) versus measured results (blue dots), 1/1/1956 to 

12/31/1957, 84th percentile, type S. Red dots represent excluded results.

Figure A-25. Predicted values (line) versus measured results (blue dots), 1/1/1958 to 

12/31/1964, 84th percentile, type S. Red dots represent excluded results.

Figure A-26. Predicted values (line) versus measured results (blue dots), 1/1/1965 to 

12/31/1984, 84th percentile, type S. Red dots represent excluded results.
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ATTACHMENT A

COWORKER DATA FIGURES

Page 12 of 12

Figure A-27. Predicted values (line) versus measured results (blue dots), 1/1/1985 to 

12/31/1990, 84th percentile, type S. Red dots represent excluded results.

Figure A-28. Predicted values (line) versus measured results (blue dots), 1/1/1994 to 

12/31/2006, 84th percentile, type S. 

Figure A-29. Predicted values (line) versus measured results (blue dots), 1/1/1952 to 

12/31/1990, 84th percentile, type S. Red dots represent excluded results.