REPORT TO THE ADVISORY BOARD 

ON RADIATION AND WORKER HEALTH 

National Institute of Occupational Safety and Health 

Audit of Case PIID* from the Y-12 National Security Complex 

Contract No. 200-2004-03805 

Task Order No. 4 

SCA-TR-TASK4-CNPIID* 

Prepared by 

S. Cohen & Associates 

6858 Old Dominion Road, Suite 301 

McLean, Virginia 22101 

February 2005 

NOTICE: This information is protected by Privacy Act 5 USC §552a; disclosure to any third party without 

the written consent of the individual to whom the information pertains is strictly prohibited
Document No. 

SCA-TR-TASK4-CNPIID* 

Effective Date: 

February 4, 2005 

S. Cohen & Associates:

Technical Support for the Advisory Board on 

Radiation & Worker Health Review of 

NIOSH Dose Reconstruction Program Revision No. 1 

AUDIT OF CASE PIID* FROM THE Y-12 

NATIONAL SECURITY COMPLEX

Page 2 of 17 

Task Manager: ___________________ Date: 02/04/05 

 U. Hans Behling, PhD, MPH 

Project Manager: _________________ Date: 02/04/05 

 John Mauro, PhD, CHP 

Supersedes: 

Draft Rev. 0 

Y-12 National Security Complex Case PIID* 2 S. Cohen & Associates 
TABLE OF CONTENTS 

1.0 Summary Background Information .................................................................................... 4 

1.1 Audit Objectives ..................................................................................................... 5 

1.2 Summary of Audit Findings.................................................................................... 6 

2.0 Audit of External Doses...................................................................................................... 9 

2.1 Recorded Photon Doses .......................................................................................... 9 

2.2 Missed Photon Dose ............................................................................................... 9 

2.3 Occupational Medical Exposures ......................................................................... 11 

3.0 Audit of Internal Doses..................................................................................................... 12 

4.0 CATI Report and Radiological Incidents ......................................................................... 13 

5.0 Summary Conclusions ...................................................................................................... 14 

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

Appendix A: IREP Input.............................................................................................................. 16 

Y-12 National Security Complex Case PIID* 3 S. Cohen & Associates 
1.0 SUMMARY BACKGROUND INFORMATION 

This report presents the results of an independent audit of a dose reconstruction performed by the 

National Institute of Occupational Safety and Health (NIOSH) for an energy employee who has 

worked as a PIID*, PIID*, and PIID* at the Y-12 National Security Complex since PIID*. The 

claimant’s job duties had him performing work in numerous buildings throughout the facility. 

Records suggest that the primary route of exposure to the worker was from external gamma 

radiation. The worker was provided with dosimeters to measure external exposures throughout 

the duration of his employment at Y-12. These included film badges (through PIID*), twoelement TLD dosimeters (PIID*, through PIID*), and four-element TLD dosimeters (PIID*

through the present). Periodic urine bioassay sample data indicate minimal uranium intake 

throughout his years of employment at the Y-12 complex. As a claimant-favorable assumption, 

the “hypothetical intake” described in Technical Information Bulletin: Maximum Internal Dose 

Estimates for Certain DOE Complex Claims (ORAUT-OTIB-0002, January 10, 2004), was 

assumed for the worker. In addition, the worker was assigned doses from annual occupational 

chest x-rays as part of the Y-12 medical surveillance program. 

The worker was diagnosed with cancer of the prostate gland on PIID*. Table 1 summarizes the 

results of NIOSH’s reconstruction of the doses to the energy employee’s prostate gland, which 

yielded a probability of causation (POC) of 10.26% using IREP. Because ICRP 66 and IMBA 

do not provide the means to derive the doses to the prostate gland, NIOSH used the testes as a 

claimant-favorable surrogate for the prostate for both internal and external exposures. 

Table 1. Summary of Internal/External Exposures as Estimated by NIOSH 

Appendix A 

Exposure Entry No.

Dose 

(rem) 

External Dose: 

 ▪ Photon Dosimeter Dose 1 – 3 0.368 

 ▪ Photon Missed Dose 64 – 83 1.640 

 ▪ Neutron Dosimeter Dose NA* — 

 ▪ Neutron Missed Dose NA* — 

 ▪ Occupational Medical 84 – 103 1.660 

 ▪ Onsite Ambient NC** — 

Internal Dose (Hypothetical): 4 – 63 12.151 

Total 15.819 

*NA = Not applicable 

**NC = Not considered 

Y-12 National Security Complex Case PIID* 4 S. Cohen & Associates 
1.1 AUDIT OBJECTIVES 

SC&A’s audit was performed with the following objectives: 

• To determine if NIOSH assigned doses that are consistent with monitoring 

records provided by the DOE and with the information contained in the CATI 

report 

• To determine if the dose reconstruction process complied with applicable 

procedures that include generic procedures developed by NIOSH and ORAUT, as 

well as data/procedures that are site-specific 

• In instances when procedure(s) provide more than one option or require subjective 

decisions, determine if the process is scientifically defensible and/or claimant 

favorable 

In pursuit of these objectives, a two-step process is followed in this audit. The first step of this 

audit is to independently duplicate, and therefore validate, doses derived by NIOSH. This step of 

the audit process is not only contractually mandated under Task 4, but provides NIOSH and the 

Advisory Board with a high level of assurance that the SC&A reviewer understands which 

procedures, models, site-specific data, and assumptions NIOSH used to perform its dose 

reconstruction. The second step of the audit critically evaluates whether the methods employed 

by NIOSH are technically defensible, consistent with applicable procedures, and claimant 

favorable. 

It must be noted that this audit has been conducted without the benefit of a critical review by 

SC&A under Task Order 1 of NIOSH’s Y-12 National Security Complex Site Profile 

(documents ORAUT-TKBS-0014-1, -2, -3, -4, -5, and -6). Review of these documents could 

uncover other problems or issues with the potential to affect this claim. At such time that these 

site documents are reviewed, it is recommended that dose reconstructions performed in behalf of 

the ORNL site be revisited to assess any changes caused by new information. Results of the 

current audit are expressed in terms of whether SC&A found the exposures to have been derived 

in a scientifically valid manner, and whether we found the doses to have been derived in 

compliance with applicable procedures and in a claimant-favorable manner. 

Lastly, in compliance with the Privacy Act, this report makes no reference to the claimant’s 

name, SSN, address, or any personal data that might reveal the identity of the claimant. 

Y-12 National Security Complex Case PIID* 5 S. Cohen & Associates 
1.2 SUMMARY OF AUDIT FINDINGS 

An overview of SC&A’s audit findings for Case PIID* is provided in Table 2 in the form of a 

checklist. This checklist evaluates the data collection process, information obtained from the 

CATI interview, and all methods used in the dose reconstruction. When deficiencies are 

identified by the audit, such deficiencies are further characterized with regard to their impact(s) 

by means of the following definitions: (1) low means that the deficiency has only a marginal 

impact on dose; (2) medium means that the deficiency substantially impacts the dose, but is 

unlikely to impact the compensability of the case; and (3) high means that the deficiency 

substantially impacts the dose and may also impact the compensability of the case. A full 

description of deficiencies identified in the checklist is provided in the text of the audit that 

follows. 

Y-12 National Security Complex Case PIID* 6 S. Cohen & Associates 
Table 2. Case Review Checklist __ 

CASE PIID* ASSIGNED DOSE: 15.819 rem POC: 10.26% 

Audit Response If No, Potential Significance No. Description of Technical Elements of Review YES N/A NO LOW1 MEDIUM2 HIGH3

A. REVIEW OF DATA COLLECTION: 

A.1 Did NIOSH receive all requested data for the DOE or 

AWE site from any relevant data source? T

A.2 Is the data used by NIOSH for the case adequate to 

make a determination with regard to POC? T

B. REVIEW OF INTERVIEW AND DOCUMENTATION PROVIDED BY CLAIMANT 

B.1 Did NIOSH properly address all work history 

dates/locations of employment reported by claimant? T

B.2 Did NIOSH properly address all 

incidents/occurrences reported by claimant? T

B.3 Did NIOSH properly address monitoring/ personal 

protection/work practices reported by claimant? T

B.4 Is the interview information consistent with data used 

for dose estimate? T

C. REVIEW OF PHOTON DOSES 

C.1 Was the appropriate procedure used for determining: 

C.1.1 - Recorded Photon Dose? T

C.1.2 - Missed Photon Dose? T T

C.1.3 - Occupational Medical Dose? T T

C.1.4 - Onsite-Ambient Dose? T

C.2 Did the DR properly account for all: 

C.2.1 - Recorded Photon Dose? T

C.2.2 - Missed Photon Dose? T T

C.2.3 - Occupational Medical Dose? T T

C.2.4 - Onsite-Ambient Dose? T

C.3 Is the recorded/assigned dose properly converted to the organ dose of interest for: 

C.3.1 - Recorded Photon Dose? T

C.3.2 - Missed Photon Dose? T

C.3.3 - Occupational Medical Dose? T T

C.3.4 - Onsite-Ambient Dose? T

C.4 Is the organ dose uncertainty properly determined for: 

C.4.1 - Recorded Photon Dose? T

C.4.2 - Missed Photon Dose? T T

C.4.3 - Occupational Medical Dose? T

C.4.4 - Onsite-Ambient Dose? T

D. REVIEW OF SHALLOW (i.e., 7 mg/cm2)/ELECTRON DOSES 

D.1 Was the appropriate procedure used for determining: 

D.1.1 - Recorded Shallow/Electron Dose? T

D.1.2 - Missed Shallow/Electron Dose? T

D.1.3 - Onsite Ambient Dose? T

D.2 Did the DR properly account for all: 

D.2.1 - Recorded Shallow/Electron Dose? T

D.2.2 - Missed Shallow/Electron Dose? T

D.2.3 - Onsite Ambient Dose? T

D.3 Is the recorded/assigned dose properly converted to the organ dose of interest for: 

D.3.1 - Recorded Shallow/Electron Dose? T

 

1 Low means that the deficiency has only a marginal impact on dose. 2 Medium means that the deficiency substantially impacts the dose, but is unlikely to impact the compensability of the case. 3 High means that the deficiency substantially impacts the dose and may also impact the compensability of the case. 

Y-12 National Security Complex Case PIID* 7 S. Cohen & Associates 
CASE PIID* ASSIGNED DOSE: 15.819 rem POC: 10.26% 

Audit Response If No, Potential Significance No. Description of Technical Elements of Review YES N/A NO LOW1 MEDIUM2 HIGH3

D.3.2 - Missed Shallow/Electron Dose? T

D.3.3 - Onsite Ambient Dose? T

D.4 Is the organ dose uncertainty properly determined for: 

D.4.1 - Recorded Shallow/Electron Dose? T

D.4.2 - Missed Shallow/Electron Dose? T

D.4.3 - Onsite Ambient Dose? T

E. REVIEW OF NEUTRON DOSES 

E.1 Was the appropriate procedure used for determining: 

E.1.1 - Recorded Neutron Dose? T

E.1.2 - Assigned Neutron Dose? T

E.1.3 - Missed Neutron Dose? T

E.2 Did the DR properly account for all: 

E.2.1 - Recorded Neutron Dose? T

E.2.2 - Assigned Neutron Dose? T

E.2.3 - Missed Neutron Dose? T

E.3 Is the recorded/assigned dose properly converted to the organ dose of interest for: 

E.3.1 - Recorded Neutron Dose? T

E.3.2 - Assigned Neutron Dose? T

E.3.3 - Missed Neutron Dose? T

E.4 Is the organ dose uncertainty properly determined for: 

E.4.1 - Recorded Neutron Dose? T

E.4.2 - Assigned Neutron Dose? T

E.4.3 - Missed Neutron Dose? T

F. REVIEW OF INTERNAL DOSE: BASED ON HYPOTHETICAL MODEL 

F.1 Is the use of the selected hypothetical internal dose 

model appropriate, based on the likely POC value? T

F.2 Is the use of a hypothetical internal dose model 

appropriate/conservative, based on claimant’s 

available bioassay data,? 

T

F.3 Was the hypothetical dose value correctly derived? T

G. REVIEW OF INTERNAL DOSE: BASED ON BIOASSAY/IMBA 

G.1 Was the appropriate procedure (or section of 

procedure) used for determining likely (>50%), 

unlikely (<50%), or undetermined POC and 

compensability? 

T

G.2 Are bioassay data sufficiently adequate for internal 

dose reconstruction? T

G.3 Are assumptions pertaining to dates of uptake 

reasonable/conservative? T

G.4 Are critical parameters (e.g., solubility class, particle 

size, etc.) used for IMBA organ dose estimates 

appropriate? 

T

G.5 Are assigned uncertainties (measurement errors) for 

bioassay data (used as input to IMBA) appropriate? T

H. Total Number of Deficiencies and Their Combined Potential Significance 6 T

___________________________ 

1

 Low means that the deficiency has only a marginal impact on dose. 2

 Medium means that the deficiency substantially impacts the dose, but is unlikely to impact the compensability of the case. 3

 High means that the deficiency substantially impacts the dose and may also impact the compensability of the case. 

Y-12 National Security Complex Case PIID* 8 S. Cohen & Associates 
2.0 AUDIT OF EXTERNAL DOSES 

2.1 RECORDED PHOTON DOSES 

The claimant was provided with an external dosimeter for the entire PIID* period of interest. 

Since dosimeters were changed quarterly, a total of 80 dosimeters would have been issued to the 

claimant. Of those PIID* calendar quarters, three dosimeters indicated external whole-body 

doses in excess of the lower limit of detection. They were 0.024, 0.090, and 0.070 rem in PIID*, 

PIID*, and PIID*, respectively. 

To maximize these three annual doses, the dose reconstructor multiplied these values by the 

“standard overestimating correction/conversion factor” of 2, as specified in Table 5-2 of 

ORAUT-OTIB-0008. Since the multiplication of recorded dose by 2 yields the 95th percentile 

value, there is no need to assign uncertainty and the dose is entered as a constant. 

For recorded photon dose, entries #1, #2, and #4 are the maximized doses for the years PIID*, 

PIID*, and PIID*, respectively. These values were correctly derived, procedurally compliant, 

and claimant favorable. 

2.2 MISSED PHOTON DOSE 

DOE records indicate that the claimant was monitored on a quarterly bases during the PIID*year 

employment period. For efficiency, NIOSH assumed a total of 80 dosimeter readings for which 

the recorded external deep dose equivalent was zero (or less than LOD). (A review of DOE 

records shows a total of 76 actual number of zero readings.) 

For deriving missed photon doses, the dose reconstructor employed three different procedures 

and provided the following explanation: 

 From Page 5 and 6 of DR Report:

To ensure that the estimated dose has been maximized, a multiplication factor of 2 

has been applied to the reported and missed annual doses. Application of this 

multiplication factor overestimates dose to account for uncertainty in dosimeter 

response and in variability for the dose conversion factor across all organs.8 . . . 

Based on information provided in the Technical Basis Document for the Y-12 

National Security Complex – Occupational External Dosimetry,9 the total number 

of dosimeter cycles assigned was 80 for photons. . . . Based on information 

provided in the Technical Basis Document for the Y-12 National Security 

Complex – Occupational External Dosimetry,9 this results in a maximum 

potential missed dose for [claimant] of 3.280 rem from photons. For the purpose 

of calculating probability of causation, this value was divided by 2 in accordance 

with the External Dose Reconstruction Implementation Guideline.3 

Y-12 National Security Complex Case PIID* 9 S. Cohen & Associates 
The above-cited passages from the DR Report identify the following three separate references/ 

procedures for the calculation of “maximizing” missed photon dose: 

1. Reference #3 is OCAS-IG-001, External Dose Reconstruction Implementation Guideline, 

Rev. 1, 2002. 

2. Reference #8 is ORAUT-OTIB-0008, Technical Information Bulletin: A Standard 

Complex-Wide Conversion/Correction Factor for Overestimating External Doses 

Measured with Thermoluminescent Dosimeter, Rev. 00, 2003. 

3. Reference #9 is ORAUT-TKBS-0014-6, Technical Basis Document for the Y-12 National 

Security Complex – Occupational External Dosimetry, Rev. 00, 2003. 

These three procedures were not intended to be used in combination. By combining these three 

procedures, NIOSH’s dose reconstruction is flawed by a series of errors that fortunately 

cancelled one another, and resulted in a net and final error that involved the inclusion of a GSD 

value of 1.52 for a lognormal distribution, when in fact the annual missed doses for entries #64 

to #83 from Appendix A should have been entered as constants. 

The following summarizes the misinterpretation as well as misuse of the three cited reference: 

• Misinterpretation of ORAUT-OTIB-0008. This procedure identifies a “standard 

overestimating correction/conversion factor” of 2. However, the procedure states that 

this factor “. . . can be applied to all deep doses reported by DOE sites to arrive at a 

claimant-favorable estimate of the dose . . .” [Emphasis added.] 

Thus, the first error was the use of the C/C factor as a multiplier of LOD for missed

doses. For missed dose, ORAUT-OTIB-0008 specifies that the maximized dose is 

simply the product of (LOD)(n), where n is the number of cycles for which the recorded 

dose was zero. 

• Misuse of Procedure. By combining procedures ORAUT-OTIB-0008 with OCAS-IG001, the dose reconstructor cites guidance given in OCAS-IG-001, which recommends 

that for best estimates, missed dose is defined by 2

nLOD ))(( . The use of LOD/2, 

however, is intended for deriving a best estimate of missed dose (as a lognormal value 

with GDS of 1.52. Thus, the first error is cancelled by the second error and yields a 

correct dose, which, however, should have been entered as a constant. The net error then 

is the entry of the dose as a lognormal value with a GSD of 1.52. 

These errors would have been avoided if the dose reconstructor had confined the calculation of 

missed dose to ORAUT-TKBS-0014-6, Table F-6, which defines dosimeter LOD values by time 

periods, as well as provides maximum annual missed dose. 

Y-12 National Security Complex Case PIID* 10 S. Cohen & Associates 
It must be pointed out that nearly identical series of errors for deriving missed photon doses were 

committed by two other dose reconstructors (see Case #PIID* and Case #PIID*) among the 15 

non-AWE cases reviewed in the report. 

While the net impact on assigned doses is insignificant (and, in fact, claimant favorable in all 

three cases), the implication is not. SC&A believes that root cause for these errors must be 

attributed to ambiguous wording/format of procedures, as well as their excess complexity and 

numbers. 

2.3 OCCUPATIONAL MEDICAL EXPOSURES 

NIOSH also assumed that annual chest x-rays were given as a part of a routine medical 

surveillance program of workers. These exposures were acute and the photon energies were 

assumed to range from 30–250 keV. The uncertainty in the x-ray exposures was assumed to be 

normally distributed, with a standard deviation of 30%. Based on these parameters, a dose of 

0.083 rem per x-ray was estimated, or a total of 1.660 rem over the PIID*-year period of 

interest. 

The 1.660 rem dose to the testes from 20 medical x-rays is based on the assumption that the 

claimant received a single conventional anterior-posterior x-ray annually. The estimate of dose 

to the prostate may have been intended to be claimant favorable, in that NIOSH used the dose to 

the organ with the maximum dose per x-ray (e.g., the breast, lateral chest view) rather than the 

dose to the testes (the typical surrogate for the prostate) from the values published in Table 4.0-1 

of ORAUT-OTIB-0006 for PIID*– PIID* exposures. The dose was then increased by 30% to 

account for uncertainty. 

Had the actual value for the testes been used, the estimated dose to the prostate would have been 

more than three orders of magnitude lower. While the dose estimate provided in the dose 

reconstruction report is clearly claimant favorable, it is unwarranted and clearly not scientifically 

valid. Using a parameter value representing dose to the breast rather than the value for dose to 

the testes when reconstructing a dose to the prostate from chest x-rays detracts from the scientific 

quality of the dose reconstruction and violates the intent of claimant favorability, as defined in 

42 CFR 82. 

Y-12 National Security Complex Case PIID* 11 S. Cohen & Associates 
3.0 AUDIT OF INTERNAL DOSES 

Records obtained from DOE include periodic urinalysis data from the worker. Samples collected 

from PIID*– PIID* contained between 0–20 dpm uranium. Most samples collected after PIID*

were found with uranium concentrations less than the detection threshold and were less than 1 

dpm per day in all but one sample. Between 1–5 mg uranium were reported, based on lung 

counts conducted during the PIID*. In vivo lung counts conducted in PIID* and PIID* failed 

to find any uranium or actinium. As a result of these relatively low potential intakes, the NIOSH 

internal dose reconstruction was based on the hypothetical intake described in ORAUT-OTIB0002. The dose reconstruction report makes reference to the 28 radionuclides included in the 

hypothetical intake, indicating that the “Site with a reactor” combined with the “uranium site” 

scenarios were utilized. The list includes all nuclides identified on the CATI report as “present” 

and most of the nuclides identified, as “unknown” during claimant’s employment. 

In the interview, the worker indicated participating in breath and fecal monitoring while 

employed at the Y-12 complex in addition to urine and in vivo monitoring. The only data 

forwarded for review as part of this audit were urinalysis and in vivo data. NIOSH did not 

comment on breath or fecal monitoring data in the dose reconstruction report. 

The internal dose to the prostate, determined by NIOSH based on the methodology described in 

ORAUT-OTIB-0002, was 12.151 rem. The NIOSH report does not describe or present the 

relevant parameter values utilized to determine this dose; it was presumably generated with the 

Excel® workbooks spreadsheets titled “Maximum Internal Dose Calculation Workbook.xls” and 

“Maximum Internal Dose Calculation non-Uranium Facility Workbook.xls” developed in 

support of ORAUT-OTIB-0002. 

At the time of the dose reconstruction, the Excel® workbook spreadsheets did not allow for a 

direct calculation of the prostate dose, and the use of the colon as the highest non-metabolic 

surrogate organ was, therefore, correct. Nevertheless, it is worth noting that since the time of 

this dose reconstruction, these spreadsheets have been updated and now include the prostate. For 

this claim, a direct prostate dose of 10.05 rem was derived, which is about 2.5 rem lower than the 

more claimant-favorable dose of 12.5 rem assigned by NIOSH. 

Y-12 National Security Complex Case PIID* 12 S. Cohen & Associates 
4.0 CATI REPORT AND RADIOLOGICAL INCIDENTS 

No radiological incidents were identified in either DOE records or in the CATI report and no 

inconsistencies were noted that adversely affect the dose reconstruction report. 

Y-12 National Security Complex Case PIID* 13 S. Cohen & Associates 
5.0 SUMMARY CONCLUSIONS 

Issues of concern in the dose reconstruction for Case PIID* were confined to dose estimates in 

behalf of missed photon doses and occupational medical exposures. 

For missed photon doses, multiple errors reflect the inappropriate combined use of three separate 

procedures. Nearly identical errors were committed in behalf of two other cases (i.e., Case #

PIID* and Case # PIID*), which suggest that the root cause may be the ambiguous guidance 

provided in these procedures. 

For assigned occupational medical exposure, excessively high doses were assigned that reflect 

the inappropriate substitution of surrogate organs. 

Y-12 National Security Complex Case PIID* 14 S. Cohen & Associates 
REFERENCES 

Kathren, R.L., Shockley, V.E., Thomas, E.M., Taulbee, T.D. 2003. “Technical Information 

Bulletin: Dose Reconstruction from Occupationally Related Diagnostic X-ray Procedures,” 

ORAUT-OTIB-0006. 

NIOSH. 2002. “NIOSH-Interactive Radioepidemiological Program (NIOSH-IREP) Technical 

Documentation,” Final Report. June 18, 2002. 

OCAS-IG-001, 2002. “External Dose Reconstruction Implementation Guideline,” Revision 1. 

August 2002. 

ORAUT-TKBS-0014-6. 2003. “Technical Basis Document for the Y-12 National Security 

Complex – Occupational External Dosimetry,” November 19, 2003. 

ORAUT-OTIB-0002. 2004. “Technical Information Bulletin: Maximum Internal Dose 

Estimates for Certain DOE Complex Claims,” Rev. 00 PC-2. January 10, 2004. 

ORAUT-OTIB-0008. 2003. “Technical Information Bulletin for a Standard Complex-Wide 

Conversion/Correction Factor for Overestimating External Doses Measured with 

Thermoluminescent Dosimeter,” Rev. 00. November 7, 2003. 

Y-12 National Security Complex Case PIID* 15 S. Cohen & Associates 
APPENDIX A: IREP INPUT

Table below has been deleted, please see hard copies labeled ‘#20 – Y12 

National Security Complex’ 

Y-12 National Security Complex Case PIID* 16 S. Cohen & Associates 
APPENDIX A (Continued) 

Table below has been deleted, please see hard copies labeled ‘#20 – Y12 

National Security Complex’ 

Y-12 National Security Complex Case PIID* 17 S. Cohen & Associates