DRAFT 

ADVISORY BOARD ON RADIATION AND WORKER HEALTH 

NATIONAL INSTITUTE FOR 

OCCUPATIONAL SAFETY AND HEALTH 

A REVIEW OF NIOSH’S PROGRAM EVALUATION REPORT 

OCAS-PER-011: K-25 TBD AND TIB REVISIONS 

Contract No. 200-2009-28555 

SCA-TR-PR2013-0080, Rev. 0 

Prepared by 

Rose Gogliotti 

SC&A, Inc. 

S. Cohen & Associates 

1608 Spring Hill Road, Suite 400 

Vienna, VA 22182 

April 2013 

Disclaimer 

This document is made available in accordance with the unanimous desire of the Advisory Board on 

Radiation and Worker Health (ABRWH) to maintain all possible openness in its deliberations. However, 

the ABRWH and its contractor, SC&A, caution the reader that at the time of its release, this report is predecisional and has not been reviewed by the Board for factual accuracy or applicability within the 

requirements of 42 CFR 82. This implies that once reviewed by the ABRWH, the Board’s position may 

differ from the report’s conclusions. Thus, the reader should be cautioned that this report is for 

information only and that premature interpretations regarding its conclusions are unwarranted.

 
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Document No. 

SCA-TR-PR2013-0080 

S. COHEN & ASSOCIATES: 

Technical Support for the Advisory Board on

Radiation & Worker Health Review of 

NIOSH Dose Reconstruction Program 

Effective Date: 

Draft – April 24, 2013 

A Review of NIOSH’s Program Evaluation 

Report OCAS-PER-011: K-25 TBD and TIB 

Revisions

 Page 2 of 34 

Task Manager/Reviewer: 

________________________ Date: ___________ 

U. Hans Behling, PhD, MPH 

Supersedes: 

N/A 

Project Manager: 

________________________ Date: ___________ 

John Stiver, CHP 

Reviewer(s): 

 Kathleen Behling 

 John Stiver 

Record of Revisions 

Revision 

Number 

Effective 

Date Description of Revision 

0 (Draft) 04/24/2013 Initial issue 
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TABLE OF CONTENTS 

 

Abbreviations and Acronyms ..........................................................................................................5 

1.0 Statement of Purpose ...........................................................................................................6 

2.0 Subtask 1: Identify the Circumstances that Necessitated OCAS-PER-011........................8 

2.1

....................................................................................................................8 

SC&A’s Comments on Non-Construction Trades Worker Guidance 

Changes

2.2 SC&A’s Comments on Construction Trades Worker Guidance Changes.............12 

3.0 Subtask 2: Assess NIOSH’s Approach and Methods for Corrective Action....................13 

3.1 SC&A’s Comments on Corrective Approach........................................................13 

4.0

.......15 

Subtask 3: Evaluate the Program Evaluation Report’s Stated Approach for 

Identifying the Number of Dose Reconstructions Requiring Re-evaluation of Dose

4.1 SC&A’s Comments on Selection Criteria .............................................................15 

4.1.1 SC&A’s Comments on Non-CTW Coworker Selection Criteria ..............15 

4.1.2 SC&A’s Comments on CTW Selection Criteria .......................................16 

4.2 SC&A Comments on Execution of Selection Criteria...........................................17 

5.0

.............................................................................................20 

Subtask 4: Conduct Audits of a Sample-Set of Dose Reconstructions 

Affected by OCAS-PER-011

6.0 Summary Conclusions.......................................................................................................21 

References......................................................................................................................................22 

Appendix A: Comparison of ORAUT-TKBS-0009-6 Rev. 00 Coworker Model to Current 

Guidance ............................................................................................................................23 

Appendix B: Comparison of ORAUT-OTIB-0026 Rev. 00 Coworker Model to Current 

Model.................................................................................................................................26 

Appendix C: Comparison of ORAUT-OTIB-0026 Rev. 00 PC-1 Coworker Model to 

Current Model....................................................................................................................29 

Appendix D: Percent Change Comparison Between Historical Coworker Models and New 

CTW Coworker Model ......................................................................................................32 
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LIST OF TABLES 

Table 2-1.

..................................................................10 

Summary of Yearly Percent Change Comparison to Current Non-CTW 

Coworker Guidance for Penetrating Dose

Table 2-2.

..........................................................................................12 

Summary of Percent Change Comparison of Historical Coworker Guidance to 

CTW Coworker Guidance

Table 4-1. Summary of Impacted Claims....................................................................................17 

LIST OF FIGURES 

Figure 2-1. 95 Percentile Penetrating Coworker Dose Comparison .............................................9 th

Figure 2-2. 50 Percentile Penetrating Coworker Dose Comparison .............................................9 th

Figure 2-3. 95 Percentile Shallow Coworker Dose Comparison ................................................10 th

Figure 2-4. 50 Percentile Shallow Coworker Dose Comparison ................................................11 th
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ABBREVIATIONS AND ACRONYMS 

CF Correction Factor 

CTW Construction Trades Worker 

DOL (U.S.) Department of Labor 

DR Dose Reconstruction 

EE Energy Employee 

ICE Individual Case Evaluation 

NIOSH National Institute for Occupational Safety and Health 

NOCTS NIOSH OCAS Claims Tracking System 

OCAS Office of Compensation Analysis and Support 

ORAUT Oak Ridge Associated Universities Team 

PEP Program Evaluation Plan 

PER Program Evaluation Report 

POC Probability of Causation 

SC&A S. Cohen and Associates 

TBD Technical Basis Document 

TIB Technical Information Bulletin 
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1.0 STATEMENT OF PURPOSE 

 

To support dose reconstruction (DR), the National Institute for Occupational Safety and Health 

(NIOSH) and the Oak Ridge Associated Universities Team (ORAUT) assembled a large body of 

guidance documents, workbooks, computer codes, and tools. In recognition of the fact that all of 

these supporting elements in DR may be subject to revisions, provisions exist for evaluating the 

effect of such programmatic revisions on the outcome of previously completed DRs. Such 

revisions may be prompted by document revisions due to new information, misinterpretation of 

guidance, changes in policy, and/or programmatic improvements. 

The process for evaluating potential impacts of programmatic changes on previously completed 

DRs has been proceduralized in Revision 2 of OCAS-PR-008, Preparation of Program 

Evaluation Reports and Program Evaluation Plans, dated December 6, 2006. This procedure 

describes the format and methodology to be employed in preparing a Program Evaluation Report 

(PER) and a Program Evaluation Plan (PEP). 

A PER provides a critical evaluation of the effect(s) that a given issue/programmatic change may 

have on previously completed DRs. This includes a qualitative and quantitative assessment of 

potential impacts. Most important in this assessment are the potential impacts on the Probability 

of Causation (POC) of previously completed DRs with POCs <50%. 

A PEP may be issued as a formal notification of an impending PER. The PEP provides a 

preliminary description of the issue(s) that will be addressed in the PER, and summarizes the 

likely scope of the effort required to complete the PER. 

During an Advisory Board Subcommittee on Procedures Review meeting on July 21, 2012, 

SC&A was tasked by the Advisory Board to conduct a review of OCAS-PER-011, K-25 TBD 

and TIB Revisions. In conducting a PER review, SC&A is committed to perform the following 

five subtasks, each of which is discussed in this report: 

Subtask 1: Assess NIOSH’s evaluation/characterization of the “issue” and its potential impacts 

on DR. Our assessment intends to ensure that the issue was fully understood and 

characterized in the PER. 

Subtask 2: Assess NIOSH’s specific methods for corrective action. In instances where the PER 

involves a technical issue that is supported by document(s) [e.g., white papers, technical 

information bulletins (TIBs), procedures] that have not yet been subjected to a formal 

SC&A review, Subtask 2 will include a review of the scientific basis and/or sources of 

information to ensure the credibility of the corrective action and its consistency with 

current/consensus science. Conversely, if such technical documentation has been 

formalized and previously subjected to a review by SC&A, Subtask 2 will simply provide 

a brief summary/conclusion of this review process. 

Subtask 3: Evaluate the PER’s stated approach for identifying the universe of potentially 

affected DRs, and assess the criteria by which a subset of potentially affected DRs was 

selected for re-evaluation. The second step may have important implications in instances 
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where the universe of DRs is too large and, for reasons of practicality, NIOSH’s reevaluation is confined to a subset of DRs. In behalf of Subtask 3, SC&A will also 

evaluate the timeliness for the completion of the PER. 

Subtask 4: Conduct audits of DRs affected by the PER under review. The number of DRs 

selected for audit for a given PER will vary. The selection of the DRs and the total 

number of DR audits per PER will be made by the Advisory Board. 

Subtask 5: Prepare a comprehensive written report that contains the results of the above-stated 

subtasks, along with our review conclusions.
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2.0 SUBTASK 1: IDENTIFY THE CIRCUMSTANCES THAT 

NECESSITATED OCAS-PER-011 

OCAS-PER-011 was issued on November 26, 2007, in response to a series of technical revisions 

to the Technical Basis Document (TBD) for the K-25 Site – Occupational External Dose

(ORAUT-TKBS-0009-6) and two ORAUT TIBs that affected this TBD. While some changes 

incorporated in these revisions increased the assigned doses, others resulted in a decrease. A 

chronological summary of document modifications that impacted external dose estimates is 

provided below: 

 November 24, 2004, the external dose section (ORAUT-TKBS-0009-6) of the Oak Ridge 

Gaseous Diffusion Plant (K-25) was issued. This TBD documented an external dose 

coworker model for unmonitored workers at K-25. Prior to the issuance of ORAUTTKBS-0009-6 Rev. 0, there was no external coworker model for K-25. 

 May 31, 2005, ORAUT-OTIB-0026, External Coworker Dosimetry Data for the K-25 

Site, was issued. This TIB replaced the coworker guidance contained in ORAUT-TKBS0009-6. The revised coworker model changed the external coworker values to account 

for missed dose. This resulted in an increased coworker dose during some years. 

 July, 29, 2005, ORAUT-OTIB-0026 Rev. 00 PC-1 was issued. The revision reduced 

most of the missed doses included in the previous revision. 

 November 15, 2006, ORAUT-OTIB-0026 Rev. 00 PC-2 was issued. This revision 

incorporated guidance contained in ORAUT-OTIB-0052, Parameters to Consider When 

Processing Claims from Construction Trade Workers (Rev. 00 issued August 31, 2006) 

and added Section 8.0 and Table 3 for processing claims of construction trades workers 

(CTWs). 

Other K-25 guidance documents have been revised; however, these revisions do not have an 

impact on the DR methodology. 

2.1 SC&A’S COMMENTS ON NON-CONSTRUCTION TRADES WORKER 

GUIDANCE CHANGES 

SC&A found the PER-011 description of the circumstances surrounding the issuance of the PER, 

which was contained in a single paragraph, to be exceedingly vague. To ascertain the full impact 

of the revised guidance, SC&A compared the historical K-25 coworker models against the most 

current non-CTW coworker guidance (ORAUT-OTIB-0026 Rev. 00 PC-2). Figures 2-1 and 2-2 

illustrate a direct yearly comparison of the four penetrating dose models. 

A direct comparison shows that, in general, the ORAUT-OTIB-0026 Rev. 00 and Rev. 00 PC-1 

95th and 50th percentile coworker models for penetrating dose match or overestimate coworker 

dose in the Rev. 00 PC-2 model. In contrast, the coworker guidance in ORAUT-TKBS-0009-6 

Rev. 00 consistently underestimated (pre-1975) dose compared to coworker guidance in 

ORAUT-OTIB-0026 Rev. 00 PC-2. 
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Figure 2-1. 95th Percentile Penetrating Coworker Dose Comparison 

Figure 2-2. 50th Percentile Penetrating Coworker Dose Comparison 
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Because the assignment of coworker dose is dependent on the length of employment, time of 

employment, cancer location, and job description, SC&A also analyzed the annual percent 

change between historical and current coworker guidance documents. The yearly 95th and 50th

percentile coworker model values for each revision and a percent change comparison to the 

current K-25 coworker guidance document, ORAUT-OTIB-0026 Rev. 00 PC-2, is included as 

Appendices A through C of this report. For the convenience of the reader, a summary of these 

comparisons is provided in Table 2-1. Red and green texts are used for added emphasis to 

negative and positive percent changes, respectively. 

Table 2-1. Summary of Yearly Percent Change Comparison to Current Non-CTW 

Coworker Guidance for Penetrating Dose 

ORAUT-TKBS-0009-6 

Rev. 00 

ORAUT-OTIB-0026 

Rev. 00 

ORAUT-OTIB-0026 

Rev. 00 PC-1 

Percentile 95th 50th 95th 50th 95th 50th 

Average 84.3% 613.0% -17.6% -5.6% 0.0% 0.0% 

Minimum -93.8% -81.6% -93.9% -43.9% 0.0% 0.0% 

Maximum 716.5% 2900.0% -1.0% 0.0% 0.0% 0.0% 

Coworker guidance documents also contain non-penetrating coworker dose models. Figures 2-3 

and 2-4 illustrate a direct yearly comparison of non-penetrating dose for the 95th and 50th

percentile coworker models, respectively. 

Figure 2-3. 95th Percentile Shallow Coworker Dose Comparison 
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Figure 2-4. 50th Percentile Shallow Coworker Dose Comparison 

Unlike the penetrating models, all historical shallow dose models overestimated shallow 

coworker dose when compared to the current coworker guidance contained in ORAUT-OTIB0026 Rev. 00 PC-2. SC&A notes that use of the non-penetrating 50th percentile ORAUT-OTIB0026 Rev. 00 coworker model during some years (1968, 1975–1976, and 1979) resulted in an 

underestimated dose when compared to the current coworker model. This has a potential impact 

only on cancers located on the skin, lip, breast and/or testicle for coworker dose assigned during 

1968, 1975–1976, and 1979. Considering the fact that the corresponding 50th percentile 

penetrating dose model is an overestimate of dose compared to the current model, only a small 

impact on overall coworker dose would be expected. While NIOSH did not acknowledge this 

possibility in PER-011, SC&A does not anticipate that this would result in significant changes in 

any cases. No K-25 cases will require re-evaluation based solely on the shallow dose assigned. 

The guidance document dose comparisons show that, in general, non-CTW penetrating coworker 

dose was overestimated by historical coworker models. The exception to this generality is the 

ORAUT-TKBS-0009-6 Rev. 00 non-CTW penetrating coworker dose models. It is evident from 

Table 2-1 that, on average, the yearly coworker models underestimated dose by 84.3% for the 

95th percentile model and 613% for the 50th percentile model. Coworker dose calculated using 

either percentile from the ORAUT-TKBS-0009-6 Rev. 00 model would be underestimated 

compared to the current coworker model. Cases done using this guidance will require reevaluation and possible rework. 
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2.2 SC&A’S COMMENTS ON CONSTRUCTION TRADES WORKER GUIDANCE 

CHANGES

Construction Trades Worker (CTW) coworker model guidance was not available until the 

issuance of ORAUT-OTIB-0052. As a result, many Energy Employees (EEs) with positions that 

are classified as construction trades may have received an underestimated coworker dose in 

comparison to DRs completed under current guidance. Using the updated ORAUT-OTIB-0026 

(Rev. 00 PC-2), CTWs receive a measured coworker dose of 1.4 times greater than non-CTWs. 

Missed coworker dose is unaffected by this change. Note that the CTW coworker guidance 

contained in ORAUT-OTIB-0052 was reviewed by SC&A in Draft Review of ORAUT-OTIB0052, Revison 1: Parameters to Consider when Processing Claims for Construction Trade 

Workers (SCA-TR-PR2011-0004, July 2011). 

To quantify the possible impact on cases completed before CTW coworker model guidance was 

available, SC&A compared historical coworker models with the ORAUT-OTIB-0026, Rev. 00 

PC-2 CTW model. The results of these comparisons are documented in Appendix D. For the 

convenience of the reader, a summary of these comparisons is provided in Table 2-2. Red and 

green texts are used for added emphasis to negative and positive percent changes, respectively. 

Table 2-2. Summary of Percent Change Comparison of Historical Coworker Guidance 

to CTW Coworker Guidance 

95th Percentile 50th Percentile 

ORAUTTKBS-0009-6 

Rev. 00 

ORAUTOTIB-0026 

Rev. 00 

ORAUTOTIB-0026 

Rev. 00 PC-1 

ORAUT-TKBS0009-6 Rev. 00 

ORAUTOTIB-0026 

Rev. 00 

ORAUTOTIB-0026 

Rev. 00 PC-1 

Average 98.3% -8.7% 10.7% 616.5% -4.6% 1.1% 

Min -92.1% -93.9% 0.0% -81.6% -43.9% 0.0% 

Max 745.6% 17.8% 28.2% 2900.0% 13.9% 15.3% 

SC&A’s comparison shows that historical coworker models underestimated CTW coworker dose 

during most years prior to 1975. Thus, each CTW case where coworker dose was assigned using 

a historical model was likely underestimated. 

SC&A finds it noteworthy that the ORAUT-TKBS-0009-6 and OCAS-OTIB-0026 Rev. 00 

coworker models after 1975 significantly overestimated dose to CTWs in comparison to 

ORAUT-OTIB-0026 (Rev. 00 PC-2). If assigned coworker dose to CTWs began in 1975 or after 

and used these documents, the case would not require revision. 
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3.0 SUBTASK 2: ASSESS NIOSH’S APPROACH AND 

METHODS FOR CORRECTIVE ACTION 

NIOSH used the following set of criteria to determine the universe (or maximum potential 

number) of claims that could have been impacted by the K-25 coworker model document 

revisions: 

(1) Claim included employment at K-25 

(2) Claims were completed between the date of the initial coworker model (November 24, 

2004) and the date of the issuance of ORAUT-OTIB-0052 (August 31, 2006) 

(3) Claim resulted in a POC of less than 50% 

Using these criteria (as of September 2007), NIOSH identified a total of 432 cases from K-25 

that were potentially impacted by revised coworker model guidance. 

3.1 SC&A’S COMMENTS ON CORRECTIVE APPROACH 

Critical to the successful implementation of OCAS-PER-011 is the accurate and complete 

identification of all potentially affected claims. In general, SC&A agrees with the methodology 

used by NIOSH to identify the 432 potentially affected claims. However, SC&A questions the 

dates selected to bound the potentially impacted claims. The start date (November 24, 2004) is 

the date ORAUT-TKBS-0009-6 Rev. 00 was issued. SC&A’s concern involves those claims 

where the EE was unmonitored or inadequately monitored and their DR was adjudicated before 

the K-25 external coworker model was issued. 

At the writing of this review, SC&A is unaware of any past effort by NIOSH that would have 

identified and assigned coworker doses to those claims that had been adjudicated before their 

site-specific coworker model had been issued in order to make them eligible for evaluation under 

OCAS-PER-011, or of a future effort to do so. If SC&A is correct in both assumptions, some 

cases may (1) have an incomplete DR and (2) be excluded from a revised DR, as provided by 

screening criteria cited in Section 3.0 above. 

Finding #1 (Conditional): OCAS-PER-011 May Be Restrictive in Identifying All CTWs 

and Unmonitored Workers

At this time, there is uncertainty about the fate of claims where the EE was unmonitored or 

inadequately monitored and their DR had been adjudicated before the issuance of the K-25 

coworker model. During our review, SC&A randomly identified several DRs completed prior to 

the issuance of the K-25 TBD, which included unmonitored/ambient external dose. However, 

these claims were not captured in the “universe” of potentially impacted claims under PER-011. 

This is considered a conditional finding, because there is uncertainty regarding the methods used 

to reconstruct the unmonitored dose for these cases. It should be noted that a similar finding was 

identified in SC&A’s review of OCAS-PER-014, A Review of NIOSH’s Program Evaluation 

Report OCAS-PER-014, “Construction Trade Workers,” SCA-TR-PR2012-0014. However, this 

finding was closed based on NIOSH’s statement that cases requiring unmonitored dose were 
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held pending a coworker model. SC&A wants to verify that NIOSH’s response to that finding is 

accurate in these K-25 cases. 

SC&A also questions the end date of August 31, 2006, being selected as the end of potentially 

affected claims. Although this is the date OTIB-0052 was issued, ORAUT-OTIB-0026 Rev. 00 

PC-2, which incorporated provisions of OTIB-0052, was not issued until November 15, 2006. 

Missed and measured coworker dose is presented as a single value in the previous revision 

(ORAUT-OTIB-0026 Rev. 00 PC-1). In order for a DR to be properly implemented for a CTW, 

measured coworker dose must be adjusted separate from missed coworker dose. Using the 

guidance from OTIB-0052 and ORAUT-OTIB-0026 Rev. 00 PC-1, a DR would not be able to 

calculate CTW dose correctly unless the dose reconstructor was able to determine the measured 

versus missed portion of the external dose. SC&A believes it is unlikely that CTW coworker 

dose was assessed correctly prior to November 15, 2006. 

As of March 26, 2013, SC&A identified 57 K-25 claims with DR “sent dates” between August 

31, 2006, and November 15, 2006, and with POCs less than 50%. To determine if any cases 

within this window might have been missed by the PER-011 criteria end date, SC&A selected 

five cases at random with job titles matching those of CTWs. Three of the five cases had 

coworker dose assigned. All three cases had CTW coworker dose calculated incorrectly; a 

1.4 correction factor (CF) was applied to both missed and measured CTW coworker dose. It 

should be noted that although calculated incorrectly, the means by which CTW dose was 

calculated resulted in a dose greater than otherwise would have been calculated. Since this 

resulted in an overestimate of dose, claims done in this time period would not require revision 

and can reasonably be excluded from the “universe” of claims potentially requiring revision. 

Other than the start date concern addressed in Finding #1, SC&A agrees with the methodology 

used by NIOSH to identify the “universe” of claims potentially impacted by the revised 

coworker models at K-25. 
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4.0 SUBTASK 3: EVALUATE THE PROGRAM EVALUATION 

REPORT’S STATED APPROACH FOR IDENTIFYING THE NUMBER OF 

DOSE RECONSTRUCTIONS REQUIRING RE-EVALUATION OF DOSE 

NIOSH used the screening criteria listed in Section 3.0 to identify a universe of 432 potentially 

impacted claims. NIOSH will remove all cases that have been returned due to another PER and 

those that were returned for other reasons prior to evaluations. These claims are to be revised 

using the most current technical guidance, which includes coworker guidance; therefore, they do 

not require rework. 

Each of the remaining claims should be reviewed by NIOSH to determine if external coworker 

data were used in the DR. NIOSH will request return for the following two reasons: 

(1) Claims completed before May 21, 2005, and completed using an external coworker 

model. 

(2) Claims completed between May 21, 2005, and August 31, 2006, using external coworker 

data and are deemed CTWs 

Documentation will be provided to the Department of Labor (DOL) for cases that do not meet 

these criteria and therefore did not require rework. 

4.1 SC&A’S COMMENTS ON SELECTION CRITERIA 

SC&A identified that the selection criteria must capture two distinct sets of claims: non-CTW 

claims and CTW claims. Selection criteria for both types of claims are discussed separately 

below. 

4.1.1 SC&A’s Comments on Non-CTW Coworker Selection Criteria 

The initial criterion includes all cases done with a coworker model prior to May 21, 2005. 

SC&A finds it interesting that NIOSH selected May 21, 2005, as the criterion end date, because 

ORAUT-OTIB-0026 Rev. 00 was not issued until May 31, 2005. In addition, since each DR 

report identifies numerous dates (i.e., “Calculation Performed,” “Peer Review Completed,” and 

“DR Approved”), SC&A is unsure which specific date NIOSH uses as the “completion date.” 

SC&A believes the date the calculations were completed should be the completion date used by 

NIOSH. However, the NIOSH OCAS Claims Tracking System (NOCTS) database does not 

accommodate searches based on calculation completion date; therefore, SC&A cannot verify that 

all potentially impacted cases were captured. 

Finding #2: Date Inconsistencies May Have Missed Non-CTW Coworkers

The end date of the first selection criteria, May 21, 2005, is 10 days before the issuance of 

ORAUT-OTIB-0026 Rev. 00. This may be an administrative oversight; however, it means any 

non-CTW cases completed in this 10-day window would not be captured by the selection 

criteria, and therefore not eligible for re-evaluation. NIOSH should investigate further to ensure 
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no cases were inadvertently missed by this inconsistency. In addition, SC&A would like 

clarification regarding which date NIOSH considers the DR “completion date.” 

Based on SC&A’s comparison of historical to current coworker guidance contained in 

Appendices A–C, any case (prior to 1975) that used the penetrating dose coworker model 

contained in ORAUT-TKBS-0009-6 underestimated potential coworker dose. Since the first 

criterion requires all cases completed using ORAUT-TKBS-0009-6 and having a coworker 

model should be sent to NIOSH for rework, SC&A has no concerns that any claims (other than 

those discussed in Finding #2) were missed if the first selection criterion was properly executed. 

The second criterion specifically excludes non-CTWs and applies to cases done using the 

guidance of ORAUT-OTIB-0026 revisions. SC&A’s analysis of the early revisions of ORAUTOTIB-0026 (discussed in Section 2.1 and Appendices A through C) shows that non-CTW cases 

completed using this guidance received a larger coworker dose than if they were completed with 

the current models from ORAUT-OTIB-0026 Rev. 00 PC-2. Since dose was overestimated by 

early ORAUT-OTIB-0026 models, case rework would not result in a higher POC. As such, 

these cases do not require revision. 

Other than the first selection criterion’s end date discussed in Finding #2, SC&A finds the 

selection criteria to be inclusive of cases potentially impacted by the updates to coworker 

guidance. 

4.1.2 SC&A’s Comments on CTW Selection Criteria 

The first criterion captures all claims that include coworker dose and were completed prior to 

May 21, 2005. Since no career distinction is needed to trigger revision under this criterion, all 

CTW claims that use coworker dose and guidance from ORAUT-TKBS-0009-6 Rev. 00 will be 

captured. SC&A’s comparison discussed in Section 2.2 and documented in Appendix D shows 

that all CTW coworker doses (pre-1975) were underestimated by the ORAUT-TKBS-0009-6 

Rev. 00 coworker model that predated CTW coworker guidance. 

The second criterion requires that all CTW coworker claims completed between the issuance of 

ORAUT-OTIB-0026 Rev. 00 and OTIB-0052 be returned to NIOSH for re-evaluation. As 

shown in Appendix D, most newly identified CTW coworker claims are expected to have an 

increase in dose. Rework is required to determine the extent of this increase. 

Finding #3: CTW Identification Method Not Specified

SC&A questions what technique NIOSH used to identify CTW claims. SC&A speculates that a 

keyword search method similar to the one used in OCAS-PER-014 to identify CTW claims was 

used; however, no information indicating how CTW cases were identified is given in PER-011. 

Since proper identification of CTW claims is a crucial element in ensuring that all impacted 

claims are evaluated and the term CTW is somewhat subjective, the technique used should be 

documented. 
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4.2 SC&A COMMENTS ON EXECUTION OF SELECTION CRITERIA 

The extent to which NIOSH has screened and evaluated the universe of the 432 claims by means 

of the above-cited criteria was not discussed in OCAS-PER-011. As such, NIOSH did not 

identify the actual number of CTW claims (from among the 432 claims) eligible for a new DR. 

Because PER-011 was incomplete in this respect, SC&A requested that NIOSH provide a list of 

the 432 claims potentially impacted and the evaluation status of each claim. This list is 

summarized below. 

Table 4-1. Summary of Impacted Claims 

Number of 

Claims Impacted Status Meaning of Designation 

94 Return to NIOSH NIOSH requested the case be returned for a new DR 

266 No Return necessary NIOSH requested that the case NOT be returned for a 

new DR 

41 Returned Prior to Evaluation Case was returned to NIOSH prior to completing the 

PER Evaluation 

31 Return Requested for another PER NIOSH requested the case be returned based on a 

different PER 

NIOSH identified 94 claims that met one of the two selection criteria and were returned, yet 

indicated to SC&A that only 69 of these claims were reworked. The remaining 25 claims were 

not revised. It appears that all returned cases have letters in their files stating the following: 

 It is not possible to determine the extent to which this claim is affected without 

reworking the case. NIOSH is therefore requesting the claim be returned for a 

new dose reconstruction. After the claim is returned, NIOSH will prepare a new 

dose reconstruction that applies all current methods. Because of this, no 

additional evaluations are necessary. 

SC&A did not find any documentation in the 25 claims indicating why the claim was not 

revised. If NIOSH has no intention of revising these claims, it should be noted in the 

EE’s files. Without this documentation, it appears that these cases are still awaiting 

revision, even though they have been returned to DOL. 

Finding #4: Not All Cases Returned to NIOSH were Reworked, which May Result in 

Claims Not Being Considered under Other PERs

During the course of this review, SC&A noted that 25 cases were returned to NIOSH as a result 

of PER-011, but a revised DR was not performed for any of them. In reviewing the files for 

several of these 25 claims, it was determined that the cases were also potentially impacted by 

other recently issued PERs. For example, one case file contained an Individual Case Evaluation 

(ICE) memo for PER-011 stating, “The dose reconstruction for NIOSH ID [redacted] was reevaluated in accordance with the above referenced Program Evaluation Report (PER) [OCASPER-011]”, which is inaccurate. The case file also contains an ICE memo for OCAS-PER-014 

indicating, “No evaluation was performed . . . because this claim has been returned or a return 

has been requested.” Since this claim was not reworked under PER-011 (and revised using the 
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most current technical guidance), it was also not considered under PER-014. This is potentially 

indicative of a larger issue that encompasses all PER evaluations. To SC&A’s knowledge, there 

is no designation for cases that were returned to NIOSH yet not revised that would allow them to 

re-enter the pool of cases eligible for re-evaluation. Because of this, there is a possibility that all 

cases that are returned and not revised have been missed inadvertently by other PER evaluations. 

NIOSH needs to investigate this issue further. 

Based on the broad selection criteria in PER-011, SC&A was surprised by how few cases were 

returned to NIOSH. For this reason, SC&A performed an independent screening of the 432 

claims based on their job title, as listed in the NOCTS database, and the CTW screening criteria1

specified in OCAS-PER-014, Appendix A. (It should be noted that OCAS-PER-014 has 

previously been reviewed by SC&A and was determined to adequately capture most CTW 

claims.) Using this technique, SC&A identified 162 (38%) of the 432 claims that reasonably 

could be deemed CTW cases. In this subset, 73 CTW claims were deemed “no return necessary” 

and 46 were returned to NIOSH.2 Assuming the selection criteria were implemented correctly, 

this would mean that ~40% of CTW claims were for unmonitored EEs. 

Based on SC&A’s experience with DR reviews impacted by ORAUT-OTIB-0052, SC&A found 

this to be a particularly low number of cases. Therefore, SC&A selected 7 CTW claims at 

random (~10%) from those CTW cases that NIOSH deemed “no return necessary” to determine 

if they were monitored and coworker dose assigned. SC&A found the following: 

 2 cases – CTW was monitored and no coworker dose assigned 

 1 case – CTW was unmonitored and no coworker dose assigned 

 2 cases – CTW was unmonitored and assigned coworker dose for K-25 

 2 cases – CTW was simultaneously employed at other Oak Ridge facilities and assigned 

coworker dose from another facility 

Based on the selection criteria identified in Section 3.0 of PER-011, four of the seven randomly 

selected cases should have been returned to NIOSH. These cases may or may not require 

rework; however, they should have been identified as potentially needing rework according to 

the selection criteria and sent back to NIOSH. This indicates NIOSH either used more definitive 

screening criteria than cited in PER-011 or the criteria were improperly applied. 

Finding #5: Improper Application of Selection Criteria

Based on SC&A’s initial screening of CTW claims deemed “no return necessary,” it appears that 

selection criteria were not properly applied as stipulated in PER-011. Four of the seven claims 

screened should have been identified by the selection criteria listed in Section 3.0 of OCASPER-011 and returned to NIOSH for rework. SC&A previously noted that the selection criteria 

 1

 Several small changes were made to the criteria to better suit the data. These include changing 

“maintenence” to “maintenance,” the addition of “ironworker”(iron worker already used), “construction,” and 

“concrete” (cement already used). 2

 Remaining 43 CTW claims were returned for another PER (21) and returned prior to evaluation (22). 
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were unnecessarily broad and unspecific. It is possible NIOSH used more definitive selection 

criteria than those listed in PER-011; however, use of any additional criteria should be 

documented. Further evaluation is needed to determine the number of claims that were missed 

due to the improper application of selection criteria.
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5.0 SUBTASK 4: CONDUCT AUDITS OF A SAMPLE-SET OF DOSE 

RECONSTRUCTIONS AFFECTED BY OCAS-PER-011 

According to NIOSH, 69 cases were reworked in behalf of PER-011 and revised to include the 

most current technical guidance. However, selection of a sample of DRs affected by OCASPER-011 for audit by SC&A may at this time be premature and may have to await a 

discussion/resolution by the Subcommittee on Procedures Review regarding findings identified 

by SC&A in Sections 3 and 4 above. In particular, if it is determined that NIOSH improperly 

applied the PER-011 selection criteria, as discussed in Finding #5, the total number of claims 

impacted by this PER may increase. 

On the assumption that the universe of claims remains at 69, SC&A recommends selection of at 

least 2 claims originally completed before May 31, 2005, using an external coworker model and 

revised as a result of PER-011. Additionally, SC&A recommends the selection of at least 2 

CTW claims that were originally completed between May 21, 2005, and August 31, 2006, using 

external coworker data and revised as a result of PER-011.
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6.0 SUMMARY CONCLUSIONS 

In behalf of the four subtasks evaluated under OCAS-PER-011, SC&A identified several 

findings that question the corrective actions taken by NIOSH. A summary of these findings is 

listed below. 

 Finding #1(Conditional): OCAS-PER-011 May Be Restrictive in Identifying All CTWs 

and Unmonitored Workers 

 Finding #2: Date Inconsistencies May Have Missed Non-CTW Coworkers 

 Finding #3: CTW Identification Method Not Specified 

 Finding #4: Not All Cases Returned to NIOSH were Reworked, which May Result in 

Claims Not Being Considered under Other PERs 

 Finding #5: Improper Application of Selected Criteria 

SC&A recommends that the selection of Subtask 4 cases be delayed until the Subcommittee on 

Procedures Review can further investigate SC&A’s findings and concern that NIOSH’s 

corrective actions did not adequately capture all impacted claims.
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REFERENCES 

OCAS-PR-008. 2006. Preparation of Program Evaluation Reports and Program Evaluation 

Plans, Revision 2, NIOSH’s Office of Compensation Analysis and Support, Cincinnati, Ohio. 

December 6, 2006. 

OCAS-PER-011. 2007. K-25 TBD and TIB Revisions, Rev. 00, NIOSH’s Office of 

Compensation Analysis and Support, Cincinnati, Ohio. September 16, 2007. 

OCAS-PER-014. 2007. Construction Trade Workers, Rev. 0, NIOSH’s Office of Compensation 

Analysis and Support, Cincinnati, Ohio. November 28, 2007. 

ORAUT-OTIB-0026. 2005. External Coworker Dosimetry Data for the K-25 Site, Rev. 00, Oak 

Ridge Associated Universities Team, Cincinnati, Ohio. May 31, 2005. 

ORAUT-OTIB-0026. 2005. External Coworker Dosimetry Data for the K-25 Site, Rev. 00 PC1, Oak Ridge Associated Universities Team, Cincinnati, Ohio. July 29, 2005. 

ORAUT-OTIB-0026. 2006. External Coworker Dosimetry Data for the K-25 Site, Rev. 00 PC2, Oak Ridge Associated Universities Team, Cincinnati, Ohio. November 15, 2006. 

ORAUT-OTIB-0052. 2006. Parameters to Consider When Processing Claims for Construction 

Trade Workers, Rev. 00, Oak Ridge Associated Universities Team, Cincinnati, Ohio. August 31, 

2006. 

ORAUT-TKBS-0009-6. 2004. Technical Basis Document for the K-25 Site – Occupational 

External Dose, Rev. 00, Oak Ridge Associated Universities Team, Cincinnati, Ohio. November 

24, 2004. 

SCA-TR-PR2011-0004. 2011. Draft Review of ORAUT-OTIB-0052, Revision 1: Parameters to 

Consider when Processing Claims for Construction Trade Workers, Rev. 00, SC&A, Inc. 

Vienna, Virginia. July 11, 2011. 

SCA-TR-PR2012-0014. A Review of NIOSH’s Program Evaluation Report OCAS-PER-014, 

“Construction Trade Workers,” SC&A, Inc. Vienna, Virginia. March 2012. 
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APPENDIX A: COMPARISON OF ORAUT-TKBS-0009-6 REV. 00 

COWORKER MODEL TO CURRENT GUIDANCE 

The 95th and 50th percentile coworker models presented in ORAUT-TKBS-0009-6 Rev. 00 and 

ORAUT-OTIB-0026 Rev. 00 PC-2 are compared in Tables A-1 and A-2, respectively. ORAUTTKBS-0009-6 Rev. 00 also contained a 99th percentile model; however, since ORAUT-OTIB0026 Rev. 00 PC-2 does not have a 99th percentile model, no comparison was made. 
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Table A-1. Comparison of 95th Percentile Coworker Models 

ORAUT-TKBS0009-6 Rev. 00 

95th Percentile 

Penetrating Dose 

ORAUT-OTIB0026 Rev. 00 

PC-2 95th

Percentile 

Penetrating Dose 

Penetrating 

Dose Percent 

Change 

ORAUT-TKBS0009-6 Rev. 00 

95th Percentile 

Shallow Dose 

ORAUT-OTIB0026 Rev. 00 

PC-2 95th

Percentile 

Shallow Dose 

Shallow 

Dose 

Percent 

Change 

1945 * 1.29 * 0.802 

1946 1.198 1.455 21.5% 3.021 0.884 -70.7% 

1947 0.412 1.015 146.4% 3.005 1.745 -41.9% 

1948 0.712 1.264 77.5% 1.913 0.838 -56.2% 

1949 0.629 1.035 64.5% 3.068 0.47 -84.7% 

1950 2.209 0.841 -61.9% 2.331 0.115 -95.1% 

1951 0.386 1.052 172.5% 1.599 0.582 -63.6% 

1952 0.603 0.951 57.7% 3.656 1.549 -57.6% 

1953 0.765 1.096 43.3% 4.245 2.053 -51.6% 

1954 0.759 0.913 20.3% 3.399 1.088 -68.0% 

1955 0.435 0.835 92.0% 2.98 0.237 -92.0% 

1956 0.451 0.855 89.6% 1.777 0.566 -68.1% 

1957 1.499 1.088 -27.4% 4.806 0.896 -81.4% 

1958 2.035 1.049 -48.5% 5.153 1.325 -74.3% 

1959 1.168 1.245 6.6% 3.929 1.775 -54.8% 

1960 1.598 1.154 -27.8% 4.467 1.078 -75.9% 

1961 0.898 0.942 4.9% 5.744 0.741 -87.1% 

1962 0.133 0.824 519.5% 0.944 0.663 -29.8% 

1963 0.106 0.84 692.5% 0.866 0.619 -28.5% 

1964 0.103 0.841 716.5% 0.581 0.363 -37.5% 

1965 0.236 0.936 296.6% 0.878 0.49 -44.2% 

1966 0.33 0.952 188.5% 2.045 1.188 -41.9% 

1967 0.345 0.928 169.0% 1.711 1.122 -34.4% 

1968 0.575 0.906 57.6% 1.023 0.506 -50.5% 

1969 0.429 0.946 120.5% 3.163 1.106 -65.0% 

1970 0.487 1.041 113.8% 4.222 1.436 -66.0% 

1971 0.343 1.092 218.4% 2.207 0.635 -71.2% 

1972 0.267 1.034 287.3% 0.706 0.381 -46.0% 

1973 0.249 0.871 249.8% 1.219 0.515 -57.8% 

1974 0.777 1.065 37.1% 1.604 0.339 -78.9% 

1975 0.191 0.111 -41.9% 0.713 0.119 -83.3% 

1976 0.963 0.149 -84.5% 1.353 0.069 -94.9% 

1977 1.157 0.089 -92.3% 1.348 0.058 -95.7% 

1978 0.673 0.136 -79.8% 1.763 0.043 -97.6% 

1979 1.231 0.088 -92.9% 2.193 0.063 -97.1% 

1980 2.346 0.145 -93.8% 7.308 0.16 -97.8% 

1981 0.884 0.085 -90.4% 2.212 0.12 -94.6% 

1982 0.607 0.06 -90.1% 1.778 0.425 -76.1% 

1983 0.439 0.06 -86.3% 1.75 0.245 -86.0% 

1984 0.412 0.06 -85.4% 2.117 0.125 -94.1% 

1985 0.497 0.06 -87.9% 3.116 0.105 -96.6% 

1986 0.786 * 0.984 * 

1987 0.631 * 2.563 * 

1988 0.696 * 2.547 * 

Average 84.3% -69.7% 

Min -93.8% -28.5% 

Max 716.5% -97.8% 

* No 95th percentile coworker model for year 
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Table A-2. Comparison of 50th Percentile Coworker Models 

ORAUT-TKBS0009-6 Rev. 00 50th

Percentile 

Penetrating Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

50th Percentile 

Penetrating Dose 

Penetrating 

Dose Percent 

Change 

ORAUT-TKBS0009-6 Rev. 00 

50th Percentile 

Shallow Dose 

ORAUTOTIB-0026 

Rev. 00 PC-2 

50th Percentile 

Shallow Dose 

Shallow 

Dose 

Percent 

Change 

1945 0.475 1.24 161.1% 1.248 0.773 -38.1% 

1946 0.161 0.805 400.0% 0.234 0.065 -72.2% 

1947 0.086 0.78 807.0% 0.359 0.03 -91.6% 

1948 0.096 0.78 712.5% 0.252 0 -100.0% 

1949 0.145 0.78 437.9% 0.379 0.04 -89.4% 

1950 0.186 0.78 319.4% 0.222 0 -100.0% 

1951 0.132 0.78 490.9% 0.326 0.015 -95.4% 

1952 0.118 0.78 561.0% 0.563 0.035 -93.8% 

1953 0.15 0.78 420.0% 0.67 0.095 -85.8% 

1954 0.164 0.78 375.6% 0.544 0 -100.0% 

1955 0.093 0.78 738.7% 0.299 0 -100.0% 

1956 0.14 0.78 457.1% 0.512 0 -100.0% 

1957 0.278 0.78 180.6% 0.681 0 -100.0% 

1958 0.297 0.78 162.6% 0.843 0 -100.0% 

1959 0.192 0.81 321.9% 0.68 0.03 -95.6% 

1960 0.19 0.791 316.3% 0.565 0.024 -95.8% 

1961 0.089 0.778 774.2% 0.399 0.01 -97.5% 

1962 0.032 0.78 2337.5% 0.128 0.022 -82.8% 

1963 0.036 0.78 2066.7% 0.138 0.033 -76.1% 

1964 0.026 0.78 2900.0% 0.121 0.034 -71.9% 

1965 0.065 0.78 1100.0% 0.191 0.066 -65.4% 

1966 0.059 0.78 1222.0% 0.345 0.04 -88.4% 

1967 0.068 0.78 1047.1% 0.251 0.056 -77.7% 

1968 0.079 0.78 887.3% 0.177 0 -100.0% 

1969 0.07 0.78 1014.3% 0.317 0 -100.0% 

1970 0.099 0.78 687.9% 0.397 0.038 -90.4% 

1971 0.066 0.78 1081.8% 0.234 0.01 -95.7% 

1972 0.063 0.779 1136.5% 0.185 0.088 -52.4% 

1973 0.045 0.78 1633.3% 0.196 0 -100.0% 

1974 0.122 0.835 584.4% 0.196 0.008 -95.9% 

1975 0.025 0.062 148.0% 0.076 0.043 -43.4% 

1976 0.125 0.06 -52.0% 0.149 0 -100.0% 

1977 0.326 0.06 -81.6% 0.282 0 -100.0% 

1978 0.097 0.052 -46.4% 0.108 0.013 -88.0% 

1979 0.118 0.06 -49.2% 0.136 0 -100.0% 

1980 0.126 0.06 -52.4% 0.438 0 -100.0% 

1981 0.07 0.06 -14.3% 0.15 0 -100.0% 

1982 0.061 0.06 -1.6% 0.187 0 -100.0% 

1983 0.068 0.06 -11.8% 0.241 0 -100.0% 

1984 0.051 0.06 17.6% 0.274 0 -100.0% 

1985 0.141 0.06 -57.4% 0.353 0 -100.0% 

1986 0.383 * 0.321 * 

1987 0.249 * 0.288 * 

1988 0.243 * 0.264 * 

Average 613.0% -89.8% 

Min -81.6% -100.0% 

Max 2900.0% -38.1% 

* No 50th percentile coworker model for year 
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APPENDIX B: COMPARISON OF ORAUT-OTIB-0026 REV. 00 

COWORKER MODEL TO CURRENT MODEL 

The 95th and 50th percentile coworker models presented in ORAUT-OTIB-0026 Rev. 00 and 

ORAUT-OTIB-0026 Rev. 00 PC-2 are compared in Tables B-1 and B-2, respectively. ORAUTOTIB-0026 Rev. 00 also contained a 99th percentile model; however, since ORAUT-OTIB-0026 

Rev. 00 PC-2 does not have a 99th percentile model, no comparison was made. 
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Table B-1. Comparison of 95th Percentile Coworker Models 

ORAUT-OTIB0026 Rev. 00 

95th Percentile 

Penetrating Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

95th Percentile 

Penetrating Dose 

Penetrating 

Dose Percent 

Change 

ORAUT-OTIB0026 Rev. 00 

95th Percentile 

Shallow Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

95th Percentile 

Shallow Dose 

Shallow 

Dose 

Percent 

Change 

1945 1.305 1.290 -1.1% 0.802 0.802 0.0% 

1946 1.47 1.455 -1.0% 0.884 0.884 0.0% 

1947 1.03 1.015 -1.5% 2.714 1.745 -35.7% 

1948 1.279 1.264 -1.2% 1.325 0.838 -36.8% 

1949 1.05 1.035 -1.4% 0.47 0.47 0.0% 

1950 0.856 0.841 -1.8% 0.115 0.115 0.0% 

1951 1.067 1.052 -1.4% 0.582 0.582 0.0% 

1952 0.966 0.951 -1.6% 1.56 1.549 -0.7% 

1953 1.111 1.096 -1.4% 2.053 2.053 0.0% 

1954 0.928 0.913 -1.6% 1.475 1.088 -26.2% 

1955 0.85 0.835 -1.8% 0.237 0.237 0.0% 

1956 0.87 0.855 -1.7% 0.842 0.566 -32.8% 

1957 1.103 1.088 -1.4% 1.482 0.896 -39.5% 

1958 1.064 1.049 -1.4% 2.526 1.325 -47.5% 

1959 1.26 1.245 -1.2% 1.775 1.775 0.0% 

1960 1.169 1.154 -1.3% 1.078 1.078 0.0% 

1961 0.957 0.942 -1.6% 0.741 0.741 0.0% 

1962 0.839 0.824 -1.8% 0.663 0.663 0.0% 

1963 0.855 0.840 -1.8% 0.619 0.619 0.0% 

1964 0.856 0.841 -1.8% 0.363 0.363 0.0% 

1965 0.951 0.936 -1.6% 0.49 0.49 0.0% 

1966 0.967 0.952 -1.6% 1.189 1.188 -0.1% 

1967 0.943 0.928 -1.6% 1.122 1.122 0.0% 

1968 1.061 0.906 -14.6% 0.366 0.506 38.3% 

1969 0.961 0.946 -1.6% 2.242 1.106 -50.7% 

1970 1.056 1.041 -1.4% 4.103 1.436 -65.0% 

1971 1.107 1.092 -1.4% 2.109 0.635 -69.9% 

1972 1.049 1.034 -1.4% 0.381 0.381 0.0% 

1973 0.886 0.871 -1.7% 0.888 0.515 -42.0% 

1974 1.08 1.065 -1.4% 0.339 0.339 0.0% 

1975 0.126 0.111 -11.9% 0.119 0.119 0.0% 

1976 0.227 0.149 -34.4% 0.041 0.069 68.3% 

1977 0.2 0.089 -55.5% 0.018 0.058 222.2% 

1978 0.151 0.136 -9.9% 0.043 0.043 0.0% 

1979 0.14 0.088 -37.1% 0.059 0.063 6.8% 

1980 0.48 0.145 -69.8% 0.192 0.16 -16.7% 

1981 0.48 0.085 -82.3% 0.398 0.12 -69.8% 

1982 0.65 0.060 -90.8% 0.47 0.425 -9.6% 

1983 0.56 0.060 -89.3% 0.742 0.245 -67.0% 

1984 0.99 0.060 -93.9% 0.37 0.125 -66.2% 

1985 0.48 0.060 -87.5% 0.308 0.105 -65.9% 

Average -17.6% -9.9% 

Min -93.9% -69.9% 

Max -1.0% 222.2% 
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Table B-2. Comparison of 50th Percentile Coworker Models 

ORAUT-OTIB0026 Rev. 00 

50th Percentile 

Penetrating Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

50th Percentile 

Penetrating Dose 

 Penetrating 

Dose 

Percent 

Change 

ORAUT-OTIB0026 Rev. 00 

50th Percentile 

Shallow Dose 

ORAUT-OTIB0026 Rev. 00 

PC-2 50th

Percentile 

Shallow Dose 

 Shallow 

Dose 

Percent 

Change 

1945 1.255 1.24 -1.2% 0.773 0.773 0.0% 

1946 0.82 0.805 -1.8% 0.065 0.065 0.0% 

1947 0.795 0.78 -1.9% 0.03 0.03 0.0% 

1948 0.78 0.78 0.0% 0 0 

1949 0.78 0.78 0.0% 0.055 0.04 -27.3% 

1950 0.78 0.78 0.0% 0 0 

1951 0.78 0.78 0.0% 0.03 0.015 -50.0% 

1952 0.78 0.78 0.0% 0.05 0.035 -30.0% 

1953 0.78 0.78 0.0% 0.11 0.095 -13.6% 

1954 0.78 0.78 0.0% 0 0 

1955 0.78 0.78 0.0% 0 0 

1956 0.78 0.78 0.0% 0 0 

1957 0.78 0.78 0.0% 0 0 

1958 0.78 0.78 0.0% 0 0 

1959 0.825 0.81 -1.8% 0.03 0.03 0.0% 

1960 0.806 0.791 -1.9% 0.024 0.024 0.0% 

1961 0.793 0.778 -1.9% 0.01 0.01 0.0% 

1962 0.78 0.78 0.0% 0.037 0.022 -40.5% 

1963 0.78 0.78 0.0% 0.048 0.033 -31.3% 

1964 0.78 0.78 0.0% 0.049 0.034 -30.6% 

1965 0.78 0.78 0.0% 0.081 0.066 -18.5% 

1966 0.78 0.78 0.0% 0.055 0.04 -27.3% 

1967 0.78 0.78 0.0% 0.071 0.056 -21.1% 

1968 0.78 0.78 0.0% 0 0 

1969 0.78 0.78 0.0% 0 0 

1970 0.78 0.78 0.0% 0.053 0.038 -28.3% 

1971 0.78 0.78 0.0% 0.025 0.01 -60.0% 

1972 0.794 0.779 -1.9% 0.088 0.088 0.0% 

1973 0.78 0.78 0.0% 0 0 

1974 0.85 0.835 -1.8% 0.008 0.008 0.0% 

1975 0.077 0.062 -19.5% 0.043 0.043 0.0% 

1976 0.06 0.06 0.0% 0.008 0 -100.0% 

1977 0.06 0.06 0.0% 0 0 

1978 0.067 0.052 -22.4% 0.013 0.013 0.0% 

1979 0.06 0.06 0.0% 0 0 

1980 0.08 0.06 -25.0% 0.04 0 -100.0% 

1981 0.06 0.06 0.0% 0.04 0 -100.0% 

1982 0.103 0.06 -41.7% 0.177 0 -100.0% 

1983 0.08 0.06 -25.0% 0.16 0 -100.0% 

1984 0.097 0.06 -38.1% 0.103 0 -100.0% 

1985 0.107 0.06 -43.9% 0.073 0 -100.0% 

Average -5.6% -37.2% 

Min -43.9% -100.0% 

Max 0.0% 0.0% 
Effective Date: 

April 24, 2013

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APPENDIX C: COMPARISON OF ORAUT-OTIB-0026 REV. 00 PC-1 

COWORKER MODEL TO CURRENT MODEL 

The 95th and 50th percentile coworker models presented in ORAUT-OTIB-0026 Rev. 00 PC-1 

and ORAUT-OTIB-0026 Rev. 00 PC-2 are compared in Tables C-1 and C-2, respectively. 

During most years, the models are the same yearly coworker dose. The 50th percentile shallow 

dose models do have some differences. 
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Table C-1. Comparison of 95th Percentile Coworker Models 

ORAUT-OTIB0026 Rev. 00 

 PC-1 95th

Percentile 

Penetrating Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

95th Percentile 

Penetrating Dose 

Penetrating 

Dose 

Percent 

Change 

ORAUT-OTIB0026 Rev. 00 

PC-1 95th

Percentile 

Shallow Dose 

ORAUT-OTIB0026 Rev. 00 

PC-2 95th

Percentile 

Shallow Dose 

Shallow 

Dose 

Percent 

Change 

1945 1.29 1.290 0.0% 0.802 0.802 0.0% 

1946 1.455 1.455 0.0% 0.884 0.884 0.0% 

1947 1.015 1.015 0.0% 1.745 1.745 0.0% 

1948 1.264 1.264 0.0% 0.838 0.838 0.0% 

1949 1.035 1.035 0.0% 0.47 0.47 0.0% 

1950 0.841 0.841 0.0% 0.115 0.115 0.0% 

1951 1.052 1.052 0.0% 0.582 0.582 0.0% 

1952 0.951 0.951 0.0% 1.549 1.549 0.0% 

1953 1.096 1.096 0.0% 2.053 2.053 0.0% 

1954 0.913 0.913 0.0% 1.088 1.088 0.0% 

1955 0.835 0.835 0.0% 0.237 0.237 0.0% 

1956 0.855 0.855 0.0% 0.566 0.566 0.0% 

1957 1.088 1.088 0.0% 0.896 0.896 0.0% 

1958 1.049 1.049 0.0% 1.325 1.325 0.0% 

1959 1.245 1.245 0.0% 1.775 1.775 0.0% 

1960 1.154 1.154 0.0% 1.078 1.078 0.0% 

1961 0.942 0.942 0.0% 0.741 0.741 0.0% 

1962 0.824 0.824 0.0% 0.663 0.663 0.0% 

1963 0.84 0.840 0.0% 0.619 0.619 0.0% 

1964 0.841 0.841 0.0% 0.363 0.363 0.0% 

1965 0.936 0.936 0.0% 0.49 0.49 0.0% 

1966 0.952 0.952 0.0% 1.188 1.188 0.0% 

1967 0.928 0.928 0.0% 1.122 1.122 0.0% 

1968 0.906 0.906 0.0% 0.506 0.506 0.0% 

1969 0.946 0.946 0.0% 1.106 1.106 0.0% 

1970 1.041 1.041 0.0% 1.436 1.436 0.0% 

1971 1.092 1.092 0.0% 0.635 0.635 0.0% 

1972 1.034 1.034 0.0% 0.381 0.381 0.0% 

1973 0.871 0.871 0.0% 0.515 0.515 0.0% 

1974 1.065 1.065 0.0% 0.339 0.339 0.0% 

1975 0.111 0.111 0.0% 0.119 0.119 0.0% 

1976 0.149 0.149 0.0% 0.069 0.069 0.0% 

1977 0.089 0.089 0.0% 0.058 0.058 0.0% 

1978 0.136 0.136 0.0% 0.043 0.043 0.0% 

1979 0.088 0.088 0.0% 0.063 0.063 0.0% 

1980 0.145 0.145 0.0% 0.16 0.16 0.0% 

1981 0.085 0.085 0.0% 0.12 0.12 0.0% 

1982 0.06 0.060 0.0% 0.425 0.425 0.0% 

1983 0.06 0.060 0.0% 0.245 0.245 0.0% 

1984 0.06 0.060 0.0% 0.125 0.125 0.0% 

1985 0.06 0.060 0.0% 0.105 0.105 0.0% 

Average 0.0% 0.0% 

Min 0.0% 0.0% 

Max 0.0% 0.0% 
Effective Date: 

April 24, 2013

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Table C-2. Comparison of 50th Percentile Coworker Models 

ORAUT-OTIB0026 Rev. 00 

PC-1 

50th Percentile 

Penetrating Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

50th Percentile 

Penetrating Dose 

Penetrating 

Dose 

Percent 

Change 

ORAUT-OTIB0026 Rev. 00 PC-1 

50th Percentile 

Shallow Dose 

ORAUT-OTIB0026 Rev. 00 PC-2 

50th Percentile 

Shallow Dose 

 Shallow 

Dose 

Percent 

Change 

1945 1.24 1.24 0.0% 0.773 0.773 0.0% 

1946 0.805 0.805 0.0% 0.065 0.065 0.0% 

1947 0.78 0.78 0.0% 0.03 0.03 0.0% 

1948 0.78 0.78 0.0% 0 0 0.0% 

1949 0.78 0.78 0.0% 0.055 0.04 -27.3% 

1950 0.78 0.78 0.0% 0 0 0.0% 

1951 0.78 0.78 0.0% 0.03 0.015 -50.0% 

1952 0.78 0.78 0.0% 0.05 0.035 -30.0% 

1953 0.78 0.78 0.0% 0.11 0.095 -13.6% 

1954 0.78 0.78 0.0% 0 0 0.0% 

1955 0.78 0.78 0.0% 0 0 0.0% 

1956 0.78 0.78 0.0% 0 0 0.0% 

1957 0.78 0.78 0.0% 0 0 0.0% 

1958 0.78 0.78 0.0% 0 0 0.0% 

1959 0.81 0.81 0.0% 0.03 0.03 0.0% 

1960 0.791 0.791 0.0% 0.024 0.024 0.0% 

1961 0.778 0.778 0.0% 0.01 0.01 0.0% 

1962 0.78 0.78 0.0% 0.037 0.022 -40.5% 

1963 0.78 0.78 0.0% 0.048 0.033 -31.3% 

1964 0.78 0.78 0.0% 0.049 0.034 -30.6% 

1965 0.78 0.78 0.0% 0.081 0.066 -18.5% 

1966 0.78 0.78 0.0% 0.055 0.04 -27.3% 

1967 0.78 0.78 0.0% 0.071 0.056 -21.1% 

1968 0.78 0.78 0.0% 0 0 0.0% 

1969 0.78 0.78 0.0% 0 0 0.0% 

1970 0.78 0.78 0.0% 0.053 0.038 -28.3% 

1971 0.78 0.78 0.0% 0.025 0.01 -60.0% 

1972 0.779 0.779 0.0% 0.088 0.088 0.0% 

1973 0.78 0.78 0.0% 0 0 0.0% 

1974 0.835 0.835 0.0% 0.008 0.008 0.0% 

1975 0.062 0.062 0.0% 0.043 0.043 0.0% 

1976 0.06 0.06 0.0% 0.008 0 -100.0% 

1977 0.06 0.06 0.0% 0 0 0.0% 

1978 0.052 0.052 0.0% 0.013 0.013 0.0% 

1979 0.06 0.06 0.0% 0 0 0.0% 

1980 0.06 0.06 0.0% 0.04 0 -100.0% 

1981 0.06 0.06 0.0% 0.04 0 -100.0% 

1982 0.06 0.06 0.0% 0.177 0 -100.0% 

1983 0.06 0.06 0.0% 0.16 0 -100.0% 

1984 0.06 0.06 0.0% 0.103 0 -100.0% 

1985 0.06 0.06 0.0% 0.073 0 -100.0% 

Average 0.0% -26.3% 

Min 0.0% -100.0% 

Max 0.0% 0.0% 
Effective Date: 

April 24, 2013

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APPENDIX D: PERCENT CHANGE COMPARISON BETWEEN 

HISTORICAL COWORKER MODELS AND NEW CTW 

COWORKER MODEL 

Construction Trades Worker (CTW) coworker dose guidance was not available until the issue of 

ORAUT-OTIB-0052. As a result, many EEs with positions that fall in the construction trades 

may have received a coworker dose that underestimates dose when completed with current 

guidance. The K-25 historical coworker dose is compared with the CTW coworker guidance 

from ORAUT-OTIB-0026 Rev. 00 PC-2 in Tables D-1 and D-2, respectively. Red and green

texts are used for added emphasis to negative and positive percent changes, respectively. 
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Table D-1. Percent Change Comparison of Historical 95th Percentile Coworker 

Models and ORAUT-OTIB-0052 CTW Coworker Model 

ORAUT-OTIB-0026 

Rev. 00 PC-2 

ORAUT-TKBS-0009-6 

Rev. 00 

ORAUT-OTIB-0026 

Rev. 00 

ORAUT-OTIB-0026 

Rev. 00 PC-1 

95th % % Change 95th % % Change 95th % % Change 

1945 1.499 ** 1.305 14.9% 1.29 16.2% 

1946 1.731 1.198 44% 1.47 17.8% 1.455 19.0% 

1947 1.115 0.412 171% 1.03 8.3% 1.015 9.9% 

1948 1.463 0.712 105% 1.279 14.4% 1.264 15.7% 

1949 1.143 0.629 82% 1.05 8.9% 1.035 10.4% 

1950 0.871 2.209 -61% 0.856 1.8% 0.841 3.6% 

1951 1.166 0.386 202% 1.067 9.3% 1.052 10.8% 

1952 1.025 0.603 70% 0.966 6.1% 0.951 7.8% 

1953 1.228 0.765 61% 1.111 10.5% 1.096 12.0% 

1954 0.972 0.759 28% 0.928 4.7% 0.913 6.5% 

1955 0.863 0.435 98% 0.85 1.5% 0.835 3.4% 

1956 0.891 0.451 98% 0.87 2.4% 0.855 4.2% 

1957 1.217 1.499 -19% 1.103 10.3% 1.088 11.9% 

1958 1.163 2.035 -43% 1.064 9.3% 1.049 10.9% 

1959 1.436 1.168 23% 1.26 14.0% 1.245 15.3% 

1960 1.309 1.598 -18% 1.169 12.0% 1.154 13.4% 

1961 1.013 0.898 13% 0.957 5.9% 0.942 7.5% 

1962 0.848 0.133 538% 0.839 1.1% 0.824 2.9% 

1963 0.87 0.106 721% 0.855 1.8% 0.84 3.6% 

1964 0.871 0.103 746% 0.856 1.8% 0.841 3.6% 

1965 1.004 0.236 325% 0.951 5.6% 0.936 7.3% 

1966 1.027 0.33 211% 0.967 6.2% 0.952 7.9% 

1967 0.993 0.345 188% 0.943 5.3% 0.928 7.0% 

1968 0.962 0.575 67% 1.061 -9.3% 0.906 6.2% 

1969 1.018 0.429 137% 0.961 5.9% 0.946 7.6% 

1970 1.151 0.487 136% 1.056 9.0% 1.041 10.6% 

1971 1.222 0.343 256% 1.107 10.4% 1.092 11.9% 

1972 1.142 0.267 328% 1.049 8.9% 1.034 10.4% 

1973 0.913 0.249 267% 0.886 3.0% 0.871 4.8% 

1974 1.184 0.777 52% 1.08 9.6% 1.065 11.2% 

1975 0.137 0.191 -28% 0.126 8.7% 0.111 23.4% 

1976 0.191 0.963 -80% 0.227 -15.9% 0.149 28.2% 

1977 0.107 1.157 -91% 0.2 -46.5% 0.089 20.2% 

1978 0.172 0.673 -74% 0.151 13.9% 0.136 26.5% 

1979 0.105 1.231 -91% 0.14 -25.0% 0.088 19.3% 

1980 0.185 2.346 -92% 0.48 -61.5% 0.145 27.6% 

1981 0.101 0.884 -89% 0.48 -79.0% 0.085 18.8% 

1982 0.06 0.607 -90% 0.65 -90.8% 0.06 0.0% 

1983 0.06 0.439 -86% 0.56 -89.3% 0.06 0.0% 

1984 0.06 0.412 -85% 0.99 -93.9% 0.06 0.0% 

1985 0.06 0.497 -88% 0.48 -87.5% 0.06 0.0% 

Average 98.3% -8.7% 10.7% 

Min -92.1% -93.9% 0.0% 

Max 745.6% 17.8% 28.2% 
Effective Date: 

April 24, 2013

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Table D-2. Percent Change Comparison of Historical 50th Percentile Coworker 

Models and ORAUT-OTIB-0052 CTW Coworker Model

ORAUT-OTIB-0026 

Rev. 00 PC-2 

ORAUT-TKBS-0009-6 

Rev. 00 

ORAUT-OTIB-0026 

Rev. 00 

ORAUT-OTIB-0026 

Rev. 00 PC-21 

50th % % Change 50th % % Change 50th % % Change 

1945 1.43 0.475 201% 1.255 13.9% 1.24 15.3% 

1946 0.821 0.161 410% 0.82 0.1% 0.805 2.0% 

1947 0.786 0.086 814% 0.795 -1.1% 0.78 0.8% 

1948 0.78 0.096 713% 0.78 0.0% 0.78 0.0% 

1949 0.78 0.145 438% 0.78 0.0% 0.78 0.0% 

1950 0.78 0.186 319% 0.78 0.0% 0.78 0.0% 

1951 0.78 0.132 491% 0.78 0.0% 0.78 0.0% 

1952 0.78 0.118 561% 0.78 0.0% 0.78 0.0% 

1953 0.78 0.15 420% 0.78 0.0% 0.78 0.0% 

1954 0.78 0.164 376% 0.78 0.0% 0.78 0.0% 

1955 0.78 0.093 739% 0.78 0.0% 0.78 0.0% 

1956 0.78 0.14 457% 0.78 0.0% 0.78 0.0% 

1957 0.78 0.278 181% 0.78 0.0% 0.78 0.0% 

1958 0.78 0.297 163% 0.78 0.0% 0.78 0.0% 

1959 0.828 0.192 331% 0.825 0.4% 0.81 2.2% 

1960 0.801 0.19 322% 0.806 -0.6% 0.791 1.3% 

1961 0.783 0.089 780% 0.793 -1.3% 0.778 0.6% 

1962 0.78 0.032 2338% 0.78 0.0% 0.78 0.0% 

1963 0.78 0.036 2067% 0.78 0.0% 0.78 0.0% 

1964 0.78 0.026 2900% 0.78 0.0% 0.78 0.0% 

1965 0.78 0.065 1100% 0.78 0.0% 0.78 0.0% 

1966 0.78 0.059 1222% 0.78 0.0% 0.78 0.0% 

1967 0.78 0.068 1047% 0.78 0.0% 0.78 0.0% 

1968 0.78 0.079 887% 0.78 0.0% 0.78 0.0% 

1969 0.78 0.07 1014% 0.78 0.0% 0.78 0.0% 

1970 0.78 0.099 688% 0.78 0.0% 0.78 0.0% 

1971 0.78 0.066 1082% 0.78 0.0% 0.78 0.0% 

1972 0.785 0.063 1146% 0.794 -1.1% 0.779 0.8% 

1973 0.78 0.045 1633% 0.78 0.0% 0.78 0.0% 

1974 0.863 0.122 607% 0.85 1.5% 0.835 3.4% 

1975 0.069 0.025 176% 0.077 -10.4% 0.062 11.3% 

1976 0.06 0.125 -52% 0.06 0.0% 0.06 0.0% 

1977 0.06 0.326 -82% 0.06 0.0% 0.06 0.0% 

1978 0.055 0.097 -43% 0.067 -17.9% 0.052 5.8% 

1979 0.06 0.118 -49% 0.06 0.0% 0.06 0.0% 

1980 0.06 0.126 -52% 0.08 -25.0% 0.06 0.0% 

1981 0.06 0.07 -14% 0.06 0.0% 0.06 0.0% 

1982 0.06 0.061 -2% 0.103 -41.7% 0.06 0.0% 

1983 0.06 0.068 -12% 0.08 -25.0% 0.06 0.0% 

1984 0.06 0.051 18% 0.097 -38.1% 0.06 0.0% 

1985 0.06 0.141 -57% 11% -44% 6% 0% 

Average 616.5% -4.6% 1.1% 

Min -81.6% -43.9% 0.0% 

Max 2900.0% 13.9% 15.3%