OCAS-PER-014

Construction Trade Workers

Report from the Procedures Review Subcommittee

Presented to the

Advisory Board on Radiation and Worker Health

Redondo Beach, California

 

November 6, 2014

1
The PER Audit Process

As part of SC&A’s support to the Advisory Board, each Program Evaluation Report 

(PER) is subject to a formal review, which includes the following five subtasks:

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

on dose reconstruction (DR).

• Subtask 2: Assess NIOSH’s specific methods for corrective action.

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

potentially affected DRs, and assess the criteria for identifying DRs requiring a 

re-evaluation of doses. 

• Subtask 4 (2-Step Process): Recommend a number of DRs reworked as a result 

of the PER for SC&A’s review, based on specific permutations defined in the 

PER. [A draft PER audit report is submitted to the Procedures Review 

Subcommittee (PRSC) and NIOSH for discussion/resolution of findings.] 

Thereafter, the Subcommittee selects cases for review, and SC&A conducts a 

focused audit of selected DRs.

• Subtask 5: SC&A prepares a supplemental report that contains the results of 

the review of DRs selected under Subtask 4.

2
OCAS-PER-014 Summary

• In 2004, it was determined that some Construction Trades 

Workers (CTWs) at various DOE sites may have been exposed to 

external/internal radiation, but were not monitored . CTWs 

include laborers, mechanics, masons, carpenters, electricians, 

painters, pipefitters, boilermakers, millwrights, sheetmetal

workers, iron workers, insulators and others.

• To address this concern, ORAUT-OTIB-0052 (Technical 

Information Bulletin: Parameters to Consider When Processing 

Claims for Construction Trades Workers) was issued on 

8/31/2006, and provided guidance on assessing radiation 

exposure to CTWs with inadequate monitoring.

3
OCAS-PER-014 Summary (Continued)

• OCAS-PER-014 was issued to re-evaluate claims at the 

following 10 sites where external coworker models had been 

issued prior to 8/31/2006 (i.e., OTIB-0052 publication date): 

- Hanford (internal coworker model also impacted)

- Pacific Northwest National Laboratory (PNNL)

- Kansas City Plant (KCP)

- Los Alamos National Laboratory (LANL)

- Pantex Plant (Pantex)

- Portsmouth Gaseous Diffusion Plant (PGDP)

- Savannah River Site (SRS)

- Weldon Spring Plant (WSP)

- Oak Ridge National Laboratory (X-10)

- Y-12 National Security Complex (Y-12) 

4
OCAS-PER-014 Summary (Continued)

• Four additional sites had external coworker studies published 

prior to OTIB-0052. However, claims at these sites had 

already been re-evaluated using current DR methodology 

(which included OTIB-0052) under other site-specific PERs. 

The four sites, along with their site-specific PERs, are listed 

below:

- Paducah (OCAS-PER-013 issued 11/7/2008)

- Rocky Flats (OCAS-PER-021 issued 8/17/2007)

- Mallinckrodt (OCAS-PER-015 issued 7/31/2007)

- K-25 (OCAS-PER-011 issued 9/26/2007)

5
OCAS-PER-014 Timeline

• 2004 – NIOSH identified that some CTWs at numerous DOE sites 

may have been exposed to radiation, but were not monitored 

• August 31, 2006 – NIOSH issued ORAUT-OTIB-0052, Parameters 

to Consider When Processing Claims for Construction Trades 

Workers

• November 28, 2007 – NIOSH issued OCAS-PER-014, Program 

Evaluation Plan: Construction Trades Workers

• March 16, 2012 – SC&A submitted its draft review of OCAS-PER014 (SCA-TR-PR2012-00014, Rev. 0)

• July 31, 2012; Feb. 13, 2014 – SC&A’s six findings discussed and 

all findings resolved

 

6
Audit of OCAS-PER-014 

Subtask 1: Assess Circumstances that 

Necessitated the Need for the PER

• During facility modification(s) and/or maintenance of major 

systems, CTWs may have been exposed, some of whom were not 

monitored for external and/or internal exposure.

• Exposures of CTWs may be different from other radiation workers 

and the assignment of coworker doses to unmonitored CTWs may 

not be claimant favorable. 

• Empirical data ratios were developed from external and internal 

doses received by monitored CTWs to all monitored workers

(AMWs) using data from seven major DOE sites [SRS, Rocky Flats, 

Y-12, K-25, X-10, INL, and Hanford]. Results of this assessment 

became the basis for NIOSH’s ORAUT-OTIB-0052 guidance.

7
Subtask 1 (Continued): Assess Circumstances 

that Necessitated the Need for the PER

• External Dose. Using empirical data, NIOSH derived:

- Deep dose coworker adjustment factor of 1.4. 

- Shallow dose was adequately bounded by 

AMWs’ doses, and 95th percentile coworker data 

could be used without applying any adjustment 

factor.

• Internal Dose. Only Hanford coworker intake rates 

needed to be multiplied by a factor of 2. For all other 

sites, internal dose should be assessed using the same 

method that is applied to all other workers.

8
Subtask 1 Findings

* A ‘conditional’ finding indicates that SC&A did not have access to original dose data (or an explanation that would clarify 

NIOSH’s assumptions) that would allow SC&A to determine if the data are accurate. This type of finding was established for 

efficiency purposes, when it is determined that a significant level of effort may be required to satisfy SC&A’s concern(s) that 

alternatively could easily be resolved by NIOSH during the resolution process.

9

# Finding Resolution

1 (Conditional*) Deep-dose adjustment factor of 1.4 may not be 

claimant favorable if factor did not account for 

differences in exposure/employment periods in 

any given year between CTWs and AMWs.

NIOSH provided the spreadsheet showing that OTIB0052 was based on Rocky Flats Plant data, and deep 

dose was adjusted for employment periods of less 

than a full year for both CTW and AMW groups. 

2 (Conditional*) Inclusion of CTWs among AMWs may obscure 

dose differences. OTIB-0052 states that 

sometimes the AMW group includes the CTWs 

and in others, it did not; however; OTIB does 

not identify which datasets (i.e., deep dose, 

shallow dose, and/or bioassay data sets) failed 

to separate CTW from AMW data.

The correction is applied to doses in a site-specific 

coworker model, which is based on data for all 

monitored workers. When CTWs are removed from 

the comparison, the ratio favors the CTW if the CTW 

doses are elevated. Also, the 20% threshold criteria 

for adjustment falls inside the margin of uncertainty 

(30%).

3

(Conditional*)

A shallow dose adjustment factor may be 

required if NIOSH failed to adjust CTW shallow 

doses to account for differences in 

employment/exposure periods between CTWs 

and AMWs in any given year.

NIOSH provided the spreadsheet showing that OTIB0052 was based on Rocky Flats Plant data and shallow 

dose was adjusted for employment periods of less 

than a full year for both CTW and AMW groups. 

4 DR guidance in OTIB-0052 for internal dose 

states “. . . the internal dose should be 

determined using the same method that is 

applied to all other workers.” In the absence of 

(1) internal monitoring data for the CTW and 

(2) coworker data, it is unclear what is meant 

by the recommendation. 

This guidance means that the CTWs are treated no 

differently than other workers. The same criteria are 

used to determine potential for intake, and coworker 

values would be the same for all workers.
Subtask 2: Assess Specific Methods for 

Corrective Action

• OCAS-PER-014 was prompted by the issuance of ORAUT-OTIB-0052, 

dated 8/31/2006, which requires multiplying external coworker dose 

by 1.4 for CTWs and, at Hanford, multiplying monitored worker’s 

internal intakes by 2.0.

• Therefore, CTW claims at sites where external coworker studies have 

been issued prior to 8/31/2006 (as cited in Slide #4 above) must be reevaluated.

• To identify all workers that may have been exposed as a member of a 

construction trade, NIOSH performed a search of NOCTS and original 

DR reports using 31 key words (listed in Attachment A of PER-014), 

resulting in the identification of 977 potentially affected claims.

• SC&A reviewed the list of sites with established coworker models and 

key word list and determined that NIOSH’s screening methods appear 

sufficiently inclusive/complete. SC&A had no finding under the Subtask 

2 review.

10
Subtask 3: Evaluate Approach for Identifying 

the Number of DRs Requiring Re-evaluation

• To determine if the 977 potentially affected claims needed a

reworked DR, NIOSH applied the following screening criteria:

- Confirm claim is a CTW, since key word search could not 

verify proper context.

- Verify external coworker dose (or Hanford internal dose) 

was assigned in original DR.

- Screen claims based on ability to raise POC to ≥45% to 

ensure 30 IREP runs are performed, which would be 

triggered by an original POC of 36.8% or 29.0% at Hanford.

- For claims with POC’s less than trigger value, determine if 

any other PERs may increase dose.

11
Subtask 3 Findings

#

12

# Finding Resolution

5 OCAS-PER-014 is incomplete. The 

extent to which NIOSH has screened 

and evaluated the universe of the 

977 claims by means of the abovecited criteria was not discussed in the 

PER. As such, NIOSH has not 

identified the actual number of CTW 

claims (from among the 977 claims) 

that are eligible for the PER’s dose 

adjustment factor(s) and a new DR.

The criteria for determining which claims 

NIOSH would request to be returned are 

not subjective, so it is unclear what value 

the totals add to the PER review. 

Nevertheless, NIOSH provided following:

 977 = total cases 

 52 = returned

 620 = no return necessary

 84 = returned prior to PER evaluation

 221 = return requested for another PER

6 (Conditional) OCAS-PER-014 may be highly 

restrictive in addressing the problem 

of unmonitored CTWs. There is 

uncertainty about the fate of CTW 

claims that had been adjudicated 

before the issuance of a coworker 

model.

The finding assumes CTW DRs completed 

prior to a coworker model would have 

only included environmental and medical 

dose, but would now include a coworker 

dose. This in incorrect. Many claims were 

held for some time awaiting completion of 

a coworker model.
Subtask 4: Recommend a Sample Set of 

Affected DRs for Re-evaluation

• Finding #5 above states NIOSH had not identified the number of 

cases (from 977 potential claims) that will require a reworked DR.

• Regardless of the final number of DRs requiring re-evaluation, SC&A 

recommended that 1 case be selected from each of the following 

10 sites impacted by OCAS-PER-014:

Hanford PNNL

KCP LANL

Pantex Plant PDGP

SRS Weldon Spring Plant 

X-10 Y-12 

 

13
Timeline for SC&A’s Subtask 4 

(Case Audit) Report

• July 31, 2012 PRSC Meeting – SC&A tasked to review 1 case from each of 

the 10 sites impacted by OTIB-0052. Additionally, SC&A tasked to evaluate 

the applicable site TBDs and workbooks to ensure they were properly 

updated to incorporate OTIB-0052’s CTW coworker recommendations. 

During SC&A’s review, it was determined there were no reworked cases at 

4 of the 10 sites. Therefore, SC&A’s review for these 4 sites (i.e., KCP, 

Pantex, PNNL, Weldon Spring) was limited to verification that TBDs and 

workbooks had been updated.

• April 12, 2013 – SC&A submitted its draft Subtask 4 review (Draft SCAPER-14, Subtask 4, Rev. 0). 

• July 18 , 2013, and November 7, 2013, PRSC Meetings – SC&A’s findings 

discussed and all findings resolved. 

14
Subtask 4: Review of Sample Set of DRs 

Affected by PER-014

SC&A received a list of the 977 claims potentially impacted with selection criteria 

applied. Using this list, SC&A generated the following two tables.

Selection Criteria Applied to Potentially Affected Cases

Selection Criteria per Site

15

Result of Selection Criteria Meaning of Designation Cases 

Affected

No Return Necessary NIOSH requested that the case NOT be returned for a new DR 620

Return Requested for Another 

PER NIOSH requested the case be returned based on a different PER 221

Returned to NIOSH NIOSH requested the case be returned for a new DR 52

Returned Prior to Evaluation Case was returned to NIOSH prior to completing the PER evaluation 84

Total 977

Site Total Number 

of Claims

Returned to 

NIOSH

Return Requested 

for Another PER

Returned Prior 

to Evaluation

No Return 

Necessary

Hanford 166 14 80 14 58

PNNL 18 0 8 3 7

KCP 56 5 1 0 50

LANL 49 1 29 9 10

Pantex Plant 1 0 1 0 0

PGDP 112 4 2 4 102

SRS 162 5 61 29 67

Weldon Spring 19 1 1 0 17

X-10 159 10 41 28 80

Y-12 392 24 44 25 299
Subtask 4: Findings Associated with

Execution of Selection Criteria

16

# Finding Resolution

7 SC&A found that many of the cases 

identified as requiring rework did not 

meet all requirements of the selection 

criteria. For example, 5 KCP cases were 

included in the set of 52 cases requiring 

rework. None of these five cases had a 

POC greater than the selection criteria of 

36.8%; therefore, none of the five DRs 

were revised. 

NIOSH stated that they review all 

potential cases <50% to determine if they 

are affected by another PER, etc., in order 

to rework all cases at a particular site at 

the same time. 

8 SC&A noted that some cases were 

returned to NIOSH as a result of OCASPER-014; however, these cases were not 

revised.

NIOSH stated that not all cases are 

returned by DOL, since some are swept 

into a Special Exposure Cohort (SEC) or 

claimant has died and there is no 

survivor. Subcommittee determined that 

NIOSH cannot monitor what cases DOL 

returns and since all returned cases are 

reworked, the finding could be closed.
Subtask 4 Case Reviews

• SC&A performed an audit of 6 reworked cases; one from each 

of the following sites:

- SRS - Portsmouth - Hanford

- X-10 - LANL - Y-12 

• SC&A’s review focused only on those doses impacted by 

OCAS-PER-014, namely assessing accuracy and correctness of 

coworker external doses, and for Hanford, both coworker 

external and internal doses were evaluated.

17
Subtask 4 Case Review Findings

18

# Finding Resolution

9 (SRS);

10 (X-10, Y-12, 

K-25);

11 

(Portsmouth);

16 (Hanford)

OTIB-0052 specifies that the 1.4 

adjustment factor be applied to the 

measured coworker data at the site. 

However, missed and measured doses 

are reported in a single value for each 

percentile of coworker doses at these 

sites; therefore, an adjustment of 1.4 

could not be applied directly.

NIOSH believes that this type of finding 

should have been and in the future should 

be handled during SC&A’s review of the 

technical document (i.e., OTIB, etc.) 

implementing the change. SC&A agreed 

since, in this situation, we have adequate 

empirical evidence to show that the 1.4 

adjustment factor was appropriately applied 

to missed and measured doses. The PRSC 

indicated that the finding should be closed.

12 SC&A questions whether NIOSH is 

planning on revising the one returned 

case for CTW coworker dose at LANL

DOL did not return this case to NIOSH, since 

the worker qualified for SEC status. 

13 The CTW correction factor not applied

to LANL coworker dose. 

This worker had a job title on the list of 

CTWs; however, after reading the CATI 

Report, it was determined the claimant was 

an in-house employee, not a construction 

contractor. 
Subtask 4 Case Review Findings (Continued)

19

# Finding Resolution

14 NIOSH did not apply a dose 

conversion factor (DCF) or 

dosimeter correction factors 

(CFs) to coworker dose.

NIOSH agrees that DCF of 1.244 was not applied to 

unmonitored photon dose. DCF was applied to 

monitored and missed doses.

The dosimeter CF was 1.0 during this period and would 

not impact dose.

NIOSH submitted a file showing the impact of the 

finding on case outcome did not change compensation.

15 Dosimeter uncertainty not 

applied to CTW coworker 

dose at Y-12.

NIOSH stated that measured badge reading should not 

be multiplied by a factor of 1.3, but the value should be 

entered into IREP as a mean of a normal distribution 

with a 30% uncertainty. The TBD was re-evaluated by 

SC&A and it was recommended the findings be closed. 

PRSC agreed.

17 No CTW correction [CTW 

adjustment factor] was 

applied to the unmonitored 

CTW internal dose at 

Hanford. 

Employment was 1944 and intakes were based on air 

monitoring (Battelle-TBD-6000), which were considered 

higher than the OTIB-0052 guidance based on 

urinalysis.

SC&A reassessed case and technical documents and 

recommended closing finding. PRSC agreed.
Subtask 4 Guidance Document/Workbook 

Review Findings

20

# Finding Resolution

18 There does not appear to be 

any Hanford-specific technical 

guidance documents requiring 

the implementation of OTIB0052 for internal coworker 

dose for CTWs.

NIOSH stated that rather than embarking 

on a path of revising the Site Profile, the 

OTIB-0052 requirements are built into the 

dose reconstruction tool, which is used 

by the dose reconstructor. SC&A found 

NIOSH’s response to be acceptable, and 

the PRSC closed the finding.

19 

(Kansas City 

Plant); 

20 (Pantex); 

21 (Weldon 

Spring)

There do not appear to be any 

guidance documents or 

workbooks for implementing 

CTW dose adjustment cited in 

OTIB-0052. 

NIOSH stated that rather than embarking 

on a path of revising the Site Profile, the 

OTIB-52 requirements are built into the 

dose reconstruction tool, which is used 

by the dose reconstructor. SC&A found 

NIOSH’s response to be acceptable, and 

the PRSC closed the finding.
Questions?

21