March 26, 2018 

DISCLAIMER; This is a working document provided by the Centers for Disease Control and Prevention (CDC) technical support contractor, SC&A, for use in 

discussions with the National Institute for Occupational Safety and Health (NIOSH) and the Advisory Board on Radiation and Worker Health (ABRWH), including its 

Working Groups or Subcommittees. Documents produced by SC&A, such as memorandum, white paper, draft or working documents are not final NIOSH or ABRWH 

products or positions, unless specifically marked as such. This document prepared by SC&A represents its preliminary evaluation on technical issues. 

NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and has been cleared for 

distribution. 

ISSUES RESOLUTION MATRIX FOR ORAUT-OTIB-0034, REVISION 01,

“INTERNAL DOSIMETRY COWORKER DATA FOR X-10”

Finding 

Number Finding Description NIOSH Response Finding Resolution

Rev. 00

Finding 1

The procedure is not complete in terms of 

required data. The document references and uses 

data and procedures from other documents that need 

to be known in order to understand the described 

procedures in OTIB-0034.

1/9/2009: NIOSH explained that it is not 

possible for every NIOSH document to crossreference every other potentially applicable 

document, since has proven to be a dynamic 

process. Additionally, NIOSH/ORAUT has a 

training program, and everyone on their team 

knows what protocol is most current and 

should be used in a given situation.

6/9/2009: Based on this explanation, SC&A

and the SCPR agreed with NIOSH’s response,

and the SCPR closed the finding.

Rev. 00 

Finding 2

The procedure points out that “a chronic 

exposure pattern was assumed.” This may not be 

claimant favorable in many cases at ORNL 

(X-10), considering the fact that numerous 

buildings exist on the site where exact dates of 

operations are not known, and the site depended 

on area health physicists to determine if in-vivo 

monitoring should be done. Thus, identification of 

the workers to apply coworker models to is 

difficult, if not impossible.

4/16/2014: SC&A agrees with the NIOSH response 

and recommends that the finding be closed.

8/13/2009: NIOSH explained that chronic 

exposures are assumed for all coworker studies 

in order to account for many small, acute 

intakes that might have occurred and so that all 

time periods of site operation are covered. 

Because the studies are based on an aggregate 

of all monitored workers rather than individual 

workers, the derived intakes are an 

approximation of the total potential for intakes 

rather than any specific incident. The dose 

reconstructor reviews all information in an 

individual’s file, including work history, job 

title, CATI, and external dose history, in order 

to make an informed professional judgment as 

to whether a particular nuclide should be 

assigned from the coworker study.

2/13/2013: The SCPR tasked SC&A with the

review of NIOSH’s response.

4/16/2014: The SCPR agreed with SC&A’s 

recommendation and closed the finding.
Issues Resolution Matrix for OTIB-0017 2 SC&A – March 26, 2018

NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Finding 

Number Finding Description NIOSH Response Finding Resolution

Rev. 00 

Finding 3

For plutonium Type S, the chronic intake for the 

entire set of years was fitted to the bioassay data 

for the last 3 years (1986 through 1988), and all 

the previous years of much higher values were 

ignored. 

3/9/2009: SC&A recommends that the status of issue 

OTIB-0034-03 be changed to “In Progress.” 

Specifically, SC&A recommends that OTIB-0034 be 

provided with the same detailed explanation as used 

in ORAUT-OTIB-0061 (2007), where the same 

methodology is proposed:

For non-systemic (respiratory and GI tract) organs, 

dose reconstructors should follow these steps:

(1) Run the type M intakes. If this action does not 

result in a POC >50%, then (2) Run the minimizing 

type S intake. If this action still does not yield a POC 

>50%, then (3) Manually fit the coworker bioassay 

data for the time frame of interest for the employee, 

using the assumption of type S material. 

By adding these sentences, NIOSH can take care of 

two issues at the same time: (1) Make clear that the 

intake values for Type S reported in ORAUT-OTIB0034 are only to be used as an underestimate of the 

dose. (2) Use Type S compounds for systemic 

organs, when it is claimant favorable to assume 

Type S, instead of Type M. Presently, ORAUTOTIB-0034 only recommends the use of Type M for 

the Systemic Organs.

OCAS-PER-012 (2007), Evaluation of Highly 

Insoluble Plutonium Compounds, cites X-10 as one 

of the sites where Type Super S is to be considered, 

but there is no mention to possible exposures to Type 

Super S Pu in OTIB-0034. SC&A believes that 

OTIB-0034 should include Type Super S Pu.

Finally, NIOSH should answer why lung-counting 

data were not used to build the coworker model.

3/9/2009: The Type S intake rate is assumed to 

be an underestimate and can only be applied to 

compensable cases. Section 5.2, “Dose 

Assignment,” says: “The calculated intake 

rates for type M material should be used for all 

systemic organs and intake periods. For nonsystemic (respiratory and GI tracts) organs, the 

type S intake rate may only be used as an 

underestimate. If an overestimate or best 

estimate is needed for non-systemic organs, an 

individualized fit to the bioassay data, 

assuming type S material, for the specific work 

period of the Energy Employee being evaluated 

must be performed. Table A-3 provides the 

bioassay data to be used to perform the 

individualized fit.”

11/20/2013: SC&A noted that in Revision 01 

of OTIB-0034, plutonium modeling was 

updated to include best estimate intakes for 

Type S material; 95th percentile intakes were 

added for all nuclides, and Attachment A data 

tables expanded to include information on the 

number of samples and employees used in the 

statistical analysis. Therefore, it was 

recommended that the finding be changed from 

“in abeyance” to “closed.”

2/13/2014: The SCPR accepted SC&A’s 

recommendation and closed the finding.
Issues Resolution Matrix for OTIB-0017 3 SC&A – March 26, 2018

NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Finding 

Number Finding Description NIOSH Response Finding Resolution

Rev. 00 

Finding 4

The assumed and predicted intake fits versus the 

values in the first approximately 5 years are much 

less, and from about 3,800 days to 7,200 days. The 

model fit is much higher, indicating that the 

percentile used for deriving the intake should be 

greater. This would, in turn, be more claimant 

favorable.

8/28/2014: SC&A reevaluated the data and 

concluded that NIOSH’s fit of the early data was 

appropriate. SC&A recommended closing the 

finding.

8/13/2014: NIOSH stated that it is unclear what 

is meant by this comment. In the fit to the early 

data, there are 8 results above the line of fit and 

8 points about equally below, which would 

seem to indicate an adequate fit.

8/28/2014: The SCPR accepted SC&A’s 

recommendation and closed the finding.

Rev. 01 

Finding 1

ORAUT-OTIB-0034 fails to mention/address 

potential exposure to Pu-239 Type SS in its 

coworker model.

4/16/2014: SC&A reviewed Section 5.2 of OTIB0034, Rev. 02, and found that NIOSH adequately 

addressed the issue of considering the potential for 

Type Super S solubility for plutonium and 

recommended that the finding be closed.

2/13/2014: NIOSH indicated that the need to 

consider Type Super S solubility for plutonium 

was addressed in Section 5.2 of OTIB-0034, 

Rev. 02, which was published 1/21/2014, 

shortly after SC&A submitted their review of 

OTIB-0034, Rev. 01. SCPR tasked SC&A with 

the review of the Section 5.2 of Rev. 02.

4/16/2014: The SCPR found SC&A’s 

recommendation acceptable and closed this 

finding.

Rev. 01 

Finding 2

Three of the six values for the 95th percentile 

intake of Pu-239 Type S in Table 5-5 of OTIB0034 are significantly lower than values derived 

by SC&A.

4/16/2014: SC&A reviewed Table 5-5 of OTIB0034, Rev. 02, and found that NIOSH had corrected 

the Type S Pu-239 values and recommended that the 

finding be closed.

2/13/2014: NIOSH stated that the values in 

Table 5-5 have been corrected and updated as 

indicated by SC&A in OTIB-0034, Rev. 02. 

SCPR tasked SC&A with the review of OTIB0034, Table 5-5, Rev. 02.

4/16/2016: The SCPR found SC&A’s 

recommendation acceptable and closed this 

finding.
Issues Resolution Matrix for OTIB-0017 4 SC&A – March 26, 2018

NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Finding 

Number Finding Description NIOSH Response Finding Resolution

Rev. 01 

Finding 3

Guidance for the assignment of the 95th 

percentile intake values to unmonitored workers 

is currently inadequate. Guidance is too vague for 

consistent interpretation by dose reconstructors to 

categorize an unmonitored worker as eligible for a 

95th percentile intake rate.

4/16/2014: SC&A reviewed Section 5.0 of OTIB0034, Rev. 02, and still was not satisfied that the 

guidance was prescriptive enough.

2/13/2014: NIOSH stated that additional 

guidance on assignment of 95th percentile 

intake rates has been added to Section 5.0 of 

OTIB-0034, Rev. 02. Therefore, the SCPR 

tasked SC&A with reviewing the guidance in 

Section 5.0.

8/28/2014: After discussion, it was agreed that 

this finding will be addressed in an 

implementation guide on coworker modeling 

that NIOSH is preparing.

8/28/2014: The SCPR changed the status of the 

finding to “In Abeyance,” awaiting the 

issuance of the implementation guide.

It should be noted that a draft of the coworker 

implementation guide has been published and 

reviewed by the Board. This guide contains the 

following discussion regarding assignment of 

95th percentile dose:

“For workers that are considered to have 

worked in environments with a potential for 

elevated exposure, the 95th percentile of the 

distribution should be used as an upper bound 

of their exposure during the modeled time 

period. Although it could be argued that the job 

categories that fall under this criterion should 

be listed, any attempt to do so might be 

artificially restrictive. This decision is most 

accurately made using the information 

available in the site profiles, the claimant 

interview and other documents that might be in 

the worker’s records. For workers who were 

less likely to be highly exposed and/or were 

intermittently exposed in the workplace, the full 

distribution (i.e., the geometric mean and its 

associated standard distribution if a lognormal 

fit is used) should be used as representative of 

their potential for exposure during the modeled 

period.”

Wording in the draft implementation guide 

appears to adequately address this finding. 

However, the SCPR will need to formally close 

the finding at a future meeting.
Issues Resolution Matrix for OTIB-0017 5 SC&A – March 26, 2018

NOTICE: This document has been reviewed to identify and redact any information that is protected by the Privacy Act 5 USC §552a and has been cleared for distribution.

Finding 

Number Finding Description NIOSH Response Finding Resolution

Rev. 01 

Finding 4

NIOSH’s assumption of ORNL bioassay data as 

representative of a full day (24 hours) of urinary 

excretion is subject to question. The ORISE/CER 

urinalyses data show that for all bioassays, the 

dpm/24-hour activity values are consistently a factor 

of 10 higher than the dpm/sample values. This 

relationship would imply a constant sample volume 

of 140 ml that was analyzed for all nuclides and all 

personnel monitored.

On the assumption that the urinalyses data do not 

consistently reflect the collection of a quantified 24-

hour urine volume from which defined aliquots of 

samples were taken for analysis, these data must be 

questioned.

8/28/2014: NIOSH reviewed and provided a 

copy of the data dictionary (SRDB Ref. ID 

134695, PDF pp. 12–13), which indicated that 

the value in the “dpm/24” column in both the 

“1951 – 1978” and “1979 – 1985” datasets is 

expressed to one decimal place. Within this 

format, the integer value expressed as 

“000000001” is actually the real number value 

“0.1.”

8/28/2014: Based on the evidence provided by 

NIOSH, SC&A and the SCPR agreed that the 

data represented a 24-hour sample, and the

SCPR closed the finding.

CATI = computer-assisted telephone interview; GI = gastrointestinal; ORNL = Oak Ridge National Laboratory; POC = probability of causation; SCPR = Subcommittee for Procedure 

Reviews; SRDB = Site Research Database