Memo to DRSC – Re: FMPC DR 1 SC&A – June 23, 2015 

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

MEMO 

TO: Dose Reconstruction Subcommittee 

FROM: Doug Farver, SC&A 

SUBJECT: Differences in the Dose Reconstruction Methods for the Occupational Medical and 

Internal Doses regarding Feed Materials Production Center (FMPC) Case 

#[Redact] 

DATE: June 23, 2015

The dose reconstruction (DR) by NIOSH and the blind DRs by SC&A-Method A, and SC&AMethod B were discussed during the April 14, 2015, DRSC meeting. The major areas of 

differences between the NIOSH and SC&A occupational medical and internal doses are as 

follows: 

1. Occupational Medical Doses. Both NIOSH and SC&A-Method A used the same 

number and type of x-ray examination for their calculations; 8 PA exams, 1 LAT exam. 

SC&A-Method B assumed 6 PA exams from 1982–1993. NIOSH used the dose values 

shown in Tables 3-7 and 3-8 of ORAUT-TKBS-0017-3, Rev. 01. SC&A-Method A used 

the dose values given in Table A-9 of ORAUT-OTIB-0006 and Method B used the dose 

values in Tables 3-14 through 3-16 of ORAUT-TKBS-0017-3, Rev. 00. Table 1-1 shows 

a comparison of the occupational medical doses. 

Table 1-1. Occupational Medical Dose Comparison 

SC&A-Method A SC&A-Method B NIOSH

#1 SCC 

Chest

(rem)

#2 BCC 

Nose

(rem)

#3 BCC 

Ear

(rem)

#4 SCC 

Scalp

(rem)

#5 SCC 

Forehead

(rem)

Chest

(rem) 

Nose, Ear, 

Scalp, Forehead

(rem)

#1 SCC 

Chest

(rem)

#2 BCC 

Nose

(rem)

#3 BCC 

Ear

(rem)

#4 SCC 

Scalp

(rem)

#5 SCC 

Forehead

(rem)

0.065 0.049 0.041 0.081 0.081 0.131 0.131 0.010 0.009 0.024 0.024 0.012

NIOSH completed the DR for the five skin cancers on July 31, 2012 (Version 2). The 

case was revised by NIOSH (Version 3) with [redact] on August 12, 2014. The SC&A 

blind DR of the 5 cancers was completed January 13, 2014. The effective dates of the 

references cited above are as follows: 

 ORAUT-TKBS-0017-3, Rev. 00, Effective date of February 11, 2004 

 ORAUT-TKBS-0017-3, Rev. 01, Effective date of January 2, 2014 

 ORAUT-OTIB-0006, Rev. 04, Effective date of June 20, 2011 

Although it appears NIOSH used dose values from ORAUT-TKBS-0017-3, Rev. 01, 

2 years before it became effective, the dose values in Tables 3-7 and 3-8 of that report 

appear to be derived using the skin dose guidance in Attachment C of ORAUT-PROC-
Memo to DRSC – Re: FMPC DR 2 SC&A – June 23, 2015 

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

0061, Rev. 03 (March 3, 2010) and the x-ray beam parameters in Table 3-10 of ORAUTTKBS-0017-3, Rev. 00. 

2. Internal Doses. NIOSH assigned internal doses from uranium with recycled uranium 

contaminants and from thorium. SC&A assigned internal doses from uranium with 

recycled uranium contaminants. Table 2-1 shows a comparison of the internal doses. 

Table 2-1. Internal Dose Comparison 

SC&A-Method A SC&A-Method B NIOSH

#1 

SCC 

Chest

(rem)

#2 

BCC 

Nose

(rem)

#3 

BCC 

Ear

(rem)

#4 

SCC 

Scalp

(rem)

#5 SCC 

Forehead

(rem)

Chest 

(rem)

Nose, Ear, 

Scalp, 

Forehead 

(rem)

#1 

SCC 

Chest

(rem)

#2 

BCC 

Nose

(rem)

#3 

BCC 

Ear

(rem)

#4 

SCC 

Scalp

(rem)

#5 SCC 

Forehead

(rem)

Uranium/RU 

Contaminants 0.033 0.034 0.037 0.037 0.037 0.238 0.293 0.019 0.020 0.022 0.022 0.022

Thorium – – – – – – – 0.188 0.214 0.280 0.280 0.280

Thorium Doses. The energy employee (EE) submitted a baseline fecal sample [redact],

1994, that was analyzed for thorium. The EE also had several chest counts from 1985–

1997, which were evaluated for uranium and thorium. All results indicated activity levels 

below the minimum detectable activity (MDA) for thorium-232. NIOSH calculated a 

missed thorium dose based on the MDA value of 0.4 nCi from the EE’s last chest count 

in 1997, and then used IMBA to calculate a chronic inhalation intake from the date of the 

fecal sample until the last chest count in 1997.

Uranium/Recycled Contaminant Doses. Both NIOSH and SC&A-Method A assessed 

acute intakes from fitting the elevated bioassay data. NIOSH calculated fitted intakes 

from a bioassay result on [redact], 1985, of 18 μg/L, and another at the MDL (i.e., 

14 μg/L) on [redact], 1987. SC&A-Method A calculated a fitted intake from the 

18 μg/L result. Both NIOSH and SC&A-Method A calculated a missed uranium internal 

dose using one-half the MDL value and the chronic intake period from [redact], 1982, to 

[redact], 1997. Based in these intakes, both NIOSH and SC&A assessed intakes from 

recycled uranium contaminants. NIOSH choose Type M uranium, while SC&AMethod A selected Type S. 

SC&A-Method B assessed a missed uranium dose (Type S) assuming a chronic intake 

from 1983 to1997.

The key difference between the NIOSH and SC&A-Method A dose calculations is in the 

selection of the radiation weighting factors, and the remainder organ selection and rules. 

NIOSH used ICRP 68 weighting factors and remainder rules. SC&A used 10 CFR 835 

weighting factors and remainder rules. IMBA allows the user to select either ICRP 

default values or CFR default values. The IMBA technical documentation states: 

NOTE for Users in the United States: Radiation protection requirements for 

Licensees of the U.S. Nuclear Regulatory Commission (USNRC) and U.S. 

Department of Energy (DOE) and DOE-contractor employees are given in 
Memo to DRSC – Re: FMPC DR 3 SC&A – June 23, 2015 

NOTICE: This report has been reviewed for Privacy Act information and has been cleared for distribution. 

However, this report is pre-decisional and has not been reviewed by the Advisory Board on Radiation and Worker 

Health for factual accuracy or applicability within the requirements of 42 CFR 82.

DOE's Occupational Radiation Protection, Title 10, Code of Federal 

Regulations, Part 835 - referred to here as "10 CFR 835." The requirements 

under 10 CFR 835 (DOE 1999) differ from the ICRP's current 

recommendations in respect of (1) tissue weighting factors; (2) remainder 

tissues, and; (3) remainder tissue rules. In compliance with 10 CFR 835, 

IMBA Professional provides the User with the appropriate "10 CFR 835 

Default" weighting factors and rules for calculation of committed effective 

dose. This software also provides the "option" of substituting ICRP's 

currently recommended weighting factors and rules - for purposes only of 

comparison and investigation. 

For example, recalculating the SC&A-Method A uranium/recycled contaminant #3 BCC 

Ear dose from Table 2-1 using IMBA with the ICRP default values reduces the dose from 

0.037 rem to 0.017 rem.