DCAS-TIB-0010

Best-Estimate External Dose Reconstruction 

for Glovebox Workers

Report from the Procedures Review Subcommittee

Presented to the

Advisory Board on Radiation and Worker Health

Idaho Falls, Idaho

 

July 16–17, 2013
DCAS-TIB-0010 Summary

• Exposure geometry is a concern for 

claimants who worked with gloveboxes. Under-estimation could 

occur if the claimant wore his/her 

dosimeter on the lapel, due to 

distance differences between the 

source, the organ of interest, and 

the dosimeter.

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DCAS-TIB-0010 Summary (Con’t)

• This TIB provides correction factors for bestestimate DR to organs located in the lower torso 

from photons emanating from gloveboxes when a 

dosimeter is worn on the lapel.

• NIOSH calculated the gamma flux at 30 points 

covering the chest and at 30 points covering the 

abdomen, and then determined the ratio of each 

abdomen flux to each chest flux. The mean ratio 

was then selected as the correction factor.

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DCAS-TIB-0010 Timeline

• December 30, 2005 – NIOSH Issued Revision 2

• June 8, 2006 – SC&A Review (SCA-TR-TASK3-0001)

• August 3, 2007 – SC&A Modified Checklist

• November 7, 2007 – NIOSH Initial Response

• October 14, 2008; March 22, 2011; April 11, 2012; and 

February 5, 2013 – Discussed at Subcommittee 

Meetings; Findings Resolved

• June 18, 2010 – NIOSH Issued Revision 3

• November 8, 2011 – NIOSH Issued Revision 4

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Findings Summary: DCAS-TIB-0010

• 9 Findings in total – complete histories captured in 

the Board Review System (BRS)

– http://app-cinc-dcas.cdc.gov:8106/documents/ 

default.aspx?mode=ASSIGNED 

– Resolution spanned over 6 years (6/2006 to 2/2013)

– 6 findings are Closed

– 3 findings are In Abeyance

• The following slides provide summary information on 

the resolution of each Finding – Details in BRS and 

handout

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DCAS-TIB-0010 Review Findings

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# Finding Resolution

1 The TIB lacks transparency. 

The radioactive source is not 

identified; neither its exact 

dimensions nor location are

given, nor is the thickness of 

the walls presented.

Closed on March 22, 2011.

The requested information was provided in 

Appendix B.

2 Lower torso organs not 

specified.

Closed on April 11, 2012.

The phrase “other cancers that appear in the 

region of those organs” (i.e., stomach, liver, 

bladder, prostate, ovaries, testes, genitalia) was 

added to Section 2.0 to allow for cancers such as 

sarcomas, Hodgkin’s lymphomas, or other 

cancers that might occur anywhere, but would 

only require the adjustment if they occurred in 

the region defined by the specified organs.
DCAS-TIB-0010 Review Findings

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# Finding Resolution

3 Correction factors do not 

represent worst-case 

assumptions.

Closed on October 14, 2008.

The Subcommittee is of the opinion that this is a

NIOSH policy decision and has been handled

appropriately.

4 Analysis is needlessly 

complex.

Closed on October 14, 2008.

This was more of an observation than a finding.
DCAS-TIB-0010 Review Findings

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# Finding Resolution

5 We question the design of 

the analysis that compares 

the particle flux over 

locations on the torso, 

rather than modeling the 

variation of dosimeter 

response with location.

Statuses of these two findings were changed to 

In Abeyance on February 5, 2013.

The Subcommittee agrees with the use of the 

95th percentile instead of the mean for the 

correction factor.

6 We question the 

assumptions made 

concerning the glovebox

model, e.g., wall thickness, 

Lexan window, etc..
Finding TIB-0010-05/06 Details

• Instead of the mean from the 30 by 30 array of 

fluxes, SC&A believed it would be better to compare 

the gamma flux to each organ (e.g., stomach, liver, 

bladder, prostate, ovaries, testes, genitalia) and the 

lapel monitor location.

• Alternatively, it was agreed to utilize the 95th

percentile from the 30 by 30 array of fluxes as a 

claimant-favorable correction factor.

• Using the 95th percentile negated the need for “finetuning” the assumptions utilized by NIOSH.

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DCAS-TIB-0010 Review Findings

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# Finding Resolution

7 We question the use of an 

anatomical illustration of a 

human torso rather than 

the ORNL-developed ICRP 

Reference Man-based 

anthropomorphic 

phantoms.

Closed on October 14, 2008.

Since the SC&A-calculated correction factor (CF)

based on the Hp(10) dose rate was the same as 

the CF calculated using the anatomical 

illustration, the additional work to model the 

ICRP Reference Man is not warranted.

8 The use of the Attila 

software is questioned.

Status changed to In Abeyance on February 5, 

2013.

The Subcommittee agrees with the use of the 

95th percentile, instead of the mean, for the 

correction factor.
DCAS-TIB-0010 Review Findings

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# Finding Resolution

9 The use of Rocky Flats to 

validate the model is 

questionable; Rocky Flats 

data is for glovebox and nonglovebox workers, 

information is lacking 

regarding the radiation 

sources, etc. 

Closed on October 14, 2008.

RFP data was used only as a proof of principle; it 

was not used in the justification of the glovebox

factor.

The RFP data has been removed from DCAS-TIB0010.
Questions?

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