ORAUT-OTIB-0023

Assignment of Missed Neutron Doses

Based on Dosimeter Records

Report from the Procedures Review Subcommittee

Presented to the

Advisory Board on Radiation and Worker Health

Idaho Falls, Idaho

 

July 16–17, 2013
ORAUT-OTIB-0023 Summary

• The purpose is to provide information to allow 

dose reconstructors to determine when it is 

appropriate to assign missed neutron doses at DOE 

sites using the nLOD/2 method or an “alternative” 

method.

• Use of the “alternative” method should be applied 

when the missed neutron central estimate (i.e., 

nLOD/2) exceeds 75% of the assigned photon dose 

(i.e., from recorded dosimeter dose + missed 

dose).

2
ORAUT-OTIB-0023 Timeline

• March 7, 2005 – NIOSH Issued Revision 0

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

• September 25, 2007 – NIOSH Initial Response

• October 2, 2007; November 7, 2007; January 7, 2008; 

June 24, 2008 – Discussed at Subcommittee Meetings; 

Findings Resolved

• November 5, 2007 – SC&A and NIOSH held conference 

call to discuss OTIB-0023 findings.

• May 14, 2008 – NIOSH Issued Revision 1, incorporated 

comments from Procedures Review Subcommittee, and 

aligned with OCAS-IG-001.

3
Findings Summary: ORAUT-OTIB-0023

• 8 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 2 years (6/2006 to 6/2008)

– All 8 findings are Closed

• The following slides provide summary information on 

the resolution of each Finding – Details in BRS and 

handout.

4
Findings Summary: ORAUT-OTIB-0023

Many of the findings/resolutions deal with 

OTIB-0023, Rev. 00, Section 6, Condition #1, 

which SC&A believed to be inconsistent with 

OCAS-IG-001:

• IG-001, Section 2.2.2.2.1: “..., when the neutron missed dose 

central estimate (nLOD/2) exceeds 75% of the photon dose 

(dosimeter dose + missed dose), the [neutron] exposure 

should be evaluated to determine if it should be considered 

to be an unmonitored exposure.”

• OTIB-0023, Section 6: “Missed neutron doses do not need to 

be assigned if:

1. The neutron missed dose central estimate (nLOD/2) would exceed 

75% of the photon dose (dosimeter dose + missed dose). 

[Emphasis added.]

5
ORAUT-OTIB-0023 Review Findings

6

# Finding Resolution

1 The procedure lacks clarity by 

failing to provide clear 

definition(s), and is inconsistent 

in its terminology.

Closed on June 24, 2008.

OTIB-0023, Revision 1, addressed this 

finding.

2 For the alternative method, 

detailed information is required 

that will not be readily available 

to the dose reconstructor.

Closed on June 24, 2008.

Rev. 00, Section 6, Condition #1 was 

eliminated by Rev. 01, which resolves 

Finding 2.
ORAUT-OTIB-0023 Review Findings

7

# Finding Resolution

3 References OCAS-IG-001 as the 

basis for its guidance; however, 

guidance contained in OTIB-0023 

and OCAS-IG-001 is inconsistent.

Review Objective 1.4: “Is the 

procedure consistent with all 

other procedures that are part of 

the hierarchy of procedures 

employed by NIOSH for dose 

reconstruction?”

Closed on January 7, 2008.

OTIB-0023, Revision 1 (and IG-001, Rev. 3), 

corrected the inconsistencies between IG001 Section 2.2.2.2.1 and OTIB-0023 

Section 6.

4 It is questionable whether dose 

reconstructors are in a position or 

have the information to make the 

potentially subjective decisions 

required.

Closed on June 24, 2008.

Rev. 00, Section 6, Condition #1 was 

eliminated by Rev. 01, which resolves 

Finding 4.
ORAUT-OTIB-0023 Review Findings

8

# Finding Resolution

5 Refer to Finding OTIB-0023-03 for 

Review Objective 1.4.

Review Objective 4.2: “Does the 

procedure adhere to the 

hierarchical process as defined in 

42 CFR 82.2?”

Closed on January 7, 2008.

The Subcommittee indicated that issue 

OTIB-0023-03 was "Closed," since this 

issue refers to issue OTIB-0023-03, it has 

also been "Closed."
ORAUT-OTIB-0023 Review Findings

9

# Finding Resolution

6 The reconstruction of missed 

neutron doses from “...numerous 

neutron measurements and 

accurate time information” is 

unrealistic.

Closed on June 24, 2008.

Rev. 00, Section 6, Condition #1 was 

eliminated by Rev. 01, thus rendering 

Findings 6, 7, and 8 moot.

7 The regulatory recommendation 

for “striking a balance between 

the need for technical precision 

and process efficiency” has been 

ignored.

8 The generic assumption of a 

neutron-to-photon ratio of 0.75:1 

as a limiting value for the 

application of nLOD/2 is neither 

technically defensible nor claimant 

favorable.
Questions?

10