ORAU Team

NIOSH Dose Reconstruction Project

Technical Information Bulletin – Assignment of Environmental 

Internal Doses for Employees Not Exposed to Airborne 

Radionuclides in the Workplace

Document Number:

ORAUT-OTIB-0014

Effective Date: 06/22/2004

Revision No.: 00

Controlled Copy No.:______

Page 1 of 7

Subject Expert: Pamela Olsen

Document Owner

Approval: Signature on File Date: 06/12/2004

Edward F. Maher, Task 5 Manager

Concurrence: Signature on File Date: 06/22/2004

Richard E. Toohey, Project Director

Approval: Signature on File Date: 06/22/2004

James W. Neton, OCAS Health Science Administrator

Supersedes:

None
Effective Date: 06/22/2004 Revision No. 00 Document No. ORAUT-OTIB-0014 Page 2 of 7

RECORD OF ISSUE/REVISIONS

ISSUE 

AUTHORIZATION 

DATE

EFFECTIVE 

DATE

REV. 

NO. DESCRIPTION

Draft 06/09/2004 00-A New technical information bulletin for the 

assignment of environmental internal doses for 

employees not exposed to airborne radionuclides 

in the workplace. Initiated by Pamela Olsen.

Draft 06/11/2004 00-B Incorporates NIOSH review comments. Initiated 

by Pamela Olsen.

06/22/2004 06/22/2004 00 First approved issue. Initiated by Pamela Olsen.
Effective Date: 06/22/2004 Revision No. 00 Document No. ORAUT-OTIB-0014 Page 3 of 7

1.0

The purpose of this Technical Information Bulletin (TIB) is to provide guidance to dose reconstructors 

on (1) when they can assign environmental internal doses rather than potential workplace exposures

to workers, and (2) the methodology for assigning such doses.

PURPOSE

2.0

According to 42 CFR 82 and the Internal Dose Reconstruction Implementation Guideline (NIOSH 

2002), internal radiation doses must be evaluated if there was any potential for internal radiation 

exposure. However, internal radiation doses to some employees were limited to doses from 

inhalation of airborne radionuclides in the ambient environment resulting from site operations or 

contamination, as opposed to localized airborne radionuclides from uncontained radioactive materials 

in the workplace. This TIB describes (1) the considerations dose reconstructors can use in identifying 

such employees, and (2) the methods dose reconstructors can use in assigning such doses to 

individuals.

BACKGROUND

3.0

The following considerations are important when evaluating the appropriateness of assigning 

environmental internal doses as opposed to internal doses from actual or potential workplace 

exposures:

IDENTIFYING EMPLOYEES FOR WHOM ENVIRONMENTAL INTERNAL DOSES ARE 

APPROPRIATE

• Job Description

Attachment A includes a list of common job categories, divided into three categories according 

to the potential for internal radiation exposures from workplace sources. Employees with job 

descriptions that are consistent with Category 1 generally had little potential for exposure, 

. This information is available from various sources including U.S. Department 

of Labor (DOL) records (including information provided by the claimant when completing the 

claim application), U.S. Department of Energy (DOE) records, and the claimant interview. 

Dose reconstructors should use the collective set of information regarding the employee’s job 

when evaluating the appropriateness of assigning environmental internal doses.

although there will be exceptions on individual cases

•

. Category 2 includes job categories that 

often had potential for exposure depending on specific job responsibilities and work locations 

(see below). Category 3 includes job categories that typically had potential for exposure, 

which would suggest that dose reconstructors should not assign environmental doses for

these categories in lieu of dose from workplace sources unless they can determine definitively 

that the individual did not work with or near unconfined radioactive materials.

Work Location. The location to be considered includes both the site and the specific work 

location(s) on the site. At some sites, there was little potential for workplace internal 

exposures at most areas; at other sites, there was such potential at only a few locations. 

Technical Basis Documents (TBDs) for a site, specifically Parts 2, 4 and 5 of the Site Profile, 

contain information on the potential for workplace internal exposures on specific sites and 

areas. In some cases, the TBDs might definitively identify work locations (in combination with 

job descriptions and timeframes, see below) for which there was no potential for internal 

exposures associated with workplace sources and for which it is appropriate to assign 

environmental internal doses.
Effective Date: 06/22/2004 Revision No. 00 Document No. ORAUT-OTIB-0014 Page 4 of 7

• Timeframe

•

. In general, measures to contain radioactive material improved over time 

throughout the DOE Complex. On the other hand, contamination levels might have increased 

in certain facilities, systems, and components over time, increasing the likelihood of exposure. 

By the mid-1980s, DOE policy mandated the implementation of physical controls, such as 

containments, and administrative controls, such as requiring monitoring if contamination 

reached certain levels, to ensure internal radiation exposures were not occurring to the extent 

practicable.

Presence or Absence of Internal Monitoring Data. Although monitoring practices varied from 

site to site and over time, sites were generally more likely to monitor personnel with a potential 

for workplace internal exposures than those with no potential. Monitoring an employee for 

internal exposure, especially routinely or frequently, is often an indicator of potential internal 

radiation exposure. In some cases, however, employees received internal monitoring for 

reasons other than identification of internal exposures (e.g., a termination whole-body count 

performed primarily for recordkeeping or legal purposes). Part 5 of the Site Profiles identifies 

such situations. The presence of positive internal monitoring data is often a clear indicator of 

workplace exposures because detection capabilities were generally not sufficient to detect 

environmental or onsite ambient levels of airborne radioactive materials

•

. (Note: There are 

notable exceptions, such as the detection of global cesium fallout in whole-body counts). 

Coworker Information

Note: The dose reconstructor should evaluate all of the above information collectively to 

determine if the assignment of environmental internal doses is appropriate for a particular 

employee and document the evaluation in the dose reconstruction report.

. If available, dose reconstructors can use coworker internal monitoring 

data or other information to help verify the potential for workplace internal exposures. Such 

data and information might come from completed dose reconstructions, compilations of DOE 

data, interview information, or contact with coworkers who are not Energy Employee 

Occupational Illness Compensation Program Act (EEOICPA) claimants. Overall, the 

robustness of this information will improve over time with the collection and evaluation of

information.

4.0

If dose reconstructors determine (based on the considerations described above) that it is appropriate 

to assign environmental internal doses, they shall base the assignment of such doses on the 

information in Part 4 of the respective Site Profile (together with information in Part 5, as needed). 

This typically involves the assignment of specified intakes for the relevant years and work locations 

and running the Integrated Modules for Bioassay Analysis (IMBA) computer program to determine 

doses. These program runs can occur in advance on a generic or nominal basis to identify 

maximizing scenarios and doses and to permit scaling calculations based on assumed intakes.

ASSIGNING ENVIRONMENTAL INTERNAL DOSES

In some cases, it might be appropriate to assign environmental internal doses for some radionuclides 

but not for others. For example, for a worker with potential exposure to plutonium in the workplace for 

whom an analysis of bioassay data is necessary to assign plutonium doses, it might be appropriate to

assign environmental tritium doses if the worker was exposed to ambient tritium from stack releases 

at other locations on the site.

If calculated environmental internal doses are small (e.g., a few millirem per year) for a particular site 

and set of circumstances (e.g., employment location and timeframe) for clearly noncompensable 

cases, maximizing calculations in advance of the dose reconstructions could permit the assignment of 
Effective Date: 06/22/2004 Revision No. 00 Document No. ORAUT-OTIB-0014 Page 5 of 7

a reasonable maximum nominal value (e.g., 10 mrem/year) for cases that meet these criteria. This 

permits the processing of cases without a detailed assessment of specific intakes if the maximizing 

assumptions result in small doses that will not affect compensability.

If specific work locations on the site are unknown, dose reconstructors should always apply 

maximizing assumptions unless there is clear evidence (e.g., through the job description) that the 

maximum does not apply. As described in the previous section, however, an uncertain work location 

lessens the credibility of assigning environmental doses versus workplace internal doses. If work 

locations varied routinely (e.g., mail carrier, security guard), it might be appropriate to apply a sitewide average, if available, or use a weighted average based on percentage of time in various 

locations.

Calculated annual environmental internal doses that total less than 1 mrem for a specific radiation 

type and energy interval (for photons and electrons), are not required to be included in the Interactive 

RadioEpidemiological Program (IREP) input sheet. For such cases, the dose reconstruction report 

should include appropriate discussions..

5.0

Because this TIB provides guidance on the considerations for assigning environmental internal doses, 

there are no inherent limitations on its use. The guidance contained herein is appropriate for all cases 

that require a decision on whether it might be appropriate to assign environmental internal doses.

APPLICATIONS AND LIMITATIONS
Effective Date: 06/22/2004 Revision No. 00 Document No. ORAUT-OTIB-0014 Page 6 of 7

42 CFR 82, Methods for Radiation Dose Reconstruction Under the Energy Employees Occupational 

Illness Compensation Program Act of 2000; Final Rule, Federal Register/Vol.67, No. 

85/Thursday, May 2, 2002, p 22314.

REFERENCES

NIOSH (National Institute for Occupational Safety and Health), 2002, Internal Dose Reconstruction 

Implementation Guideline, Rev. 0, OCAS-IG-002, Office of Compensation Analysis and 

Support, Cincinnati, Ohio.
Effective Date: 06/22/2004 Revision No. 00 Document No. ORAUT-OTIB-0014 Page 7 of 7

ATTACHMENT A

JOB CATEGORIES AND GENERAL INDICATION OF POTENTIAL 

FOR APPLICATION OF ENVIRONMENTAL INTERNAL EXPOSURES

The purpose of the following examples is to give the dose reconstructor a general idea of the types of 

job categories for which it is more likely that justification exists for assigning environmental internal 

doses because of the absence of a likelihood of exposure to airborne radionuclides from sources in 

the workplace. This list is not all-inclusive, but includes many of the categories most frequently 

provided in DOL records. As discussed in this document, job category (and associated 

responsibilities) is one factor among several that dose reconstructors must evaluate before they can 

determine whether to assign environmental internal doses.

Administrator

Examples of Job Categories that Might Have Little or No Potential for Workplace Internal Exposures

Assistant

Business Systems Specialist

Cafeteria Worker

Checker

Clerk

Computer Specialist

Dispatcher

Draftsman

Groundskeeper

Instructor

Manager

Medical Technician

Office Supervisor

Planner

QA Specialist

Program Analyst

Programmer

Radio Operator

Recruiter

Scheduler

Secretary

Telephone Operator

Biologist

Examples of Job Categories that Generally Have Some Potential for Workplace Internal Exposures 

Depending on Job Specifics

Boilermaker

Bricklayer

Carpenter

Construction Worker

Driver

Electrician

Electronics Technician

Engineer

Equipment Operator

Firefighter

Foreman

Foundry Worker

Heavy Equipment Operator

HP Analyst

Instrument Mechanic

Insulator

Ironworker

Janitor

Laborer

Mechanic

Painter

Patrolman

Photographer

Scientist

Security Guard

Specialist

Storekeeper

Supervisor

Surveyor

Technician

Analytical Chemist

Examples of Job Categories that Probably Have Some Potential for Workplace Internal Exposures

Assembly Worker

Chemical Operator

Fabricator

Glovebox Worker

HP Technician

Machinist

Material Handler

Metallurgist

Millwright

Pipefitter

Plumber

Processor

Production Worker

Radiation Monitor

Radiochemist

Reactor Operator

Steamfitter

Waste Handler

Welder