Division of Compensation Analysis and Support 

(DCAS)

Document No. DCAS-IG-003

Effective Date: 10/05/2010

Revision No. 1

Radiation Exposures Covered for Dose Reconstructions 

under Part B of the Energy Employees Occupational Illness 

Compensation Program Act

Page 1 of 11

Approval: ____Signature on file _______Date: 10/05/2010

 J. W. Neton, Assoc. Dir. for Science

Concurrence: __Signature on file_______Date: 10/05/2010

 S.L. Hinnefeld, Interim Director 

Supersedes:

Revision No. 0

TABLE OF CONTENTS

Section Title Page

1.0 Purpose and Scope.....................................................................3

2.0 Covered Exposure at DOE Facilities................................................3

2.1 Occupational Environmental Exposure....................................4

2.2 Natural Background Exposure...............................................5

2.3 Occupational Medical X-ray Exposure.....................................5

3.0 Covered Exposure at AWE Facilities................................................5

3.1 During the Contract Period...................................................6

3.1.1 Occupational Environmental Exposure

3.1.2 Natural Background Exposure

3.1.3 Occupational Medical X-ray Exposure

3.1.4 Nuclear Navy Exposure

3.2 During the Residual Contamination Period...............................8

3.2.1 Occupational Environmental Exposure

3.2.2 Natural Background Exposure

3.2.3 Occupational Medical X-ray Exposure
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Record of Issue/Revisions

Issue 

Authorization Date

Effective Date Revision

No.

Description

11/05/2007

 10/05/2010

11/05/2007

10/05/2010

0

1

Description of covered exposure 

under EEOICPA

Modified sections 2.0, 2.3, and 3.1.3

to make it clear that, to be included in 

a dose reconstruction, radiation 

exposures must occur at a covered 

facility
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1.0 PURPOSE AND SCOPE

The purpose of this document is to provide guidance as to which sources of 

radiation are to be included in dose reconstructions that are prepared by the 

National Institute for Occupational Safety and Health (NIOSH) under Part B of 

the Energy Employees Occupational Illness Compensation Program Act 

(EEOICPA). Specifically, descriptions are provided of the nature and type of 

occupationally-derived exposure that must be included in the dose reconstruction

of work conducted by or for the U.S. Department of Energy (DOE) or its 

predecessor agencies (e.g., the Energy Research and Development 

Administration, the Atomic Energy Commission and the Manhattan Engineer 

District).

1

 In accordance with the provisions of EEOICPA, these exposures must 

be evaluated for workers at one of two types of facilities, designated as either a 

DOE or an Atomic Weapons Employer facility. Because there are differences in 

the nature and the extent of the exposures that are included in these two facility 

types, this document provides a separate discussion for each.

2.0 COVERED EXPOSURE AT DOE FACILITES

For employees of DOE or its contractors with cancer, the DOE facility definition 

only determines eligibility for a dose reconstruction, which is a prerequisite to a 

compensation decision (except for members of the Special Exposure Cohort). 

The compensation decision for cancer claimants is based on a section of the 

statute entitled “Exposure in the Performance of Duty.” That provision [42 U.S.C. 

§ 7384n(b)] says that an individual with cancer “shall be determined to have 

sustained that cancer in the performance of duty for purposes of the 

compensation program if, and only if, the cancer ... was at least as likely as not 

related to employment at the facility [where the employee worked], as determined 

in accordance with the POC [probability of causation2] guidelines established 

under subsection (c) ...” [42 U.S.C. § 7384n(b)]. Neither the statute nor the 

probability of causation guidelines (nor the dose reconstruction regulation, 42 

CFR Part 82) define “performance of duty” for DOE employees with a covered 

cancer or restrict the “duty” to nuclear weapons work.

The statute also includes a definition of a DOE facility that excludes “buildings, 

structures, premises, grounds, or operations covered by Executive Order No. 

12344, dated February 1, 1982 (42 U.S.C. 7158 note), pertaining to the Naval 

Nuclear Propulsion Program” [42 U.S.C. § 7384l(12)]. While this definition 

excludes Naval Nuclear Propulsion Facilities from being covered under the Act, 

the section of EEOICPA that deals with the compensation decision for covered 

 

1

For purposes of simplicity, all such agencies will be referred to collectively as “DOE” in the 

discussion that follows.

2

The U.S. Department of Labor is ultimately responsible under the EEOICPA for determining the POC.
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employees with cancer [i.e., 42 U.S.C. § 7384n(b), entitled “Exposure in the 

Performance of Duty”] does not contain such an exclusion. Therefore, the 

statute requires NIOSH to include all occupationally-derived radiation exposures 

received at covered facilities in its dose reconstructions for employees at DOE 

facilities, including radiation exposures related to the Naval Nuclear Propulsion 

Program.3 As a result, all internal and external occupational radiation exposures

received at covered facilities are considered valid for inclusion in a dose 

reconstruction. 

These exposures are assessed for each year from the date of initial radiation 

exposure at a covered DOE facility to the date of cancer diagnosis, which is 

established by the Department of Labor. In addition to the exposures associated 

with any radioactive material that was processed at the facility, any dose 

associated with radiation or radiation generating devices that were used at the 

DOE facility during the designated time period must also be reconstructed. This 

includes, but is not limited to, doses from: 1) non-destructive testing devices such 

as radiography units; 2) process or flow gauges that employ radioactive sources; 

3) moisture or density gauges; 4) electrostatic eliminators; and, 5) radiation 

generating laboratory instruments, such as x-ray diffraction units.

2.1 Occupational Environmental Exposure

Environmental exposures due to elevated radiation background levels from DOE 

operations are included in dose reconstructions4. This includes the external 

exposure associated with environmentally deposited radioactivity, as well as the 

intake of radioactive materials due to: 1) the direct inhalation or ingestion of 

material released directly to the environment; or 2) the inhalation or ingestion of 

radioactive material that has been deposited on the ground and resuspended

due to plant operations.

For workers who have been monitored for internal and external exposure via

bioassay samples and personal dosimeter badges, their exposure to 

environmental sources is included in these measurements. As such, a separate 

assessment of this mode of exposure is not necessary in these cases.

Intakes attributable to globally distributed fallout from the above ground testing of 

nuclear weapons are not included in EEOICPA dose reconstructions (see 

attachment A), except at sites where individuals participated in weapons testing 

as part of their work assignment (e.g., the Pacific Proving ground or the Nevada 

Test Site). At weapons testing sites, if baseline measurements of workers are 

available to definitively identify intakes of fallout that occurred prior to 

 

3 Occupationally-derived exposure, defined as that exposure incurred during the performance of 

duty at a DOE facility, does not include certain sources of radiation exposure that are described 

later in this document. 

4

Exposures due to increased natural background radiation, a subset of environmental exposure, 

are discussed in section 2.2.
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employment at the site, these intakes are not considered occupationally-derived 

exposure at the site and are not included in the dose reconstruction.

2.2 Natural Background Exposure

Exposure to internal or external natural background radiation is not included in 

dose reconstructions, unless there is evidence that the natural background was 

increased due to a DOE activity (see attachment A). This is what is known as 

Technologically Enhanced Naturally Occurring Radioactive Material (TENORM). 

Exposure to radon in the workplace would only be considered in a dose 

reconstruction if there was an increase in natural radon levels due to the 

presence of a DOE refined material that included 226Ra. In addition, increased

radon levels due to the existence of structures or tunnels that were required to 

safely test nuclear weapons or components (e.g., tunnels at the Nevada Test 

Site, gravel gerties at IAAP) would be included in a dose reconstruction, while 

increased levels of radon in ordinary sub-surface structures (e.g., basements 

used for office or storage space), not related to the safe testing of nuclear 

weapons, would not be included. 

For bioassay samples that have been collected from site workers and analyzed 

for radionuclides that are naturally present in excreta (e.g., natural uranium in 

urine, natural thorium in feces), the amount of radioactivity naturally present in 

the sample is not considered in the assessment of the dose from site operations. 

If, however, the information is not available to subtract the contribution of the 

natural background component from the sample result, it is an acceptable 

practice, which is favorable to the claimant, to consider the background as part of 

the occupationally-derived exposure.

2.3 Occupational Medical X-ray Exposure

At many DOE facilities, physical examinations were required as a condition of 

employment. Some of these examinations included the use of medical screening 

x-rays. In accordance with 42 C.F.R. pt. 81, external doses received from 

occupational x-ray screening procedures, which were provided to the energy 

employee as a condition of employment and were performed at a covered facility,

are included in dose reconstructions. X-rays performed for diagnostic or 

therapeutic reasons, however, are excluded. Screening x-rays are systematic 

examinations performed on asymptomatic people without history, complaint, 

physical findings, or physician evaluation. Diagnostic x-rays are examinations of 

people who already have suspicious signs or symptoms of a potential condition 

performed after physician evaluation. 

3.0 COVERED EXPOSURE AT AWE FACILITIES

Under EEOICPA, employment at an AWE facility is categorized as either (1) 

during the DOE contract period (i.e., when the AWE was processing or producing 

material that emitted radiation and was used in the production of an atomic 
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weapon), or (2) during the residual contamination period (i.e., periods that 

NIOSH has determined there is the potential for significant residual nuclear 

weapons-related contamination after the period in which weapons-related 

production occurred).

5

 The exposures to be included in a dose reconstruction 

during each of these time periods are not necessarily the same.

6

 Specifically, 

exposures incurred during the residual contamination period are less inclusive 

(i.e., they do not include commercial sources of exposure if the commercial 

sources are distinguishable from the non-commercial sources) than those 

incurred during the DOE contract period. The types of exposures that NIOSH is 

required to include in dose reconstructions during these two defined time periods 

are described below.

3.1 During the Contract Period

For exposures that were incurred during the designated DOE contract period, all 

occupationally-derived radiation exposures at covered facilities must be included 

in dose reconstructions7. These are assessed for each year of exposure from 

the date of initial radiation exposure at a covered AWE facility to the date of 

cancer diagnosis, which is established by the Department of Labor. This not only 

includes the internal and external sources of exposure associated with the 

production of material for the DOE, but also includes radiation exposure related 

to the Naval Nuclear Propulsion Program and any radiation exposure received 

from the production of commercial radioactive products that were concurrently 

manufactured by the AWE facility during the covered period. For example, the 

exposure associated with the commercial production of enriched uranium fuel 

would be reconstructed during the AWE contract period, even though it is 

unrelated to work associated with the production of an atomic weapon. 

In addition, any doses associated with radiation or radiation generating devices 

that were used at the AWE facility during the covered period, even if they were 

not associated with nuclear weapons related work, must also be reconstructed. 

This includes, but is not limited to, doses from: 1) non-destructive testing devices 

such as radiography units; 2) process or flow gauges that employ radioactive 

sources; 3) moisture or density gauges; 4) electrostatic eliminators; and, 5) 

radiation generating laboratory instruments, such as x-ray diffraction units.

3.1.1 Occupational Environmental Exposure

 

5

See 42 U.S.C. § 7384l(3).

6

See 42 U.S.C. § 7384n(c)(4) (defining the doses of radiation to be included in dose 

reconstructions during the residual contamination period).

7 Occupationally-derived exposure, defined as that exposure incurred during the performance of 

duty at an AWE facility, does not include certain sources of radiation exposure that are described 

later in this document.
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Environmental exposures due to elevated radiation background levels from DOE, 

commercial, and other operations are included in dose reconstructions during the 

contract period.

8

 This includes the external exposure associated with 

environmentally deposited radioactivity, as well as the inhalation or ingestion 

intake of radioactive materials due to either: 1) the direct inhalation or ingestion 

of material released from the facility to the environment; or 2) the inhalation or 

ingestion of radioactive material that has been deposited on the ground and 

resuspended due to plant operations. 

For workers who have been monitored for internal and external exposures, via

bioassay samples and personal dosimeter badges, their exposure to 

environmental sources is included in these measurements. A separate 

assessment of this mode of exposure is, therefore, not necessary in this case.

Intakes attributable to globally distributed fallout from the above ground testing of 

nuclear weapons are not included in dose reconstructions at AWE facilities (see 

attachment A).

3.1.2 Natural Background Exposure

Exposure to internal or external natural background radiation is not included in 

dose reconstructions, unless there is evidence that the natural background was 

increased due to either DOE or commercial operations (see attachment A). This 

is what is known as Technologically Enhanced Naturally Occurring Radioactive 

Material (TENORM). Exposure to radon in the workplace would only be 

considered in a dose reconstruction at an AWE facility if there was an increase in 

natural radon levels due to the presence of a refined material that included 226Ra. 

For example, enhanced radon levels due to the production of uranium from 

phosphate rock ore would be a covered exposure at an AWE facility, while 

natural radon present in the workplace at an AWE facility that only processed 

uranium devoid of any progeny would not be covered.

For bioassay samples that have been collected from site workers, and analyzed 

for radionuclides that are naturally present in excreta (e.g., natural uranium in 

urine, natural thorium in feces), the amount of radioactivity present in the sample 

is not considered in the assessment of the dose from site operations. If, 

however, the information is not available to subtract the contribution of the 

natural background component in the samples, it is an acceptable practice, which 

is favorable to the claimants, to consider the background as part of the 

occupationally-derived exposure.

3.1.3 Occupational Medical X-ray Exposure

 

8

Exposures due to increased natural background radiation, a subset of environmental exposure, 

are discussed in section 3.1.2.
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At many AWE facilities, physical examinations were required as a condition of 

employment. Some of these examinations included the use of medical screening 

x-rays. In accordance with 42 C.F.R. pt. 81, external doses received from 

occupational x-ray screening procedures, which were provided to the energy 

employee as a condition of employment and were performed at a covered facility,

are included in dose reconstructions. X-rays performed for diagnostic or 

therapeutic reasons, however, are excluded. Screening x-rays are systematic 

examinations performed on asymptomatic people without history, complaint, 

physical findings, or physician evaluation. Diagnostic x-rays are examinations of 

people who already have suspicious signs or symptoms of a potential condition 

performed after physician evaluation.

3.1.4 Nuclear Navy Related Exposure

It should be noted that under subparagraph A of 42 U.S.C. § 7384n(c)(4), 

radiation associated with the Naval Propulsion Program is specifically excluded 

from the employee’s radiation dose. This exclusion, however, only applies to 

those AWE employees described in 42 U.S.C. § 7384l(3)(B), that is, AWE 

employees who worked during the residual contamination period. Because this 

provision does not apply to AWE employees during the DOE contract period, 

dose reconstructions for this period must include all occupationally-derived 

radiation exposures at a covered AWE facility, including exposure associated 

with work for the nuclear navy propulsion program.

3.2 During the Residual Contamination Period

For employment during the residual contamination period, only the radiation 

exposures defined in 42 U.S.C. § 7384n(c)(4) [i.e., radiation doses received from 

DOE-related work] must be included in dose reconstructions. That is, internal or 

external radiation exposure, associated with commercial sources of exposure, is

not reconstructed. For example, the exposure incurred from the manufacture 

and distribution of commercial uranium and/or thorium products would not be 

reconstructed during the residual contamination period.

Under subparagraph B of 42 U.S.C. § 7384n(c)(4), however, radiation from a 

source that cannot be reliably distinguished from radiation covered under 

subparagraph A (i.e., radiation doses received from DOE related work) is 

considered part of the employee’s radiation dose and must be reconstructed.

During the residual contamination period, doses associated with radiation or 

radiation generating devices that were used at the AWE facility for commercial 

purposes that are distinguishable from the non-commercial sources are not 

included in the dose reconstruction. This includes, but is not limited to, doses 

from: 1) non-destructive testing devices such as radiography units; 2) process or 

flow gauges that employ radioactive sources; 3) moisture or density gauges; 4) 

electrostatic eliminators; and, 5) radiation generating laboratory instruments, 

such as x-ray diffraction units.
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3.2.1 Occupational Environmental Exposure

Environmental exposures due to elevated radiation background levels from

residual contamination due to DOE related activities during the contract period

are included in dose reconstructions during the residual contamination period.

9

 

This includes the external exposure associated with environmentally deposited 

radioactivity, as well as the inhalation or ingestion intake of radioactive materials 

due to: 1) the direct intake of material released from processes in the facility, or 

2) the intake of radioactive material that has been deposited on the ground and 

resuspended due to plant operations. 

For workers who have been monitored for internal and external exposures, 

through bioassay samples and personal dosimeter badges, their exposure to 

environmental sources is included in these measurements. A separate 

assessment of this mode of exposure is, therefore, not necessary in this case.

Intakes attributable to globally distributed fallout from the above ground testing of 

nuclear weapons are not included in dose reconstructions at AWE facilities (see 

Attachment A).

3.2.2 Natural Background Exposure

Exposure to internal or external natural background radiation is not included in 

dose reconstructions, unless there is evidence that the natural background was 

increased due to the presence of residual contamination from DOE activities 

during the contract period. This is what is known as Technologically Enhanced 

Naturally Occurring Radioactive Material (TENORM). For example, exposure to 

radon in the workplace would only be considered TENORM and included in a 

dose reconstruction if there was an increase in natural radon levels due to the 

presence of residual contamination from a DOE-related refined material that was 

elevated in 226Ra. 

For bioassay samples that have been collected for site workers, and analyzed for 

radionuclides that are naturally present in excreta (e.g., natural uranium in urine, 

natural thorium in feces), the amount of radioactivity present in the sample is not 

considered in the assessment of the dose from site operations. If, however, the 

information is not available to subtract the contribution of the natural background 

component in the samples, it is an acceptable practice, which is favorable to the 

claimants, to consider the background as part of the occupationally-derived 

exposure.

3.2.3 Occupational Medical X-ray Exposure

 

9

Exposures due to increased natural background radiation, a subset of environmental exposure, 

are discussed in section 3.2.2.
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Doses from medically required X-rays are not reconstructed during the residual 

contamination period. 
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ATTACHMENT A

Technical Basis for Excluding Fallout and Natural Radiation Background from 

Dose Reconstructions under EEOICPA

The Energy Employees Occupational Illness Compensation Program Act 

(EEOICPA) specifies that the guidelines used in making a probability of 

causation determination shall be:

based on ...the upper 99 percent confidence interval of the probability of 

causation in the radioepidemiological tables published under section 7(b) 

of the Orphan Drug Act (42 U.S.C. 241note), as such tables may be 

updated under section 7(b)(3) of such Act from time to time.10

In the report of the NCI-CDC working group that revised the 1985 

radioepidemiological tables (NCI 1985), the probability of causation (PC) is 

defined as:

risk due to radiation exposure

PC = -------------------------------------------------------

baseline risk + risk due to radiation exposure

The baseline risk included in the probability of causation calculation above was 

established using the cancer incidence of a population that was exposed to a 

variety of carcinogens, including natural background radiation and fallout due to 

atmospheric weapons testing. Because the exposure to natural background and 

fallout is already included in the baseline risk estimate, it would be inappropriate 

to include these exposures a second time in the estimate of risk from radiation 

exposure due to activities that are covered under EEOICPA.

Reference

National Cancer Institute (NCI). Report of the NCI-CDC Working Group to Revise 

the 1985 NIH Radioepidemiological Tables, September 2003, pp. 118.

 

10 See 42 U.S.C. § 7384n(c)(3)(A)