HHS Special Exposure Cohort Designation:

Downey Facility, Los Angeles County, California

 

HHS Designation of Additional Members of the 

Special Exposure Cohort 

under the 

Energy Employees Occupational Illness Compensation Program Act of 2000 

Designating a Class of Employees from 

Downey Facility 

Los Angeles County, California
HHS Special Exposure Cohort Designation:

Downey Facility, Los Angeles County, California

Page 2

I. Designation 

I, Kathleen Sebelius, Secretary of Health and Human Services, designate the class 

of employees defined in Section II of this report for addition to the Special Exposure 

Cohort (SEC), as authorized under the Energy Employees Occupational Illness 

Compensation Program Act of 2000 (EEOICPA), 42 U.S.C. § 7384q.

____July 13, 2010____ __[Signature on file]_______

Date Kathleen Sebelius

II. Employee Class Definition

All employees of the Department of Energy, its predecessor 

agencies, and their contractors and subcontractors who 

worked at the Downey Facility in Los Angeles County, 

California from January 1, 1948 through December 31, 1955, 

for a number of work days aggregating at least 250 work days, 

occurring either solely under this employment or in 

combination with work days within the parameters established 

for one or more other classes of employees included in the 

Special Exposure Cohort.

III. Designation Criteria and Recommendations

Pursuant to 42 U.S.C. § 7384q, for the class defined in Section II of this report, the 

Secretary has determined, and the Advisory Board on Radiation and Worker Health 

(Board) has recommended, that

(1) it is not feasible to estimate with sufficient accuracy the radiation dose that the 

class received; and

(2) there is a reasonable likelihood that such radiation dose may have 

endangered the health of members of the class.

The SEC final rule states in 42 C.F.R. § 83.13(c)(1) that it is feasible in two situations 

to estimate the radiation dose that the class received with sufficient accuracy. First, 

the rule states that radiation doses may be estimated with sufficient accuracy if 

NIOSH has established that it has access to sufficient information to estimate the 

maximum radiation dose for every type of cancer for which radiation doses are 

reconstructed that could have been incurred under plausible circumstances by any 

member of the class. Alternatively, radiation doses may be estimated with sufficient 

accuracy if NIOSH has established that it has access to sufficient information to 

estimate the radiation doses of members of the class more precisely than a 

maximum dose estimate.

The Board, pursuant to 42 U.S.C. § 7384q, advised the Secretary to designate the 

class as an addition to the SEC in a letter received by the Secretary on June 16, 

2010.
HHS Special Exposure Cohort Designation:

Downey Facility, Los Angeles County, California

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IV. Designation Findings

Feasibility of Estimating Radiation Doses with Sufficient Accuracy

The Secretary established the feasibility determination for the class of employees 

covered by this report based upon the findings summarized below.

• Principal sources of both internal and external radiation doses for members of 

the NIOSH-proposed class included exposures to fission products, and 

transuranic radionuclides associated with reactor, accelerator, and laboratory

operations. These sources of exposure were also present at Area IV of the 

Santa Susana Field Laboratory (SSFL-Area IV) and the Canoga Avenue 

Facility after Downey Facility operations were transferred to the two sites in 

1955. Downey, SSFL-Area IV, and Canoga were related facilities operated 

by North American Aviation.

• NIOSH previously determined in its evaluations of petitions SEC-00093 and 

SEC-00156 that some SSFL-Area IV workers could have received intakes of 

radioactive materials that went unmonitored from the beginning of the 

covered period for SSFL-Area IV operations in 1955 through the end of 

1964. NIOSH similarly determined in its evaluation of petition SEC-00151 

that the Canoga Avenue Facility also lacked an adequate routine bioassay 

monitoring program during its entire period of operations from 1955 through 

1960. For both sites, limitations in the available data did not allow NIOSH to 

estimate radiation doses with sufficient accuracy. NIOSH therefore 

recommended SEC classes for SSFL-Area IV workers to include the time 

period from January 1, 1955 through December 31, 1964, and for Canoga 

Avenue Facility workers for the period from January 1, 1955 through 

December 31, 1960.

• NIOSH has determined that the Downey Facility was the predecessor site for 

the nuclear operations and health physics practices of North American 

Aviation that were subsequently moved to Canoga and SSFL in 1955. This 

move resulted in a continuation of the Downey health physics practices. 

NIOSH has observed this continuation in the radiological records reviewed 

during its evaluations of petitions SEC-00093, SEC-00151, and SEC-00156 

for the SSFL-Area IV and Canoga Avenue facilities.

• NIOSH has determined that limitations in the available Downey Facility data 

are consistent with the data limitations found for the SSFL-Area IV and 

Canoga Avenue facilities, and such limitations preclude NIOSH from 

estimating Downey Facility radiation doses with sufficient accuracy.

• NIOSH finds that it is not feasible to estimate, with sufficient accuracy, 

internal exposures to fission products and other radionuclides and resulting 

doses for the proposed class of employees at the Downey Facility. NIOSH 

found no evidence of an adequate bioassay monitoring program during DOE 

operational years at the Downey Facility (1948 through 1955). This NIOSH 

finding is consistent with the dose reconstruction infeasibility findings 

beginning in 1955 for the SSFL-Area IV and Canoga Avenue facilities.
HHS Special Exposure Cohort Designation:

Downey Facility, Los Angeles County, California

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Therefore NIOSH does not have access to sufficient personnel monitoring, 

workplace monitoring, or source term data to estimate potential internal 

exposures to fission products and other radionuclides at the Downey Facility 

during the period from January 1, 1948 through December 31, 1955.

• Pursuant to 42 C.F.R. § 83.13(c)(1), NIOSH determined that there is 

insufficient information to either: (1) estimate the maximum radiation dose, for 

every type of cancer for which radiation doses are reconstructed, that could 

have been incurred under plausible circumstances by any member of the 

class; or (2) estimate the radiation doses of members of the class more 

precisely than a maximum dose estimate.

• Although NIOSH found that it is not possible to completely reconstruct 

internal radiation doses for the period from January 1, 1948 through 

December 31, 1955, NIOSH intends to use any internal or external 

monitoring data that may become available for an individual claim (and that 

can be interpreted using existing NIOSH dose reconstruction processes or 

procedures). Dose reconstructions for individuals employed at the Downey 

Facility during the period from January 1, 1948 through December 31, 1955, 

but who do not qualify for inclusion in the SEC, may be performed using 

these data as appropriate.

• NIOSH finds that reconstruction of medical dose is likely to be feasible by 

using claimant-favorable assumptions in the Technical Information Bulletin, 

Dose Reconstruction from Occupationally Related Diagnostic X-Ray 

Procedures (ORAUT-OTIB-0006).

• The Board concurred with the NIOSH evaluation and recommended the 

proposed class for addition to the SEC. 

 Health Endangerment

The Secretary established the health endangerment determination for the class of 

employees covered by this report based upon the findings summarized below.

(1) Pursuant to 42 C.F.R. § 83.13(c)(3), NIOSH established that there is a 

reasonable likelihood that such radiation doses may have endangered the 

health of members of the class. Pursuant to 42 C.F.R. § 83.13(c)(3)(ii), NIOSH 

specified a minimum duration of employment to satisfy this health

endangerment criterion as “having been employed for a number of work days 

aggregating at least 250 work days within the parameters established for this 

class or in combination with work days within the parameters (excluding 

aggregate work day requirements) established for one or more other classes 

of employees in the Cohort.”

(2) NIOSH did not identify any evidence from the petitioners or from other 

resources that would establish that the class was exposed to radiation during 

a discrete incident likely to have involved exceptionally high-level exposures, 

such as a nuclear criticality incident, as defined under 42 C.F.R. § 

83.13(c)(3)(i). 
HHS Special Exposure Cohort Designation:

Downey Facility, Los Angeles County, California

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(3) The Board concurred with NIOSH’s finding that the health of the class may 

have been endangered and defined the class according to the 250-work day 

requirement specified under 42 C.F.R. § 83.13(c)(3)(ii). 

V. Effect and Effective Date of Designation

The Secretary submits this report on the designation of one additional class to the 

SEC for review by Congress, pursuant to 42 U.S.C. §§ 7384l(14)(C)(ii) and 

7384q(c)(2)(A), as amended by the Ronald W. Reagan National Defense 

Authorization Act for Fiscal Year 2005, Pub. L. No. 108-375 (codified as amended in 

scattered sections of 42 U.S.C.). Pursuant to 42 U.S.C. § 7384l(14)(C)(ii), as 

amended by the Ronald W. Reagan National Defense Authorization Act for Fiscal 

Year 2005, Pub. L. No. 108-375 (codified as amended in scattered sections of 42 

U.S.C.), the designation in this report will become effective 30 days after the date of 

this report’s submission to Congress “unless Congress otherwise provides.”

VI. Administrative Review of Designation

The health endangerment determination of the designation provided in this report 

may be subject to an administrative review within HHS, pursuant to 42 C.F.R. § 

83.18(a). On the basis of such a review, if the Secretary decides to expand the class 

of employees covered by this designation, the Secretary would transmit a 

supplementary report to Congress providing the expanded employee class definition 

and the criteria and findings on which the decision was based.