243 F.3d 1375 (Fed. Cir. 2001)
FRANK E. MARINO,  Petitioner,v.OFFICE OF PERSONNEL MANAGEMENT, Respondent.
00-3133
United States Court of Appeals for the Federal Circuit
DECIDED:   March 27, 2001

Appealed from: Merit Systems Protection Board Frank E. Marino, of San Antonio, Texas, pro se.
Doris S. Finnerman, Trial Attorney, Commercial Litigation Branch, Civil Division, Department of Justice, of Washington, DC, for respondent. With her on the brief were David W. Cohen, Director; and Todd M. Hughes, Assistant Director.
Before MAYER, Chief Judge, LOURIE and SCHALL, Circuit Judges.
MAYER, Chief Judge.


1
Frank E. Marino appeals the final decision of the Merit Systems Protection  Board in Docket No. DA844E980317-I-1 (Nov. 1, 1999), denying his  application for disability retirement under the Federal Employees'  Retirement System (FERS). Because the board's decision is contrary to the  language of the governing statute and regulations, we reverse and remand.

Background

2
Marino was employed as a Materials Handler for the Defense Logistics Agency  (DLA) at the Defense Distribution Depot in San Antonio, Texas. On August  15, 1996, he was moved from the warehouse, placed in an administrative  office and given a set of light duties as an accommodation for his alleged  disability (chronic sinusitis and persistent respiratory infections).  Marino remained in the administrative office until he was affected by a  Reduction in Force (RIF) on March 14, 1998. Marino's official position was  terminated as a result of the RIF. On January 30, 1997, he applied for  disability retirement under FERS. The Office of Personnel Management (OPM)  initially denied the request and, on March 11, 1998, issued a final  decision affirming its initial decision. Marino appealed to the board.


3
The administrative judge affirmed OPM's denial of Marino's request. See  Marino v. Office of Pers. Mgmt., No. DA844E980317-I-1 (Dec. 7, 1998)  (initial decision). The administrative judge concluded that Marino failed  to prove by a preponderance of the evidence that his medical problems  rendered him unable to perform useful and efficient service in his  position. The administrative judge first found that the objective medical  evidence does not support a finding that the medical problems are so severe  as to be disabling. Second, he found that DLA provided, and Marino  accepted, an accommodating position in the administrative office. While in  the accommodating position, Marino provided useful and efficient service.  Finally, the administrative judge determined that accommodation would have  continued but for the termination of Marino's position by the RIF. The  initial decision became the final decision of the board on November 1,  1999.

Discussion

4
The scope of our review in an appeal from a decision of the board is  limited. Specifically, we must affirm the decision unless we find it to be  "(1) arbitrary, capricious, an abuse of discretion, or otherwise not in  accordance with law; (2) obtained without procedures required by law, rule,  or regulation having been followed; or (3) unsupported by substantial  evidence." 5 U.S.C. § 7703(c) (1994). Our scope of review of disability  retirement determinations under FERS is even more limited. "[T]his court is  precluded by 5 U.S.C. § 8461(d) from reviewing the factual underpinnings of  physical disability determinations, but may address whether there has been  a `substantial departure from important procedural rights, a  misconstruction of the governing legislation, or some like error going to  the heart of the administrative determination.'" Anthony v. Office of Pers.  Mgmt., 58 F.3d 620, 626 (Fed. Cir. 1995) (quoting Lindahl v. Office of  Pers. Mgmt., 470 U.S. 768, 791 (1985)).


5
Marino claims that he is eligible for disability retirement because,  contrary to the board's finding, DLA failed to accommodate his disability.  The implementing regulations for disability retirement under FERS state  that one of the requirements for disability retirement is that  "[a]ccommodation of the disabling medical condition in the position held  must be unreasonable." 5 C.F.R. § 844.103. Accommodation is defined as "a  reasonable adjustment made to an employee's job or work environment that  enables the employee to perform the duties of the position. Accommodation  may include modifying the worksite; adjusting the work schedule;  restructuring the job; obtaining or modifying equipment or devices;  providing interpreters, readers, or personal assistants; and retraining the  employee." Id. § 844.102. Marino argues that because DLA merely assigned  him an unofficial set of office duties under a personnel loan arrangement,  adjustments were not made to his job or work environment that enabled him  to perform the duties of his official position of Materials Handler.  Therefore, there was no accommodation.


6
We have recently considered this same question for employees serving under  the Civil Service Retirement System (CSRS). See Bracey v. Office of Pers.  Mgmt., 236 F.3d 1356 (Fed. Cir. 2001). The only difference between  disability retirement under CSRS and disability retirement under FERS is  that the preambles to the two regulations state the different eligibility  requirements for the two retirement systems. Compare 5 C.F.R. § 831.1203  with 5 C.F.R. § 844.103. Otherwise, the conditions in the two regulations  are identical. Because of the similarities between the two retirement  systems, commentary on one helps to construe the other. See Harris v. Dep't  of Veterans Affairs, 142 F.3d 1463, 1470 (Fed. Cir. 1998).


7
In Bracey, we held that the adjustment made to the employee's job or work  environment must enable the employee to continue to perform the duties of  his or her official position. 236 F.3d at 1361. A "light-duty assignment  therefore cannot be considered an `accommodation' as that term is used in  the regulations." Id. Here, Marino was never assigned to another position  within the agency. Until his separation, he maintained his official  position of Materials Handler. His assignment to light duties, therefore,  was not an accommodation which allowed him to perform the duties of his  official position.


8
Marino also asserts that the board incorrectly weighed the evidence of his  disability. We may not review the factual underpinnings of physical  disability determinations. Anthony, 58 F.3d at 626. However, he argues that  in determining his disability, the board improperly relied upon his ability  to perform useful and efficient service in his unofficial light duty  position, and not his official position of Materials Handler. This is an  alleged error going to the heart of the administrative determination, which  we may review. See id.


9
The board found that Marino suffers from allergies and respiratory  problems, but concluded that the evidence did not support a finding of  disability. In so concluding, it relied on OPM's finding that Marino was  "providing useful and efficient service in the accommodation position."  Marino at 7 (emphasis added). Marino acknowledged that he was able to  perform any activity in a dust-free (accommodated) environment, but could  not provide useful and efficient service as a Materials Handler. Section  8451 of title 5 of the United States Code requires a finding that the  employee is unable "to render useful and efficient service in the  employee's position." (Emphasis added). As we stated in Bracey, "[a]  `position' in the federal employment system is required to be classified  and graded in accordance with the duties, responsibilities, and  qualification requirements associated with it." 236 F.3d at 1359.  Therefore, any evaluation of useful and efficient service for disability  purposes must be with respect to the employee's official position, not an  unofficial light duty assignment.

Conclusion

10
Accordingly, the decision of the board is reversed and the case is remanded  for further proceedings consistent with this opinion.

REVERSED AND REMANDED
