Plaintiff LISA ANN DIXSON represented by DANIEL W. EMERY LEAD ATTORNEY ATTORNEY TO BE NOTICED
Defendant SOCIAL SECURITY ADMINISTRATION COMMISSIONER represented by CHRISTOPHER L. POTTER SOCIAL SECURITY ADMINISTRATION OFFICE OF GENERAL COUNSEL JOHN F. KENNEDY FEDERAL BUILDING LEAD ATTORNEY ATTORNEY TO BE NOTICED
JASON W. VALENCIA SOCIAL SECURITY ADMINISTRATION OFFICE OF GENERAL COUNSEL JOHN F. KENNEDY FEDERAL LEAD ATTORNEY ATTORNEY TO BE NOTICED
NATASHA OELTJEN SOCIAL SECURITY ADMINISTRATION OFFICE OF GENERAL COUNSEL, REGION I ATTORNEY TO BE NOTICED
REPORT AND RECOMMENDED DECISION 
John H. Rich III, United States Magistrate Judge
This Social Security Disability (“SSD”) and Supplemental Security Income (“SSI”) appeal raises the question of whether the administrative law judge supportably found the plaintiff capable of performing past relevant work or, in the alternative, work existing in significant numbers in the national economy. The plaintiff seeks reversal and remand on the bases that the administrative law judge erred in (i) finding that she was capable of performing past relevant work, (ii) failing to evaluate her obesity in accordance with Social Security Ruling 02-1p (“SSR 02-1p”), and (iii) omitting a limitation against exposure to respiratory irritants. See Itemized Statement of Errors Pursuant to Local Rule 16.3 Submitted by Plaintiff (“Statement of Errors”) (ECF No. 11) at 2-6. I find no reversible error and, accordingly, recommend that the court affirm the decision.
Pursuant to the commissioner’s sequential evaluation process, 20 C.F.R. §§ 404.1520, 416.920; Goodermote v. Secretary of Health & Human Servs., 690 F.2d 5, 6 (1st Cir. 1982), the administrative law judge found, in relevant part, that the plaintiff met the insured status requirements of the Social Security Act through September 30, 2011, Finding 1, Record at 22; that she had severe impairments of obesity, chronic obstructive pulmonary disease (“COPD”), anxiety disorder, and affective disorder, Finding 3, id.; that she retained the residual functional capacity (“RFC”) to perform light work as defined in 20 C.F.R. §§ 404.1567(b) and 416.967(b) and was able to lift and carry 10 pounds frequently and 20 pounds occasionally, sit for six hours in an eight-hour workday, stand or walk for two hours in an eight-hour workday, and climb, balance, stoop, kneel, crouch, and crawl occasionally, and was capable of performing the basic mental demands of work, Finding 5, id. at 24; that she was capable of performing past relevant work as a cashier/checker, which did not require the performance of work-related activities precluded by her RFC, Finding 6, id. at 29; that, in the alternative, considering her age (45 years old, defined as a younger individual, on her alleged disability onset date, October 1, 2007), education (limited), work experience (transferability of skills immaterial), and RFC, there were jobs existing in significant numbers in the national economy that she could perform, id. at 30; and that she, therefore, was not disabled from October 1, 2007, through the date of the decision, June 14, 2011, Finding 7, id. at 31. The Appeals Council declined to review the decision, id. at 1-3, making the decision the final determination of the commissioner, 20 C.F.R. §§ 404.981, 416.1481; Dupuis v. Secretary of Health & Human Servs., 869 F.2d 622, 623 (1st Cir. 1989).
The standard of review of the commissioner’s decision is whether the determination made is supported by substantial evidence. 42 U.S.C. §§ 405(g), 1383(c)(3); Manso-Pizarro v. Secretary of Health & Human Servs., 76 F.3d 15, 16 (1st Cir. 1996). In other words, the determination must be supported by such relevant evidence as a reasonable mind might accept as adequate to support the conclusion drawn. Richardson v. Perales, 402 U.S. 389, 401 (1971); Rodriguez v. Secretary of Health & Human Servs., 647 F.2d 218, 222 (1st Cir. 1981).
The administrative law judge reached Step 4 of the sequential evaluation process, at which stage the claimant bears the burden of proving inability to return to past relevant work. 20 C.F.R. §§ 404.1520(f), 416.920(f); Bowen v. Yuckert, 482 U.S. 137, 146 n.5 (1987). At this step, the commissioner must make findings of the plaintiff’s RFC and the physical and mental demands of past work and determine whether the plaintiff’s RFC would permit performance of that work. 20 C.F.R. §§ 404.1520(f), 416.920(f); SSR 82-62, reprinted in West’s Social Security Reporting Service Rulings 1975-1982, at 813.
Alternatively, the administrative law judge reached Step 5 of the sequential evaluation process, at which stage the burden of proof shifts to the commissioner to show that a claimant can perform work other than her past relevant work. 20 C.F.R. §§ 404.1520(g), 416.920(g); Bowen, 482 U.S. at 146 n.5; Goodermote, 690 F.2d at 7. The record must contain substantial evidence in support of the commissioner’s findings regarding the plaintiff’s RFC to perform such other work. Rosado v. Secretary of Health & Human Servs., 807 F.2d 292, 294 (1st Cir. 1986).
A. Step 4 (Past Relevant Work) Determination
The commissioner concedes that the administrative law judge erred at Step 4 in deeming the plaintiff capable of performing past relevant work as a cashier/checker. See Defendant’s Opposition to Plaintiff’s Itemized Statement of Errors (“Opposition”) (ECF No. 12) at 2. However, she contends that the error was harmless because he permissibly found in the ...