If the claimant’s RFC limitations adversely affect their (unskilled) occupational
                        base, but do not substantially erode it, consider the RFC limitations in the borderline
                        age analysis. Our Social Security Rulings (SSR) provide authoritative information
                        about the impact of certain RFC limitations on the unskilled occupational base. For
                        a summary of RFC considerations that may be relevant to borderline age analysis, see
                        DI 25020.005, DI 25020.010A.3., and DI 25025.030D.
                     If the occupational base erosion is substantial, be careful to select the correct
                        medical-vocational rule. Do not use the RFC to support the borderline age analysis
                        when the occupational base erosion is substantial, because doing so is double weighing.
                     
                     EXAMPLE of double weighing:
                     A claimant is 54 years, seven months of age. The claimant has a 12th grade education,
                        with no transferable skills, and is no longer able to do their PRW. They have a medium
                        RFC with a nonexertional limitation to occasional crouching. In this case, we find
                        that the limitation to only occasional crouching significantly erodes the occupational
                        base of medium work, so we use a light rule as a framework for the determination.
                        Medical-vocational rule 202.14 (closely approaching advanced age) results in a finding
                        of “not
                        disabled,” while medical-vocational rule 202.06 (advanced age) results in a finding of “disabled.” The claimant is within a few days to a few months of attaining a higher age category;
                        therefore, consider whether to use the claimant’s chronological age or the next higher
                        age category. Do not use the RFC limitation to only occasional crouching to support
                        use of the higher age category because we considered the effect of that limitation
                        on the medium occupational base when we determined that a light rule applied as a
                        framework for our determination. Using the RFC limitation to only occasional crouching
                        in this example to support use of a higher age category is double weighing.
                     
                     EXAMPLE
                           without
                           double weighing:
                     A claimant is 54 years, 11 months of age. They have a 12th grade education with unskilled
                        PRW and no direct entry into skilled or semiskilled work. The claimant cannot perform
                        their PRW. They have a light RFC with restricted overhead reaching. Medical-vocational
                        rule 202.13 (closely approaching advanced age) directs a denial, while medical-vocational
                        rule 202.04 (advanced age) directs an allowance. The claimant is within a few days
                        to a few months of attaining a higher age category; therefore, consider whether to
                        use the claimant’s chronological age or the next higher age category. In this case,
                        the additional limitation in overhead reaching does not significantly erode the light
                        occupational base. The overhead reaching limitation affects the light occupational
                        base, but it does not erode the light base so much that a sedentary rule applies as
                        a framework. Using this RFC limitation to support an allowance under the borderline
                        age criteria does not constitute double weighing.
                     
                     Next, look at the impact of the factors.