CFR › Title 42 › Part 436 › §436.53042 CFR §436.530Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy link(a)Definition. The agency must use the definition of blindness that is used in the State plan for AB or AABD.(b)State plan requirement. The State plan must contain the definition of blindness, expressed in ophthalmic measurements.