Category 3 Blindness

A classification of severe visual impairment under the World Health Organization's ICD-10 coding for disorders of the visual system (H54). Category 3 covers blindness in which the better eye has presenting visual acuity worse than 1/60 (20/1200 Snellen) but can still perceive light, or a visual field of less than 10 degrees around central fixation. It is one of five WHO categories (0-4 plus "unqualified") used to describe the spectrum from mild vision impairment through total blindness. Category 3 and 4 together are generally referred to as "blindness," while Categories 1-2 describe moderate to severe low vision. Accessibility researchers and clinicians use these categories to report participant vision precisely without relying on colloquial terms like "legally blind," whose definitions vary by jurisdiction.