What is the ANSI Z80.1 distance refractive power tolerance for powers above 6.50D?

The correct answer is 2%. According to the ANSI Z80.1 standard, when dealing with distance refractive power for lenses with powers above 6.50 diopters, a tolerance of 2% is specified. This percentage indicates how much variation is acceptable from the prescribed lens power. Monitoring refractive power tolerances is vital for ensuring that patients receive the correct prescriptions, which directly impacts visual acuity and overall satisfaction with the corrective lenses. The 2% tolerance ensures that lenses perform effectively while allowing for minor manufacturing variations. Understanding these specifications is crucial for professionals involved in dispensing and manufacturing optical products.