Blindness indicator

An indicator of permanent blindness. An individual is permanently blind if:

• visual acuity on the Snellen Scale after correction by suitable lenses is less than 6/60 in both eyes;
• a field of vision constricted to 10 degrees or less of arc around central fixation in the better eye irrespective of corrected visual acuity (equivalent to 1/100 white test object);
• a combination of visual defects resulting in the same degree of visual impairment as that occurring in the above points.