(1) A school must use the standardized optotype-based distance vision and near vision acuity screening tools approved for each grade as well as the rescreening and referral criteria by grade outlined in Table 1 of this section. When using a screening tool with a single isolated optotype or a single line of optotypes, the tool must include the use of crowding bars or crowding boxes.

(2) A school may use an instrument-based vision screening device in lieu of the optotype-based tools outlined in this section. Referral using instrument-based vision screening devices is determined through the manufacturer's criteria. If the instrument-based screening device does not generate a result for a student, a school must screen that student using the optotype-based tools outlined in this section.