10.2.1 Visual acuity
For the purposes of this publication, visual acuity is defined as a person’s clarity of vision with or without glasses or contact lenses. Where a person does not meet the visual acuity standard at initial assessment, they may be referred for further assessment by an optometrist or ophthalmologist.
Visual acuity should be measured for each eye separately and without optical correction. If optical correction is needed, vision should be retested with appropriate corrective lenses.
Acuity should be tested using a standard visual acuity chart (Snellen or LogMAR chart or equivalent) with five letters on the 6/12 line. Standard charts should be placed six metres from the person tested; otherwise, a reverse chart can be used and viewed through a mirror from a distance of three metres. Other calibrated charts can be used at a minimum distance of three metres. More than two errors in reading the letters of any line is regarded as a failure to read that line. Refer to Figure 15 for management flow chart.
In the case of a private vehicle driver, if the person’s visual acuity is just below that required by the standard but the person is otherwise alert, has normal reaction times and good physical coordination, an optometrist/ophthalmologist can recommend the granting of a conditional licence. The use of contrast sensitivity or other specialised tests may help in the assessment. However, a driver licence will not be issued when visual acuity in the better eye is worse than 6/24 for private vehicle drivers.
There is also some flexibility for commercial vehicle drivers depending on the driving task, providing the visual acuity in the driver’s better eye (with or without corrective lenses) is 6/9 or better.
Restrictions on driving may be advised, for example, where glare is a marked problem.