There is a marked reduction of retinal sensitivity to static luminance targets with increased eccentricity from fixation. The effect of this peripheral field restriction is variable because some racing cars have cockpit designs that also obstruct the driver's peripheral field. In other positions of gaze the head position also has an important effect. In the primary position the monocular individual has a 20–40° peripheral field deficit nasally compared with the temporal side, subject to individual variation, the size of perimetric target used, and the size of the nose. This review is a summary of the relevant aspects of monocularity, which consist of six main areas: the reduction in peripheral visual field, the absence of binocular summation, the possibility of supranormal visual function in a monocular individual, the presence of the blind spot, the absence of stereopsis, and temporary visual loss in the remaining eye. The tribunal was also asked to consider whether the completion of a relatively uneventful season's racing constituted an adequate demonstration of his fitness to compete or whether faster lap times and a higher grid position would increase the risk of a crash resulting from his visual deficit. 4-7 The relevance of such studies when extrapolated to the racetrack was a matter of disagreement. The outcome measure usually applied in studies relating driving performance to visual performance is crash rate, yet many authors have in the past emphasised the minimal part played by driver vision compared with other factors in the causation of domestic road crashes. These studies are unhelpful in defining the visual requirements of the domestic road driver, still less those of a racing driver. However, the literature contains no evidence regarding the visual requirements of a racing driver and all the evidence presented to the commission related to driving on the road or simulated road driving. Motor racing is inherently dangerous 3 and driver vision is critical to the safe operation of a racing car. CAMS argued in defence that he was not reasonably capable of performing the actions required of him in relation to motor racing. Following an unsuccessful appeal, he lodged a complaint in the Human Rights and Equal Opportunities Commission alleging unfair discrimination because of his disability. Shortly after a second medical examination at the end of the season, he was informed that because of his monocularity his licence was revoked forthwith. In his third race he had a false start and for seven laps failed to see and act on the resulting penalty flags, which were being waved on his normally sighted left side. The application was successful and in the following season he competed in 24 practice events and races, finishing towards the back of the field, but completing the season with only one incident. 1Ī CAMS medical practitioner examined an applicant whose right eye had been enucleated at age 2 because of a retinoblastoma. CAMS rules state that monocularity is an absolute bar to the granting of a licence. 2 The required level of stereopsis is undefined and open to interpretation. 1 The field requirement appears to be based historically on Traquair and Roenne's data concerning the size of the normal visual field. The visual requirements for a competition racing driver's licence as stated by the Confederation of Australian Motor Sport (CAMS) are: a visual acuity of 6/9 or better in each eye, a peripheral visual field of 200°, and functional stereopsis.
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