The revised eyesight standards introduced in 2010 were not determined by the Road Safety Authority. They were introduced through the Road Traffic (Licensing of Drivers) (Amendment) (No. 2) Regulations 2010 (S.I. No. 544 of 2010) which, in turn, represent the transposition into Irish law of European legislation, and specifically of Council Directives 112 and 113 of 2009.
The Directives in question set different standards, including standards for monocular vision, for two groups of licence classes. In the first group — categories A1, A, B, EB, M or W — a competent medical authority must certify that monocular vision has existed for sufficiently long to allow adaptation, and that the field of vision in the eye meets the requirement. After recent loss of vision in one eye, there should be an appropriate adaptation period of a minimum of 6 months, during which driving is not allowed. After this period, driving is only allowed following a favourable opinion from vision experts.
For the second group of licences — categories C1, C, D1, D, EC1, EC, ED1 or ED — after substantial loss of vision in one eye, there should be an appropriate adaptation period of a minimum of six months during which the subject is not allowed to drive. After this period, driving is only allowed after a favourable opinion from vision experts.
The Irish Regulations for both groups follow the requirements of EU legislation. Where an individual has had sufficient time to adapt to monocular vision, they should have no difficulty in receiving the appropriate certification from a qualified practitioner. However, they would need to receive such certification rather than carrying it over from a previous licence.