If you work with an optical assistant (OA), you are responsible for them. The Opticians Act 1989 says: “You may delegate the sale and supply of spectacles but you remain responsible for the whole process.” 

There are restrictions on dispensing to children under 16 or people registered as visually impaired. College guidance says: “You must be on the premises at key stages when you are supervising these sales” (COptom, 2025).