AO Sept solution instructions AO Sept contact lens cleaning solution is one of the most effective cleaners available. It is mainly used for soft contact lenses, though we sometimes will recommend it for hard, RGP, or orthoK contact lenses. It is important to follow these instructions carefully before using AO Sept. AO Sept solution contains hydrogen peroxide which provides the very effecting cleansing for your contact lenses. Over a period of 6 hours in the lens case the hydrogen peroxide is converted to a neutral solution that is then safe for the eyes. It is very important that you always use the contact lens case provided with the AO Sept as the case activates the neutralisation process.