Recycled glass over the years has evolved from waste to a sustainable raw material for the glass manufacturing industry. In many areas, recycled glass is the main component of the batch entering the melter.

The increased use of recycled glass introduced a variety of new quality and process challenges, not only in the manufacturing of container glass but also other glasses like float, lighting, and insulation fiberglass. The development of standardized audit methods to inspect recycled glass improved the cullet quality in a way that it can be used without the past problems.