I work for a plant that does film packaging for food products. We received SQF Level 2 certification earlier this year. We are now pursuing SQF Level 3 certification.
Level 3 adds quality management as well as food safety. SQF requires that you do a HACCP analysis for quality similar to what is done for food safety.
We are looking at three areas: quality risks of incoming materials and services, quality risks during our processes, and any other general quality risks that may occur such as dusty roads blowing dust into your plant.
The quality risk analysis is similar to food safety: what is the item, what is the frequency of the risk and severity of the risk (multiply the numbers to get hazard rating), what quality controls are in place based on the hazard rating, do they adequately control the hazard (if not, upgrade the control), and is the control a critical quality control point (last place where you can catch the quality problem).