CFR stands for Code of Federal Regulations. It is a codification of general and permanent rules in the USA. This collection of rules and regulations is subdivided into 50 different parts, so-called titles. Title 21 deals with foods and medications. There is a CFR list of chemicals which are approved for the food zone. Stainless steel and glass are generally included in this list. Materials which are included in the CFR list are known as FDA certified materials.