Annex 1 as a legal requirement for the design of processes and production environments is supported and supplemented by DIN EN ISO 14644 with regard to the design and qualification of cleanrooms. This standard is explicitly referenced in some cases and is therefore legally binding for certain content. Other content has established itself independently as "best practice". This presentation is intended as a comparison of both documents to provide an overview of binding requirements, established standard procedures, limits of applicability and current discussions.