25.11.2014 Official Journal of the European Union L 337/1 II (Non-legislative acts) REGULATIONS COMMISSION DELEGATED REGULATION (EU) No 1252/2014 of 28 May 2014 supplementing Directive 2001/83/EC of the European Parliament and of the Council with regard to principles and guidelines of good manufacturing practice for active substances for medicinal products for human use (Text with EEA relevance) THE EUROPEAN COMMISSION, Having regard to the Treaty on the Functioning of the European Union, Having regard to Directive 2001/83/EC of the European Parliament and of the Council of 6 November 2001 on the Community code relating to medicinal products for human use (!), and in particular the third paragraph of Article 47 thereof, Whereas: (1) All active substances manufactured in the Union, including active substances intended for export, should be manufactured in accordance with the principles and guidelines of good manufacturing practice for active substances which at present are set out in the technical guidelines on manufacturing of active substances published by the Commission. It is necessary to lay down principles and guidelines of good manufacturing prac- tice for active substances in a legally binding act. (2)  In order to promote the use of harmonised standards at global level, principles and guidelines of good manufac- turing practice for active substances should be laid down in line with the guidelines for active substances estab- lished by the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use. (3)  Principles and guidelines of good manufacturing practice should be set out in relation to all issues, operations and processes that are key to determining the quality of active substances, such as quality management, personnel, premises and equipment, documentation, material management, production, in-process quality controls, packaging, labelling, laboratory controls, returns, complaints and recalls, contracting out and repacka- ging. In order to ensure compliance with those principles and guidelines, the manufacturers of active substances should be required to establish and implement an effective system for managing the quality of those substances. (4)  Personnel in unsanitary conditions, wearing unsuitable clothing or practicing potentially contaminating activities in the manufacturing area may compromise the quality of the active substance. This should be prevented by prac- ticing sanitation and health habits that are appropriate to the manufacturing operations performed. Those prac- tices should be provided for in the quality management system established by the manufacturer of the active substance. (5)  In order to ensure an adequate quality of the active substance, it is necessary to minimise potential contamination and cross-contamination by requiring the use of facilities, production processes and containers designed for this purpose, as well as appropriate contamination controls. () OJL311,28.11.2001,p. 67.