REACh: identifying the points inspected by a DREAL inspector

An inspector from the DREAL has announced a visit to you, the subject of which is the REACh regulations. You are wondering what points will be checked. The European REACh regulation renews the principle of certain previous procedures, while sometimes modifying the rules of application, and introduces new procedures for the production, import and use of chemical substances. Inspections can be carried out by DREAL inspectors. What are the points checked, and how can we prepare for the checks carried out by the authorities? What documents should be made available?