The project supervisor, or where appropriate the client, shall take account of the general principles of prevention concerning safety and health referred to in Directive 89/391/EEC during the various stages of designing and preparing the project, in particular:

• when architectural, technical and/or organizational aspects are being decided, in order to plan the various items or stages of work which are to take place simultaneously or in succession,

• when estimating the period required for completing such work or work stages. Account shall also be taken, each time this appears necessary, of all safety and health plans and of files drawn up in accordance with Article 5 (b) or (c) or adjusted in accordance with Article 6 (c).