Whatever the type of machine used, each installation requires periodic wind turbine maintenance inspections. During commissioning, it is important to check the correct functioning of all the equipment and safety systems. It is thus necessary to carry out various shutdown procedures, including emergency procedures. The operator carries out an annual verification of the condition of the shutdown equipment, and each year after commissioning checks the fastening components: mast, blades and flanges. Every year, it also checks the instrumented safety systems. The wind farm maintenance must be carried out by qualified personnel trained in manufacturer procedures and the risks inherent to each type of wind turbine. With existing wind turbines built by different manufacturers, feedback is essential for correct understanding of the risks which can affect the functioning of the machines.