This European Standard specifies safety requirements for the design and construction of unloaders mounted in stationary round silos for the removal of the silage and similar materials. It applies to electrically powered, slowly rotating unloaders which operate on top surface of the stored silage surface.It describes methods for the elimination or reduction of hazards for which specific requirements on unloaders, as defined in 3 and shown in Annex B, are necessary. In addition, it specifies the type of information to be provided by the manufacturer on safe working practices.The document only deals with the hazards generated by the silo unloader and not with