This European Standard specifies requirements and testing for rating and performance of nonresidential Air Handling Units (AHU). It specifies requirements@ classifications and testing of components and sections of ventilation units. For many components and sections it refers to component standards@ but it also specifies restrictions or applications of standards developed for stand-alone components. This European Standard applies to tests in a laboratory and in situ. This European Standard is applicable both for mass produced air handling units and tailor made Air Handling Units. This European Standard applies to AHU and individual sections of AHU with the designed air flow > 250 m3/h. NOTE Units complying with this European Standard can be used in multi dwelling residential buildings.