This document defines the test methods and performance characteristics for rigid or semi-rigid non-metallic ductwork which are used for ventilation and air conditioning of buildings. This document does not include flexible ducts such as those made of textiles, non-metallic spiral ductwork or others, which are handled in EN 13180 or ductwork made from insulation duct board, which is handled in EN 13403. Requirements for the air tightness of the ventilation system for non-residential buildings are given in EN 16798 3. For residential buildings, it is essential to apply national rules. This document specifies methods to test rigid or semi-rigid non-metallic ductwork under laboratory conditions. On-site tests are excluded. The test methods and performance characteristics are valid for ventilation ducts with circular, rectangular or other cross sections.