A VISUAL INSPECTION METHOD TO EVALUATE CLEANLINESS OF NEWLY INSTALLED AIR DUCTS

摘要

Visual inspection is a subjective method to evaluate cleanliness level of duct. Although it is subjective, it is mostly used for estimating necessity to clean a ductwork. The aim of this study was to develop the visual inspection method more objective and to create a procedure for estimation of cleanliness level of an air duct. A visual inspection form and a visual cleanliness scale were applied in recently installed supply air ducts with a panel consisting ten members. The visual scale has been designed for evaluation if the ducts should be cleaned or not. Therefore, it is focused for the amount of accumulated dust from clean to dirty corresponding values <0.1 to 4 g/m~2 measured with the vacuum test method. The developed visual inspection method offers a suitable tool for evaluation of cleanliness especially in new installations. The more objective sampling methods are needed in borderline cases when opinions of customer and client differ.