Establishment and implementation of air leakage grade and allowable air leakage volume standard for air ducts

In order to improve the tightness of air ducts, in the revision of JGJ 141-2004 Technical specification for air duct (revised as JGJ/T 141-2017 Technical specification for air duct), establishes specific standards for air leakage grade and allowable air leakage volume of air ducts that are independent of working pressure. The air leakage rate of air ducts is divided into five grades. The fabrication and connection technology of air duct should be determined according to the air leakage grade of air duct during construction. For the selected air ducts according to air leakage grade, air leakage measuring devices or special measuring instruments specified in Appendix of JGJ/T 141-2017 Technical specification for air duct shall be used in acceptance check.