The Alexandria, VA-based North American Insulation Manufacturers Association (NAIMA), which represents the manufacturers of fiber glass, rock, and slag wool insulation products, has published a new fact sheet which reveals the results of performance testing conducted on cotton duct liner materials. Moisture and corrosion are major considerations when selecting materials for use in HVAC systems, which are subject to high humidity during normal operation. The publication outlines the results of ASTM tests conducted on cotton duct liner, specifically ASTM C 1104 for water vapor sorption and ASTM C 665 for corrosion. The tests were performed at National Voluntary Laboratory Accreditation Program (NAVLAP)-certified laboratories. NAVLAP test results showed that cotton duct liner materials absorbed water and caused corrosion on two types of metals commonly used in HVAC systems. For a free copy of the NAIMA Fact Sheet #73: Moisture & Corrosion Performance of Cotton Duct Liner Materials in HVAC Ducts, order Publication #AH145 through the online Literature Library at (www.naima.org), by phone at 703-684-0084, or by fax at 703-684-0427. For copies of the test reports, contact NAIMA directly. NAIMA has many other free publications and detailed guides on insulation for HVAC systems also available online or in print.