ARLINGTON HEIGHTS, Ill. - The Air Movement and Control Association International Inc. (AMCA) introduced a new Certified Ratings Program for acoustical duct silencers. The licenses are available under the new program, which officially began Nov. 15, 2003.

Products that can be licensed by AMCA to bear AMCA International's Certified Ratings Seal for the program are prefabricated acoustical duct silencers. This type of silencer is constructed in advance or manufactured in standard assemblies or sections ready for field installation.

According to AMCA, the purpose of the Certified Ratings Program is to give the buyer, specifier, and user assurance that the published ratings of the prefabricated duct silencers are reliable and accurate. AMCA also believes that the program assures manufacturers that competitive ratings are based on standard test methods, procedures, and are subject to check by impartial authority.

For acoustic duct silencers, certified ratings include dynamic insertion loss, airflow generated noise, and pressure drop.

The method of test used in this program will be ASTM's International Publication E-477-99, Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers.

Testing will be performed in accordance with AMCA International's Publication 1001, Certified Ratings Program Acoustical Duct Silencers, at Intertek in Cortland, N.Y.

For more information on the Certified Ratings Program, visit

Publication date: 12/08/2003