This SAE Recommended Practice establishes the test procedure, facilities, and instrumentation for determining the noise reduction characteristics of materials commonly installed in ground vehicles, marine, products, and aircraft to reduce noise levels. This document is intended to provide a means of rank ordering materials by utilizing facilities that do not necessarily meet all of the acoustical requirements in ASTM E 90, Laboratory Measurements of Airborne Sound Transmission Loss of Building Partitions. Latitude is permitted in certain test conditions to allow better correlation with in-use acoustical results.