Sound Transmission Class – Field Testing and Results

This article presents the results of field measurements that were made using a simplified version of the data collection procedure presented in ASTM E336-96, which is used to determine the sound transmission class (STC). This simplified approach provides a less tedious and more efficient method of estimating the sound insulation of partitions and pathways. Several factors are examined, including the effect of speaker type and location, source signal type, room geometry, type of microphone and placement. All of these influence the collection of the transmission loss measurements used in determining STC ratings. The spatial variation and repeatability of measurements on a particular partition and a comparison of results collected on a similar partition under different field conditions are also included to demonstrate a practical application of the STC method.