STC and IIC Performance Testing

Testing the quality of a wall and/or floor for sound transmission and/or impact isolation is often necessary to evaluate the design or the installation. These tests are not only important to ensure the acoustic performance of your materials, but also to inspect the installation of products such as windows, operable partitions, and floating floors, to make sure that they have been installed correctly.

The American Society for Testing and Materials (ASTM) provides methods that can be included in a project manual as part of a material specification.  Operable walls, windows, absorptive treatments, and impact isolation systems can all be tested by procedures outlined under these ASTM Standards.

Sound Transmission Class
The sound transmission loss (TL) of a material or building partition is a measure of its sound isolation ability.Recording the sound spectrum that passes through the material using a spectrum analyzer derives this rating. This rating is referred to as the Sound Transmission Class (STC) rating which is defined in ASTM Standard E413. When field measurements are used to derive this rating it is referred to as an FSTC.

Reverberation Time (RT60)
This quality is not only important in performing arts spaces, but in meeting rooms, gymnasiums, lobbies, and restaurants. Measurements include the use of a spectrum analyzer and for large spaces, a pink noise source driven over 100 decibels

Impact Insulation Class (IIC)
IIC is the measurement technique established for measuring the impact isolation of a floor assembly.  This procedure is similar to deriving an STC rating.  Procedures for deriving an IIC are established under ASTM designation: E1007. As a field test this procedure is referred to as an FIIC.