New Practice for Standard Practices for Acoustical Material Testing Specimen Preparation
1. Scope
1.1 Test specimen preparation has a significant effect on the outcome of several acoustical material test methods, including C384, C522, E1050, and E2611. The mounting conditions of the test specimen for these test methods require that a seal be created when the material is mounted into the test apparatus. The data accuracy and repeatability for these test methods may be affected if the test specimen is not prepared to fit within the tolerances of the small material test systems associated with this guide. If the specimens are not prepared adequately, the sides of the specimen will interact with the sidewalls of the test apparatus creating boundary conditions that may significantly affect the outcome of the measurement. This guide is for preparation of acoustical materials test specimen for measurement with the aforementioned standard test methods.
Keywords
absorption; acoustical materials; airflow resistance; band saw; cutting die; impedance tube; lathe; normal incidence; transmission loss; water cutting machine
Rationale
Standard practices for test specimen preparation for acoustical material testing should improve within- and between-laboratory precision for several existing Test Methods, including C384, C522, E1050, and E2611 by providing the user of these Test Methods with a more uniform and repeatable approach to preparing small disc-shaped test specimens.
