Glossary


Sound Absorption Coefficient

Sound absorption coefficient describes the ability of a material to absorb sound, expressed as a fraction of incident sound. The sound absorption coefficient is frequency-specific and ranges from 0.00 to 1.00. For example, a material may have an absorption coefficient of 0.50 at 250 Hz, and 0.80 at 1,000 Hz. This indicates that the material absorbs 50% of incident sound at 250 Hz, and 80% of incident sound at 1,000 Hz. The arithmetic average of absorption coefficients at midfrequencies is the noise reduction coefficient.