What does NRC measure in interior acoustics?

What does NRC measure in interior acoustics?

• A. Noise Reduction Coefficient; the average sound absorption coefficient of a material.
• B. Noise Reduction Constant; the amount of noise a surface reflects.
• C. Noise Reduction Index; the decibel reduction of sound.
• D. Neutral Reverberation Coefficient; the reverberation time in a room.

Answer: (A)

NRC represents how much sound energy a material absorbs across common room frequencies. It’s the average of the absorption coefficients at 250, 500, 1000, and 2000 Hz, giving a single value from 0 to 1. Higher numbers mean more absorption and less sound reflected back into the room, which helps reduce overall reverberation. It’s a property of the material tested in a standard setup (usually in a reverberation chamber) and is not a measure of how much a surface reflects, a direct decibel reduction, or reverberation time itself.

NRC represents how much sound energy a material absorbs across common room frequencies. It’s the average of the absorption coefficients at 250, 500, 1000, and 2000 Hz, giving a single value from 0 to 1. Higher numbers mean more absorption and less sound reflected back into the room, which helps reduce overall reverberation. It’s a property of the material tested in a standard setup (usually in a reverberation chamber) and is not a measure of how much a surface reflects, a direct decibel reduction, or reverberation time itself.