NRC (Noise Reduction Coefficient) is a standard measurement for a material’s acoustical absorption ranging from 0.00 (no absorption) to 1.00 (total absorption).

CAC (Ceiling Attenuation Class) is a standard measurement of a ceiling system’s ability to block sound between two closed spaces. CAC values of 35 or greater are recommended to achieve speech privacy.

NIC (Noise Isolation Class) is a standard measurement of total sound attenuation between two closed spaces. It considers the ceiling, wall, and other interior finishes.

AC (Articulation Class) is a standard measurement of a ceiling system’s ability to attenuate sound within a large open plan space. AC values of 170 or more are recommended to reduce speech distraction.

Sabin is the unit of measure for total sound absorption of an acoustical object (like blades, baffles, clouds, and canopies).