Page 9 - CertainTeed Ceilings E-Catalog

Environmental AcousticsTM design means feeling better, working better and healing better in any setting.
Our physical surroundings in any given setting contribute to a space’s acoustics. The environment can be made pleasant with wanted sounds, or it can be polluted by unnecessary and unpleasant noise. With proper Environmental AcousticsTM design, sounds can be controlled to ensure a space suits the way it is commonly used – whether that is concentration, collaboration or rest.
The graphics below explain the key factors that affect Environmental AcousticsTM design and how they are measured. The right blend of ceiling products can ensure these acoustical properties best accommodate a space’s intended usage.
Noise Reduction Coefficient (NRC), Ceiling Attenuation Class (CAC) and Articulation Class (AC) are measured according to the American Society for Testing and Materials (ASTM) standards.
Other factors that affect a room’s acoustics:
Sound Re ection
The reflection of sound can enhance the quality and volume of speech and music, as well as noise.
Noise Reduction Coef cient (NRC)
Noise reduction occurs when materials and objects convert sound into heat energy. Reflected sound always loses
some energy, but the amount greatly depends on the material of that surface. This is measured as the Noise Reduction Coefficient (NRC). An NRC of 0 indicates perfect reflection; an NRC of 1 indicates perfect absorption (measured according
to ASTM C423).
Articulation Class (AC)
This is a measure for rating the speech privacy performance of a ceiling system in an open plan environment where
the space is divided by half-height, cubicle-style walls. AC measures how much sound is re ected off the ceiling between the two divided, adjacent spaces.
<150 = Poor Performance >200 = High Performance (Measured according to ASTM E1111.)
Ceiling Attenuation Class (CAC)
The CAC is a measure
of how well a ceiling panel blocks sound transmission when traveling from one room into a ceiling plenum with no wall above and down into another room with the same type of ceiling (measured according to ASTM E1414).
Reverberation Time
After sound is ended at the source, it continues to re ect off surfaces until it is completely absorbed. This effect, termed reverberation, in uences speech intelligibility, enjoyment of music and noisiness of a room.
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ENVIRONMENTAL ACOUSTICSTM DESIGN