Noise Criteria Curves: NC
Noise Criteria (NC) and Room Criteria (RC) curves for HVAC acoustics design. NC curves per ANSI S12.2-2008 from NC-15 through NC-70 (12 curves), and RC Mark II curves per ASHRAE from RC-25 through RC-50 (6 curves). Each curve has 8 octave band center frequencies (63-8000 Hz) with maximum allowable sound pressure levels in dB. Includes recommended occupancy type and equivalent dBA background noise level. 144 records total.
| criterion type | curve point | background noise dBA equivalent (dBA) | max sound pressure level dB (dB) | notes | octave band center Hz (Hz) | rating | recommended occupancy |
|---|---|---|---|---|---|---|---|
| NC | NC-15#1000 | 25 | 17 | NC-15 at 1000 Hz octave band | 1,000 | NC-15 | concert_hall |
| NC | NC-15#125 | 25 | 36 | NC-15 at 125 Hz octave band | 125 | NC-15 | concert_hall |
| NC | NC-15#2000 | 25 | 14 | NC-15 at 2000 Hz octave band | 2,000 | NC-15 | concert_hall |
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