Noise Criterion calculator

Sound Pressure Level (dB) - Octave band mid-frequency (Hz)

63 Hz (lim. 83 dB)
125 Hz (lim. 79 dB)
250 Hz (lim. 75 dB)
500 Hz (lim. 72 dB)
1000 Hz (lim. 71 dB)
2000 Hz (lim. 70 dB)
4000 Hz (lim. 69 dB)
8000 Hz (lim. 68 dB)

The calculator to calculate the NC - Noise Criterion.

Noise Criterion Octave Band Center Frequency (Hz)
63 125 250 500 1000 2000 4000 8000
Sound Pressure Levels (dB)
NC-15 47 36 29 22 17 14 12 11
NC-20 51 40 33 26 22 19 17 16
NC-25 54 44 37 31 27 24 22 21
NC-30 57 48 41 35 31 29 28 27
NC-35 60 52 45 40 36 34 33 32
NC-40 64 56 50 45 41 39 38 37
NC-45 67 60 54 49 46 44 43 42
NC-50 71 64 58 54 51 49 48 47
NC-55 74 67 62 58 56 54 53 52
NC-60 77 71 67 63 61 59 58 57
NC-65 80 75 71 68 66 64 63 62
NC-70 83 79 75 72 71 70 69 68
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