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