Mitigating Noise Pollution Level When Loading Useful Mineral …
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Table 2
Frequency noise centralizer
No. Noise level dB(A) LAeq Noise curves Cz Frequencies
16 Hz 31.5 Hz 63 Hz 125 Hz 250 Hz 500 Hz 1 kHz 2 kHz 4 kHz 8 kHz 16 kHz
1
72.0
68
64.92 76.6
89.2
81.14
70.01
69.68
67.04 64.43 58.09 49.03 42.81
2
92.7
91
66.12 73.37
75.64 78.08
80.64
84.57
86.92 87.88 84.18 77.03 64.68
3
66.3
62
62.17 72.6
74.06 67.57
64.45
62.72
61.24 59.12 55.13 50.68 43.46
4
69.4
66
67.56 69.18
68.35 65.68
64.73
64.83
65.85 62.88 53.44 44.19 28.32
5
64.2
61
65.24 61.95
65.07 63.25
59.47
59.5
60.28 57.61 52.06 42.95 29.63
6
78.0
75
69.39 71.42
70.99 71.05
70.30
70.93
71.9
72.45 69.97 65.96 52.72
7
90.8
87
66.95 75.8
82.85 86.62
87.00
89.56
86.00 83.23 78.66 70.98 59.44
8
86.6
83
73.46 87.7
81.83 83.75
84.1
82.49
80.68 80.5
76.86 64.8
52.3