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INSULTECH |
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About Industrial Noise Many years ago, a noisy workplace meant a productive workplace. Industrial workers assumed that the noise levels were just part of their jobs. In 1970, the Occupational Safety and Health Act (OSHA) set time duration limits for employees exposed to increased noise levels. These limits are shown below: |
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Sound Pressure Level (dBA) |
83 |
85 |
87 |
90 |
92 |
95 |
97 |
100 |
102 |
105 |
108 |
110 |
|
Reference duration (hours) |
21.1 |
16 |
12.1 |
8 |
6.1 |
4 |
3 |
2 |
1.5 |
1 |
.66 |
.5 |
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Source: OSHA Appendix A - Section 1910.95 Noise Exposure Computation To allow comparison of different sound levels, some common noise sources and their respective sound pressure levels, in dBA and N/m2, are listed below: |
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SPL (dBA) |
Source |
Sound Pressure (N/m2) |
|
0 |
Absolute threshold of hearing |
0.00002 |
|
15 |
Normal threshold of hearing |
0.00011 |
|
30 |
Whisper at 3' |
0.0006 |
|
45 |
Quiet park |
0.0036 |
|
60 |
Normal conversation at 3' |
0.02 |
|
75 |
Noisy office |
0.11 |
|
80 |
Vacuum cleaner |
0.20 |
|
85 |
Electric blender |
0.36 |
|
90 |
Noisy factory |
0.63 |
|
95 |
Dog bark at 3' |
1.1 |
|
100 |
Car horn at 3' |
2.0 |
|
105 |
Jackhammer |
3.6 |
|
110 |
Loud rock band |
6.3 |
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