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Noisy workshops should be concentrated in the hinterland, far from other
manufactures, and protected by area of tree and shrub plantings.
Individual protection means:
a) antiphons as headphones and liners, mixtures of fibers of organic cotton and

germicidal ultra-thin polymer fibers (reduce noise by 15–30 dB);
b) helmets – under the influence of the noise levels > 120 dB.
The maximum allowable noise level in the workplace (Table 10.3, Table
10.4).
Table 10.3 - The maximum allowable of the sound pressure level for certain
workplaces is defined by DSN 3.3.6.037-99
Workplace Sound pressure level dB, in the octave bars with the The
geometric center frequencies, Hz sound
63 125 250 500 100 200 4000 800 level,
0 0 0 dBA
Rooms for 71 61 54 49 45 42 40 388 50
programmers
Rooms for 79 70 68 58 55 52 50 49 60
management,
working
environment
Fixed workplaces in 95 87 82 78 75 73 71 69 80
the production
rooms

Table 10.4 - Eight-hour average sound pressure level above which risk for
hearing loss exists (Occupational Safety and Health Administration (OSHA),1971–Present)
Exposure Time, Hrs Permissible Exposure Limit (PEL), dBA

No time limit <90
89 0
49 5
2 100
1 105
0.5 110

Revision Questions

1) Basic parameters of the noise.
2) Effects of noise on the human body.
3) Protective measures against noise

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