ATT Zirocco-M50, Руководство по эксплуатации

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TWA exposiure Operator
Working hours 1 2 3 4
Work exposure dB(A) 103 103 103 103
(100% Machine performance level)
TWA dose dB(A) 89 93 96 98
NRR protection rating 15 23 29 33
dBA reduction (NRR-7)/2 4 8 11 13
Requirement dB(A) 85 85 85 85
In this table the LWA value is used in the calculation of the TWA dose as a “worst case”, although the
operator normally would operate the machine at lower performance level because the marking equipment
often is limiting the overall operation.
The highest NRR rating for earplugs is 33, and the highest available NRR rating for earmuffs is 31. These
values reflect the level of noise protection available for each device when worn alone. Combining earplugs
with earmuffs can offer a NRR protection level of 36.
The environmental exposure will depend on how the work is done. It is possible to work below an
environmental sound pressure LWA of 96, if that is needed, but it will require that the machine is operated
below 50% of the maximum possible.