Svantek SV 971A, Руководство пользователя

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SV 971A User Manual
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PTP PTC result expressed in percent. Appendix D
TWA Time Weighted Average - average A-weighted
sound level for a nominal 8-hour workday with Time
Weighting S and Exchange Rate 5. TWA is usually
measured with A-weighting and Slow response
detector type. TWA is calculated from the measured
LAV (taking Threshold Level into account) and a
Reference time of 8 h. Mainly used in the USA for
assessing the noise exposure for a worker during a
workday. Appendix D
ULT Upper Limit Time - time that SPL exceeded the
“ULT Threshold Level” set during configuration. Appendix D
PrTWA Projected Time Weighted Average is calculated
from the measured LAV (taking THRESHOLD
LEVEL into account) and the exposure time. Appendix D
Lc-a Leq that enhances the low-frequency components
of the sound signal. It is the result of subtracting an
A-weighted LAeq from a simultaneously collected
C-weighted Leq.
Appendix D
EX Expected value. Calculated on the basis of 100ms
Leq results.
Appendix D
SD Standard deviation. Calculated on the basis of
100ms Leq results.
Appendix D