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Appendix B

APPENDIX

 

 

 

 

B

Glossary of Terms

 

 

C-A

The C-A measurement is an SPL average that enhances the low- frequency components of the sound signal.

Figure B-1: C-A weighting response curve

Center frequency

The center frequency of each octave and third octave filter band.

CNEL

Community Noise Exposure Level. The accumulated exposure to sound measured in a 24- hour sampling interval and artificially boosted during certain hours. For CNEL, samples taken between 7 p.m. and 10 p.m. are boosted by 5 dB; samples taken between 10 p.m. and 7 a.m. are boosted by 10 dB. The values reported by SoundPro SE/DL ignore the threshold and use a 3 dB Exchange Rate, regardless how those parameters are set.

Criterion Level

Criterion Level. The average SPL that would result in 100% dose over the Criterion Time (usually 8 hours).

Models SE and DL

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3M SE, DL user manual Center frequency, Criterion Level, Appendix B