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Data Addendum
Peak C Level Range
The nominal peak C level range is 55 dB to143 dB.
Effects of background noise (sections: 5.6.4, 5.6.5, 9.2.5d)
Background noise can cause considerable error in measurement when its intensity is close to that of a particular sound source of interest. When it is not possible to eliminate or reduce the background noise, use the curve shown in Figure 4 to correct for the effect of the background noise on the measurement. For example, if the background noise is 45 dB and the sound of interest measures 51 dB, the difference between measurement and background noise is 6 dB. From Figure 4, for a 6 dB difference, 1.3 dB should be subtracted from the measurement. The correct measurement is therefore 51 dB- 1.3 dB= 49.7 dB.
Correction in dB
Sound Examiner
