Noise indices for aircraft noise event assessment analysis with their dependence from measurement issues and impact assessment

Abstract

In Poland equivalent sound levels LAeq, DAY and LAeq, NIGHT are used for noise control around the airports [1, 2]. Both of them are quite efficient for the airports with >10 000 flights annually, but for not so active airports their use to control the acoustic climate is questionable. Very often the maximum sound levels LAmax is used for such purposes, but few questions exists concerning the measurement issues and impact assessment. However, a clear definition of this indicator is difficult. The use of each type of indicator (LAmax SLOW, LAmax FAST, LAmax IMPULS, LAeq max 1s) has different consequences. Commonly used is the value of LAmax FAST. However, the most formal indicator LAmax SLOW. During the measurements the options “Fast” or “Slow” may provide the difference between measured results up to 7 dBA. The usage for monitoring purposes is possible due to some effective possibilities for the source identification and more accurate time fix of the noise event. But for impact analysis the metric LAmax is quite poor, there are many other metrics are looking more effective than LAmax. SEL is also useful metric, which is recommended somewhere to be used for noise event analysis and assessment. Where the continuous monitoring stations air noise is only possible to use LAeq max 1s.Based on analysis of aircraft noise measurement results of many authors present ways of converting. [...]