Contribution
Influence of a measurement threshold level on the calculation of aircraft sound exposure levels
* Presenting author
Abstract:
A measurement threshold is used to ensure that an aircraft noise event is clearly distinguishable from the ambient sound in automatic aircraft noise monitoring devices. Any noise below the measurement threshold level is not considered when evaluating aircraft noise events. As a consequence, the edges of a level-time curve are also being cut off, which thus leads to a different sound exposure level compared to the actual value. The lesser the maximum level exceeds the measurement threshold level, the greater is this difference. This difference can be particularly relevant for low noise levels or large distances from the airport. In this study, the influence of a measurement threshold level on the calculation of sound exposure levels is analyzed theoretically with calculated noise levels. The study also includes the analyses of level frequency distributions (resulting from multiple flyovers), which are truncated at lower levels due to the measurement threshold.