New insights into perception of aircraft and community noise events

The current practice of basing all noise monitoring on A-weighted day/night levels has often been criticised. Questions as to what is really happening in the "noisescape" have been raised, with consequences for managing complaints and future planning. At the same time, some permanent noise monitoring terminals are now available to record simultaneously A-weighted, C-weighted, Z-weighted, stationary loudness, non-stationary loudness, and effective perceived noise levels of noise events. These data, together with other available functions in permanent monitors such as dominant pitch, frequency percentile measures and neural network source characterisation, provide useful resolutions of the more complex events that are not purely due to aircraft. The collection of two years of continuous records of all of these parameters with audio, from a modified permanent airport noise monitor, that is exposed to a variety of community, traffic and aircraft sounds, provides a valuable data set for further study. In particular, event-threshold parameters, maximum levels and exposure levels based on the perception metrics, in comparison with the common A-weighted metrics, have been obtained. Together with recordings from some other sites, new insights into what is really happening in noise events are presented.