A central issue about which many people in the communities around the airport are concerned is the noise development in the region. Flight noise monitoring is aimed at continuously measuring the noise levels and exposures so that trends and changes can be identified. An important part of the monitoring is the Frankfurt flight noise index. The noise index reflects the noise load for a certain period, it is calculated once for the day (FTI = flight noise day index) and once for the night (FNI = flight noise night index).
A further aspect involves the monitoring of the measures for active noise abatement, protection. The effect of the measures depends, of course, on these new methods being applied as strictly as possible for take-offs and landings. The UNH monitoring, however, is not restricted to establishing compliance or deviations, but is also aimed at explaining how any such deviations have occurred.  
The documentation of current noise events is a special concern for many people living in the direct proximity of flight routes. For technical reasons, however, it can only take place with a certain time delay. The fact that such a “simple” demand actually involves an extremely complex procedure with many technical processes and mathematical calculations will be illustrated in the future information centre of the UNH using a sample measurement station as a practical example.
The communities also want noise calculations to be made on the basis of real flight events. The hope is that with the aid of this form of evaluation it will be possible to find out whether the actually flown routes deviate more frequently from the established and approved flight routes. Although such calculations based on the AzB08 are possible, the results have to be treated with great caution, as the necessary experience is not yet available. This is why a whole series of calculations and tests have to be carried out in the initial phase.  
The aim of flight noise monitoring is to ensure transparent information and representation. Monitoring provides access to independent and reliable information on flight noise, primarily for cities, communities and residents in the proximity of the airport, but also for other interested parties. All of the relevant information is published both on the website and in an illustrative, tangible fashion in the information centre.