Zfi, an Index for the Effects of Aircraft Noise on the Population: Experiences

Noise effect indexes have recently become a popular concept to estimate the impact of aircraft noise on people. Such indexes describe the integral effect(s) of aircraft noise (annoyance and/or sleep disturbance) on the population in the vicinity of airports. In this paper, we report on the Zurich Aircraft Noise Index (ZFI) which became operational as an effect-oriented monitoring tool serving noise abatement policy in the year 2007. We present the concept and implementation of the ZFI, as well as results and insights obtained so far. The potential and limitations of the index to express the number of affected persons, its sensitivity to changes in population figures and air traffic as well as the possibilities to separate different influencing factors are discussed. The results may serve as a basis to further improve noise effect indexes in the future.