Acoustic basics

The aircraft noise data of the NORAH Study have been calculated based on radar recordings of the German flight safety authority. By comparison to noise levels measured on site, the acousticians were able to document that the calculated levels map the actual exposure very well.

The NORAH acoustic database contains about 30 “acoustic characteristics” for every study participant, among others long-term energy equivalent noise level for day (6 a.m. – 10 p.m.) and night (10 p.m. – 06 a.m.), average maximum levels and maximum level statistics, each separated by aircraft, road and rail traffic noise, for the respective year before the examination and for the participants of the study on health risks even for the years 1996 to 2014. Of course, all data are anonymised according to the provisions of data privacy.

The data on road traffic noise are based on traffic counts of the state and the municipalities. Rail traffic noise data come from the Federal railway office and the Bahnumweltzentrum Berlin. Digital terrain models are used by NORAH to also consider obstacles in sound propagation – e.g. when a train line is behind a hill or building rows deflect noise.

The NORAH acousticians also considered information from the study participants on the floor or position of their bedroom in the deeper survey on the health situation. These factors may considerably influence how much noise actually reaches the study participant’s ear.