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In a field study, carried out between 1994 and 1998, the noise impact as well as psychological reactions by questionnaire were measured for 1600 persons in 4 areas exposed either to railway or to road traffic noise. Furthermore body movements during sleep were assessed for 377 persons by actimeters. The noise impact was obtained by noise calculations and, for the sample of the 377 sleep subjects, by measurements inside and outside the bedrooms. The acoustical analyses show typical differences between road and rail traffic noise.

An interdisciplinary field study examining the annoyance by rail and road traffic noise with special regard to sleep disturbance was carried out. The noise induced responses were determined by questionnaires and physiological measurement of sleep disturbance. For subjects taking part in the physiological examination, acoustical measurements have been taken inside and outside the bedroom. The individual noise levels for all subjects have been calculated using the German standards RLS90 and Schall03. As input variables (such as number and speed of passing trains or vehicles) for these calculations on one hand measured data and on the other hand official data have been used. Whereas the measured data deliver reliable information about the traffic during the physiological measurements, the official data mostly refer to maximum (e.g., speed) or average values. Furthermore, the noise levels have been calculated for different measurement points. Thus, together with the measured noise levels a variety of subject individual level values have been collected. The selection of these noise levels and the effect on the noise response relationship shall be discussed. Special regard will be taken on indoor and outdoor levels and the aspects of measurement and calculation and its input data.

Somewhat similar to the acoustic problems that were uncovered with the replacement of combustion engines with electric motors in cars, the retrofitting of all DB Cargo freight wagons with low-noise brakes caused other disturbing noise emissions to become more prominent. Among these, the periodic beating sounds originating from flattened wheel treads attract most attention. As there is no sufficiently validated solution for wayside wheel flat detection which meets the requirements of precise detection, focus on acoustic relevance and economic feasibility, the German Federal Environmental Agency has initiated a research project to determine an acoustic maintenance criterion for flat spots. In this contribution, we present the results of psychoacoustic analyses performed on a dataset comprising audio recordings of 200 cargo train passings. Regions with perceptible flat spots are labelled by trained ears. Common acoustic and psychoacoustic quantities are calculated for signal windows of classes "flat spot" and "no flat spot" and statistical analyses are performed to find quantities which qualify best for a separation of both classes. The effects of window size and sample rate are examined. Based on the results of listening tests, an acoustic classification criterion for the annoyance of wheel flats is proposed.