Influence of naturalistic traffic noise in the free field

The direct effects of sound energy on human hearing are well established and accepted but previous research about the effects of noise exposure on medical parameters has been carried out mainly under laboratory conditions. Such test arrangements are not representative of the real impacts on humans, especially at night during sleep phases. The two main objectives of this proposal are to investigate the influence of road and rail traffic noise on human sleep patterns and additionally to explore the relationship of subjective perception of test subjects with objective measured psychoacoustic and physiological parameters. The crucial point of the proposal is that all measurements will be done in the free field with real-life situations. Based on past experiences of the Graz University of Technology with acoustical measurement techniques in free field areas a standardized method for objective acoustical measurements in residential environments of test subjects will be developed. The goal of acoustical measurements is to achieve a time-synchronicity between the results of the electronic questionnaire (traffic noise annoyance-rating, experiences, feelings and behaviour) and acoustical parameters including sound pressure level and psychoacoustics reflecting the total quantity and quality of the test subject`s acoustic exposure.

Classic research about the effects of noise exposure on non-auditory health effects has been carried out with established sound indicators like Lden or Lnight using the A-weighting. The relation between psychoacoustic indicators and objective health parameters is less well investigated also in soundscape studies. Studies on the direct effects of sound energy on human hearing, on the other hand, are well established and accepted, but previous research about the effects of noise exposure on medical parameters has been carried out mainly under laboratory conditions. Such test arrangements are not representative of the real impacts on humans, especially at night during sleep phases. The two main objectives of the project INTRANOISE therefore, were to study the effect of road and rail traffic sound on human sleep patterns and explore the relationship between the subjective perceptions of 100 test persons and objectively measured psychoacoustic and physiological parameters. The crucial point is, that all measurements were done in the free field during real-life situations, at the home of interested test subjects. Based on past experiences of the Graz University of Technology with acoustical measurement techniques in free field areas a standardized method for objective acoustic measurements in residential environments of test persons was developed. The goal of acoustical measurements is to achieve a time-synchronicity between the results of a questionnaire (traffic noise annoyance-rating, experiences, feelings and behavior) and acoustical parameters including sound pressure level and psychoacoustics reflecting the total quantity and quality of the test subjects acoustic exposure. Results of the study show significant correlations between the subjective noise annoyance of the test subjects, the measured sleep quality and psycho-sociological indicators.