Single and combined effects of air, road and rail traffic noise on sleep

Abstract

INTRODUCTION: It is a well known fact that noise annoyance depends on the traffic mode. Much less is known about differences in physiological effects, especially on combined effects. Therefore, the German Aerospace Center (DLR) investigated the effects of air (AI), road (RO) and rail (RA) traffic noise on sleep in the AIRORA study. METHODS: 72 subjects (40+/-13 years, 32 male) were polysomnographically investigated during 11 consecutive nights in the laboratory. Electrophysiological signals included EEG, EOG, EMG, EKG, respiratory movements and finger pulse amplitude. Cortisol and noradrenalin were measured in nocturnal urine samples. Each traffic mode consisted of five noise categories (maximum SPL 45, 50, 55, 60 and 65 dBA) with 8 different noise events, i.e. 40 noise events in total. Therefore, between 40 and 120 noise events were realistically played back during single (AI, RO, RA, RORO), double (AIRO, AIRA, RORA) and triple (AIRORA) exposure nights. The design was complemented with a noise-free control night and carefully balanced. RESULTS: Although annoyance due to aircraft noise was stronger compared to both rail and road traffic noise, preliminary analyses of parts of the physiological data do not support the same order. Final results will be shown and discussed on the conference.