NORAH (Noise Related Annoyance, Cognition, and Health): Questions, designs, and main results

The German multidisciplinary research project NORAH (Noise Related Annoyance, Cognition and Health) was aimed at providing a broad and scientifically reliable description of the effects of air, road and rail traffic noise on the health and life quality of residents in the vicinity of airports. Ten scientific institutes participated and performed surveys, secondary health data analyses, sleep quality registrations, blood pressure registrations, and special tests on children at school. Main results: 1. At all four airports studied, the percentage of persons highly annoyed by air traffic noise at comparable noise levels was larger than would be expected from the so-called "EU standard curves" [1]. 2. With respect to cardiovascular health risks, the effects of rail and road traffic noise on heart failure, myocardial infarction, and stroke were more clearly seen as compared to the effects of aviation noise. 3. There was no statistically significant increase of self-registered blood pressure values with increasing LpAeq for the evening and night-time for transportation noise. 4. Night-time sleep of residents showed a diminished number of aircraft associated awakenings with the introduction of the night curfew at Frankfurt Airport for a group being in bed during 22:00-22:30 hrs until 06:00-06:30 hrs. The probability of awakening due to a single aircraft event, however, did not change before and after the night curfew. 5. Multilevel analyses revealed a significant linear association between aircraft noise levels at school and decreasing reading performance in second graders. A one month delay in reading was observed for an increase in noise levels by 10 dB LpAeq.