The aim of this study was to evaluate subjective noise perception and objective parameters of circulation in the vicinity of the Frankfurt airport. Two areas were selected in which aircraft noise was the predominant source of noise (and was) created by planes induced by take off but not during landing. Data of residents living in the two areas were observed over a period of twelve weeks, one area being exposed to air traffic noise for three quarters of the given time, the other for one quarter of the time.
Methods: Fifty three volunteers (age 50-52 +/- 15 y) monitored their blood pressure and heart rate over a period of three months by using an automatic device with digitized readings. They also protocolled their own subjective perception of noise and sleep quality. Thirty one probands were living West of the airport (West group) and were exposed to a nocturnal equivalent continuous air traffic noise level of L(eq(3)) = 50 dB(A) outside, during flight direction 25 to the West. Twenty two probands were living East of the airport (East group) and were exposed to L(eq(3)) = 50 dB (A) during flight direction 07 to the East. During the opposite flight directions air craft noise corresponded to L(eq(3)) = 40 dB(A) in both areas. Frankfurt airport operates direction 25 for about 75% of the time on average and direction 07 for 25% of the time.
Results: The average blood pressure was significantly higher in the West group with higher noise exposure. Morning systolic blood pressure was 10 mmHg and diastolic pressure 8 mmHg higher in the West group. Throughout the observation period, the East group showed a parallel between daily changes in noise and subjective noise perception. In the West group such a parallel did not appear. This reaction was considered to be the consequence of the high noise exposure of the West group.
Conclusions: It is concluded that a population exposed to a nocturnal equivalent continuous air traffic noise level of L(eq(3)) = 50 dB(A) for three quarters of a given time has a higher average blood pressure compared to a population exposed to the same equal energy noise level for only one quarter of the time. Within the East group a parallel between noise exposure and noise perception was observed, while in the West group this parallel did not appear. The difference is considered to be the consequence of higher noise stress levels in the West group. The data are in accordance with recent epidemiological studies and indicate that a nocturnal aircraft noise of L(eq(3)) = 50 dB(A) can have negative effects on subjective noise perception and on objective parameters of circulation.