Abstract
The relationship between the prevalence of noise induced annoyance and the noise exposure is traditionally described by a cumulative noise metric such as DNL. Such dose-response functions have no restrictions regarding how the dose has been derived, e.g. either a large number of low level noise events or a small series of high level events. Community Tolerance Level values (CTL) for 32 aircraft noise surveys have been examined with respect to the yearly number of aircraft movements. The airports included in this study were divided into two categories: "high-rate-of-change" (HRC) airports and "low-rate-of-change" (LRC) airports. HRC airports experienced large changes in their operational patterns within three years prior to the surveys, or there had been announcements of controversial plans for major changes, and/or extensive public discussions and media focus on operational issues. LRC airports experienced only minor changes in operations and noise-related controversies. At LRC airports there is a clear relationship between annoyance and the number of aircraft movements. At equal DNL the prevalence of annoyance increases with an increasing number of movements. At HRC airports the prevalence of annoyance is higher. However, the same dependency on number of aircraft movements cannot be found.