Gjestland is a Senior Research Scientist Emeritus at SINTEF, Norway. He has more than 50 years’ experience in noise research in particular noise annoyance and people’s reactions to noise. Gjestland is a member of the International Commission on Biological Effects of Noise. He has chaired its Community response to noise team and is currently chair of its Noise policy team. Gjestland has participated in several EU-funded projects on environmental noise and he is a member of EU’s Noise Expert Group. He has also served as temporary advisor to World Health Organization, ICAO, EASA and FAA. Recently Gjestland has published several papers with critical remarks to the new recommendations from WHO regarding annoyance from transportation noise. Gjestland is a Fellow of the Acoustical Society of America and honorary member of The Acoustical Society of Norway and The East-European Acoustics Association.
Fifty years of aircraft noise – still looking for the right dose-response function
For more than fifty years researchers have tried to establish predictively useful relationships between aircraft noise exposure and annoyance. Several dose-response functions have been developed, and quite recently the World Health Organization presented a new curve that dramatically increases the predicted prevalence of annoyance with the noise exposure. According to the WHO recommendation the noise level must be kept below Lden 45 dB in order to avoid adverse health effects.
A systematic re-analysis of social surveys conducted over the past half century shows that the annoyance response has been remarkably stable. Under equal conditions people today are annoyed to the same degree as they were 25 or 50 years ago. Recent claims that the annoyance has increased have been based on faulty assumptions and a missing understanding of the importance of the effects of non-acoustic factors.