Public tolerance to aircraft noise has decreased, reports new UK study
Jim Fitzpatrick, Aviation Minister
Fri 2 Nov 2007 – An independent study of public attitudes to aircraft noise was published today by the UK’s Department for Transport (DfT). Conducted by consultants MVA, The Attitudes to Noise from Aviation Sources in England (ANASE) study revealed two key conclusions.
Firstly, the public is more annoyed by all levels of aircraft noise than was the case in 1985, when the last major study in this field was carried out. Secondly, there is no identifiable threshold at which noise becomes a serious problem. Even relatively low levels of noise can cause some annoyance, which rises as the noise increases.
Responding, Aviation Minister Jim Fitzpatrick said: “The Government accepts that noise from aircraft is a growing concern and will take into account those people affected by aircraft noise when considering the costs and benefits of future projects.
“The study also makes clear that it is impossible to identify any particular level at which noise becomes a serious problem.
“One interpretation of this is that Government could abandon the existing restriction on noise levels at Heathrow Airport of 57 decibels and above. But we believe it is right that we retain this as a safeguard for those who are most affected by aircraft noise. We have already said that any expansion of Heathrow must not increase the area where people experience the highest noise levels and this will be fully considered in the forthcoming Heathrow consultation.”
The consultation over a future third runway at Heathrow is due to be launched by the DfT before the end of the year and the study’s findings are sure to be a factor in the proceedings.
The DfT appeared equivocal in its backing for the study, pointing out that the peer group reviewing it “did not feel that the valuations produced by the study were conclusive, and specifically counselled against using the detailed results in the development of Government policy.”
The peer group consisted of Peter Havelock, Head of Environmental Research and Consultancy, Directorate of Airspace Policy, Civil Aviation Authority, and Stephen Turner, Director of Acoustics, Bureau Veritas. In their review of ANASE, they expressed concern about the overall robustness of the ANASE study, citing “technical and methodological uncertainties” and suggested that the DfT should “clarify what reliance, in their view, should be placed on the ANASE finding by planning authorities, regulators, practitioners and other interested parties. Without such guidance, there is a strong risk that there will be many different and conflicting interpretations of the information contained within the ANASE reports.”
The study found that although noise levels of modern aircraft were lower, “the contribution of aircraft numbers to annoyance has increased quite markedly”. However, it says more research is needed to explore how accurately people associate a reduction in aircraft numbers with a change in overall sound levels. “It may be that respondents perceive that a reduction of a few jumbos during a particular period of the day would have considerable impact on their overall sound levels yet in reality might not even notice the reduction in practice.”
As a result of its findings, the study also queried whether LAeq, the metric used in measuring the relationship between aircraft noise and community annoyance, should be reviewed. “Because of its instability over time, use of the LAeq measure to predict future levels of annoyance may be misleading.”
Following the 1985 study, the Aircraft Noise Index Study (ANIS), LAeq was adopted by the Government as the measurement of noise exposure at the three major London airports – Heathrow, Gatwick and Stansted – with other major UK airports soon following suit. Based on the ANIS study, the Government decided that 57dB(A) LAeq,16h marks the approximate onset of significant community annoyance from aircraft noise.
The study found support from campaign groups such as HACAN ClearSkies, which is fighting against any expansion at Heathrow. The group accused the DfT of “sneaking out” the ANASE study which, it says, suggests that significant annoyance starts at 50dB(A) rather than at 57dB(A). “This means that many more people than previously admitted are affected by aircraft noise. At Heathrow there are 258,000 residents inside the 57-decibel area, but over 2 million live inside the 50-decibel area.”
John Stewart, Chair of HACAN, said: “Local people have been vindicated. For over 10 years now local people in areas more than 15 miles from the airport have been complaining about aircraft noise problems. This study shows they have not been imagining it.”
The study is published on the same day British Airways’ Chief Executive Willie Walsh called for increased runway capacity to create more take-off and landing slots and enable Heathrow to compete with other European hubs like Paris, Amsterdam and Frankfurt (see separate news article).