Subjective effects of traffic noise exposure: reliability and seasonal effects

Abstract Repeated interview surveys were made in suburban residential areas of London. At six selected sites, four sets of interviews were conducted at different times of year and at a further two sites two sets of interviews were conducted during summer months. At all sites traffic noise levels were measured over 24 hours at each interview phase with a microphone 1 m from the dwelling facade at first floor level. Seasonal weather data were also collected. In the course of the repeated interviews the initial sample of 364 respondents was reduced to 222. The questionnaire included two types of noise nuisance scale, questions bearing on the typicality of road traffic conditions, and on the opening and closing of windows. The results confirm others already reported but in addition, show that if annoyance scores are averaged over repeated occasions a highly significant increase in reliability is obtained, and the proportion of score variance accounted for by noise increases significantly. No evidence was found of seasonal changes in traffic noise levels and annoyance scores did not vary significantly despite significant differences in the proportion of windows open at different times of the year.