title: Quantification of the exposure and effects of road traffic noise in a dense Asian city: a comparison with western cities.
abstract: BACKGROUND
  Particularly in Asia, dense, traffic-intense, and usually high-rise cities are increasingly the norm. Is existing knowledge on exposure to road traffic noise, and on people's response to such exposure, garnered primarily from western cities, equally applicable in these?
  
  
  METHODS
  Hong Kong has high population and traffic density and a high-rise building form. Road traffic noise exposure was estimated, and residents' responses to traffic noise measured, for a sample of 10,077 dwellings. Noise level estimates were based on three-dimensional modelling. Best international survey practice measured self-reported annoyance and sleep-disturbance. Benchmark estimates of exposure, and of annoyance and self-reported sleep disturbance, are provided. We compare Hong Kong exposure with those of European cities, and the exposure-response relationship for annoyance in Hong Kong to those reported from elsewhere - based on the tolerance limits of previous syntheses. Exposure-response for self-reported sleep disturbance is also compared.
  
  
  RESULTS
  The distribution of exposures of dwellings in high-rise, high-density, Hong Kong is different from those reported from Europe, but not at the higher noise levels. The exposure-annoyance relationship for road traffic noise was from the same population of exposure-response relationships, being well within the tolerance limits, of studies used to generate the synthesized Miedema and Oudshoorn curves. The exposure-response curve for self-reported sleep disturbance was parallel to that of Miedema and Vos but slightly lower.
  
  
  CONCLUSIONS
  The proportion of the Hong Kong population exposed to high levels (>70 dB) is similar to that found in Europe. However, a much higher proportion, compared to European cities, is exposed to Lden levels of 60-64 dB, and a much lower proportion to lower levels (<55 dB). There is no evidence that the exposure-response relationships for annoyance and self-reported sleep disturbance in Hong Kong are different from relationships synthesized from earlier studies - despite the western bias and temperate-climate bias in the studies available in the syntheses. This is an important finding for urban planning and traffic noise management of the growing mega-cities in the world whose built forms can be expected to reflect that of Hong Kong more than of cities in the west.
authors.affiliation: Urban Research Program, Griffith School of Environment, Griffith University, Nathan, Brisbane, Australia. Lex.Brown@griffith.edu.au.
authors.forename: Alan Lex
authors.initials: AL
authors.lastname: Brown
authors.affiliation: Department of Geography and Resource Management, The Chinese University of Hong Kong, Hong Kong, China. kinchelam@cuhk.edu.hk.
authors.forename: Kin Che
authors.initials: KC
authors.lastname: Lam
authors.affiliation: National Institute for Public Health and the Environment, Centre for Sustainability, Environment and Health, Bilthoven, The Netherlands. irene.van.kamp@rivm.nl.
authors.forename: Irene
authors.initials: I
authors.lastname: van Kamp
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004781:Environmental Exposure; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009624:Noise, Transportation / Q000009:adverse effects*; D011156:Population Density; D057566:Self Report; D012893:Sleep Wake Disorders / Q000453:epidemiology* / Q000209:etiology; D055815:Young Adult