Relationships between environmental noise and social–economic factors: Case studies based on NHS hospitals in Greater London

Sound environment is an important part of the overall environmental sustainability. For example, the windows of buildings in noisy environments often need to be sealed, which would discourage low energy strategies based on natural ventilation. The aim of this study is to investigate the relationships between environmental noise levels, especially in hospitals, and selected social–economic factors; as well as to determine how noisy the NHS (National Health Service) hospitals in Greater London are. Calculated noise maps are used through a series of data processing, and 28 social and economic factors are considered. As expected, the NHS hospitals in Inner London are considerably noisier than those in Outer London, by 5.4dBA in average. It is shown that the environmental noise levels of NHS hospitals in Greater London have close relationships with a number of social–economic factors. Generally speaking, with a higher noise level in an area, the household size is smaller and there are more one-person households. Detached, semi-detached and terraced houses are more likely located in relatively quieter areas, while flats are more likely to be found in noisier areas. This is also associated with the unemployment rate, which tends to be higher in noisier areas. The pupil/teacher ratio has a significant negative correlation with noise levels. It is interesting to note that although the population factors, including population density, total fertility rate and crude death rate, have significant correlations with the environmental noise levels, correlations between noise levels and residents' health conditions are rather low.