Methods for ensuring equity in noise-induced annoyance and sleep disturbance from different sources

Environmental noise impacts public health, with annoyance and sleep disturbance being among its most common effects. However, different noise sources are often assessed and regulated using heterogeneous criteria, which may lead to inequitable treatment. The national limits, the targets of World Health Organization or assessments are established exclusively on the basis of energy levels. Consequently, these values do not take into account the variability and differences in human perception of noise. This difference reflects into different slopes of the exposure-response functions for annoyance and sleep disturbance for different sources in the literature. The present study introduces analytical tools designed to ensure equity in the assessment of noise annoyance and sleep disturbance, regardless of the source. The proposed instruments are equalized Noise Source Predominance for an energy contribution analysis, and equalized Predominant Exposure histograms for population exposure analysis. These tools allow a comparative analysis of noise from different sources, taking into account health effects, in order to identify the point-to-point source with the greatest impact. The methods have been applied to five agglomerations as test-beds. The application demonstrated that, when disturbance adjustments are incorporated, the predominance of sources such as aircraft and railways becomes more evident, even in areas where traditional level-based assessments indicated other predominance. The proposed framework supports a more equitable basis for exposure assessment and prioritization of mitigation measures. As such, it provides a valuable decision-support tool for acousticians, urban planners, and policymakers seeking to align noise management strategies with health-relevant criteria.