Heard but not seen: a narrative review of traffic noise impacts and the amenity cost awarded to pedestrians

• Provides a transdisciplinary review of traffic-induced noise impacts on pedestrians. • Distinguishes noise from sound to emphasise perception, context, and lived experience. • Synthesises objective, psychoacoustic, soundscape, and modelling approaches relevant to pedestrian-scale assessment. • Demonstrates how traffic noise shapes health, behaviour, accessibility, and urban equity. • Repositions noise assessment toward receiver-centred, walk-quality and supports planning and policy integration. Traffic-Induced Noise Pollution (TINP) is increasingly recognised as a major impediment to pedestrian comfort, accessibility, and health in urban environments around the world, making it both a societal and global problem. While sound can be measured objectively, noise is inherently subjective and context-dependent, making it difficult to characterise and regulate using traditional acoustic indicators alone. This narrative review synthesises multidisciplinary knowledge on how TINP influences pedestrian experience, behaviour, and wellbeing, and evaluates the strengths and limitations of historical and contemporary noise measurement and assessment methods. By integrating evidence from acoustics, psychology, health, transport studies, and urban design, the review demonstrates the need for combined objective and subjective approaches to better represent the lived pedestrian experience and monitor the quality of the pedestrian environment. Key contributions include highlighting gaps in current assessment frameworks, identifying emerging approaches suited to pedestrian-centred evaluation such as psychoacoustic and soundscape-based methods, and outlining implications for research and practice. The findings support the development of multisensory planning and policy frameworks that promote active transport, enhance environmental equity, and move beyond the conventional focus on traffic-noise emissions. Taken together, these insights provide a foundation for developing pedestrian-centred tools that can help cities design, evaluate, and manage walkable environments exposed to TINP.