Soundscape assessment in a hostile urban environment: a case study of Vale do Anhangabaú

Urban noise pollution significantly impacts public health. To address this issue, the soundscape approach, which considers both objective acoustic data and subjective perceptions from volunteers' participation, can be effective. In Brazil, research on this topic has been expanding; however, further data collection and field studies are essential to capturing the complexities of local and cultural contexts. This research examines the soundscape evaluation process at Vale do Anhangabaú, a historically and socially significant public square in São Paulo, Brazil's largest city, with over 11 million citizens. The methodology followed ISO 12913 and ABNT NBR 10151 standards, including in situ acoustic measurements, soundwalk, and questionnaires. The study site, under private management, is located in a downtown area where socio-economic disparities are more pronounced, often contributing to a perceived sense of insecurity. In addition, during fieldwork, security guards interrupted the soundwalk with a hostile approach, significantly influencing the group's overall perceptions. Consequently, data analysis focused on the extent to which this external event overshadowed participants' evaluations of the soundscape itself. Findings suggest that the security personnel's interference negatively impacted the questionnaire responses, highlighting how non-acoustic factors can shape urban soundscape perceptions.