Effects of low-level electric vehicle noise on attention, electrodermal activity, workload, and annoyance

With the rise of electromobility, electric vehicles (EVs) and their acoustic vehicle alerting systems (AVAS) are becoming a part of urban acoustic environments. While AVAS signals are designed to enhance traffic safety, their environmental noise impact on non-involved listeners has yet to be systematically studied. This study investigates the effects of low-level indoor EV noise, including three common AVAS types, on attention, electrodermal activity (EDA), perceived workload, and noise annoyance. Sixty participants completed a combined Eriksen Flanker and spatial Stroop attention test under four sound conditions (silence, noise AVAS, multi-tone AVAS, and two-tone AVAS) while EDA was continuously recorded. All signals were presented at realistic indoor levels (LA,eq≤21.5 dB), simulating closed-window exposure in modern buildings using a wave field synthesis-based auralization approach. While attention performance was unaffected, physiological and subjective responses varied significantly across conditions, with the two-tone AVAS resulting in the highest EDA, mental demand, and annoyance ratings. These findings suggest that highly tonal AVAS signals, despite potential benefits for detectability, may impose a greater perceptual and physiological burden on non-involved listeners such as residents. The results highlight the need for AVAS designs that strike a balance between safety and minimal disruption to the surrounding acoustic environment.