False Alarm Effects in Early Warnings for Emergency Vehicles: Exploring Drivers’ Move-Over Behavior

Weibull, Kajsa; Lidestam, Björn; Prytz, Erik · 2024 · Crossref

DOI: 10.1177/00187208231216835

archive: archived pipeline: cataloged verified

Get this paper ↗ (DOI — opens at the source; we link to it, we don't host it)

Summary

This study investigates the efficacy of Emergency Vehicle Approaching (EVA) warnings in promoting driver move-over behavior and examines how false alarms, driver experience, and warning modality influence compliance. The research addresses a critical safety gap: while sirens and lights are standard for alerting drivers to emergency vehicles, they are often difficult to localize or detect due to vehicle soundproofing, leading to delayed reactions. EVA warnings offer an early in-car notification to facilitate safer maneuvers, but their reliance on predicted paths introduces a risk of false alarms, which may undermine system credibility and future compliance. The researchers conducted a driving simulator study with 110 participants, divided into inexperienced (18–24 years old, ≤5 years licensed) and experienced (40–65 years old, ≥10 years licensed) groups. Participants underwent three emergency vehicle interactions during a 30-minute highway drive. The experimental design included a control group receiving no warnings and experimental groups receiving either true or false auditory or visual warnings 15 seconds before the emergency vehicle overtook them. Move-over time, defined as the seconds taken to shift 2.5 meters from the lane center after the emergency vehicle became visible, served as the primary performance metric. Statistical analyses, including split-plot factorial ANOVAs and planned contrasts, evaluated the effects of warning presence, verity, experience, and modality. Results indicated that drivers receiving EVA warnings moved over significantly faster than the control group. Move-over times decreased across successive events, suggesting a learning effect. Crucially, false alarms impaired subsequent move-over behavior. In the third event, drivers who had received only true alarms moved over significantly faster than those who had experienced at least one false alarm. However, no significant difference was found between drivers who received a majority of true alarms versus a majority of false alarms, nor between those receiving one versus two false alarms. The study found no significant differences in move-over behavior based on driver experience or warning modality (auditory vs. visual). The findings confirm that EVA warnings effectively accelerate driver compliance but highlight that false alarms can degrade this benefit by reducing future willingness to comply. The lack of difference between inexperienced and experienced drivers contradicts prior suggestions that novices benefit more from such systems, potentially due to simulator familiarity among younger participants. The study concludes that while EVA systems are beneficial, their design must minimize false alarms to maintain credibility. Future research should explore the order effects of false alarms and validate these findings in naturalistic driving environments to better understand long-term compliance dynamics.

Provenance

The full processing record for this entry. Every stage of this paper's journey through the pipeline is logged — what ran, with which tool and model, how many attempts it took, and when it last completed.

Summary generated by qwen3.6-27b-prismaquant on 2026-06-09; verification: verified.

Topics

Ranked by relevance to this paper. Hover a topic for its definition.

• auditory warnings
• warning design
• automation surprise

Information type

What kind of knowledge this paper contributes, grouped by family — independent of topic (what it is about) and method (how it was studied).

• Empirical Findings: behavioral performance data