Safety Use Case Analysis and Likely Benefits of DMS: Examination of Driver States and Scenarios under the Euro NCAP 2026 Driver Engagement Protocol. Proceedings of the 28th International Technical Conference on the Enhanced Safety of Vehicles (ESV). 12 - 15 May 2026; Toronto, Canada.

Driver drowsiness and distraction are significant risk factors for crashes. To address this EuroNCAP expanded its Driver Engagement Protocol, effective 1 January 2026. Manufacturers are encouraged to implement solutions aimed at reducing the incidence of these behaviours. The Protocol demands that once these behaviours are detected, drivers are warned and the vehicle intervenes by increasing the sensitivity of forward collision systems and lane keeping systems, and if required to take over the vehicle to bring it to a safe stop. The aim of this paper was to examine the proportion of crashes this Protocol could impact and to estimate the likely cost-effectiveness of the driver monitoring system required. Real-world crash data was used to establish the proportion of serious injury crashes that the risk factors targeted by EuroNCAP were seen. Administrative data, cost of injury values, and the unit cost of fitting driver monitoring systems (DMS) into new vehicles was used to calculate benefit cost ratios (BCRs) for implementation. Distraction targeted in the EuroNCAP Protocol was a common contributing factor to crashes (21.6%; mobile phone use: 3.8%) as was drowsy driving (25.4%; fell asleep: 7.9%), alcohol (11.2%) and drug impairment (12.7%), and sudden medical events (10%). The BCRs demonstrated implementation of the Protocol underpinned by DMS would be highly cost effective. Sensitivity analysis across effectiveness levels and implementation costs showed the findings to be robust. The findings highlight the significant safety potential and cost-effectiveness of DMS in addressing behaviours specified in the EuroNCAP Driver Engagement Protocol. Further work is needed before assessing the likely efficacy of the Protocol in addressing alcohol and drug intoxication. Limitations include that estimates of the efficacy of the interventions were used. Nonetheless, the analysis demonstrates that significant reductions in road trauma can be achieved by implementation of the Protocol with this being highly cost-effective