[Publication] Accompanying Expertise on the Roadworthiness Package

Background

Despite the goals outlined in the EU Road Safety Policy Framework 2021-2030 (EC 2020b), the number of accidents and fatalities on European roads remains unacceptably high. The noted main intervention areas are:

1. Infrastructure – safe roads and roadsides (EC 2020b, p. 15);
2. Safe vehicles (EC 2020b, p. 16);
3. Safe road use (EC 2020b, p. 19); and
4. Fast and effective emergency response (EC 2020b, p. 22).

Contributing factors include unsafe driving behaviours (area 3), and the continued use of inadequately maintained or inherently unsafe vehicles (area 2). Preventing road crashes or mitigating their severity constitutes a critical objective in achieving the European Union’s Vision Zero target by 2050.

To increase vehicle safety (area 2), the Roadworthiness Package (RWP) introduces updated and novel test procedures for the PTI^[1], as an amendment to Directive 2014/45/EU and for RSI^[2] as a revision of Directive 2014/47/EU. The implementation of these measures presents significant challenges, particularly in defining appropriate test frequencies, ensuring comprehensive test coverage and adapting inspection protocols to accommodate increasingly sophisticated electronic systems in modern vehicles.

The RWP focuses on safety-critical vehicle components and systems, high-voltage systems of electric vehicles, and emission-related systems. To address these systems, the monitoring must cover both nitrogen oxides (NOx) and particulate matter. A limit for particulate matter (PM in [mg/km] or [mg/kWh]) is set primarily for diesel-powered vehicles because they are the main source of this pollutant. Ultrafine particles are measured via Particle Number (PN in [counts/cm³]), a metric that is especially relevant for diesel engines equipped with particulate filters and for direct-injection gasoline engines.

Objective

In view of updating the EU legislation on roadworthiness testing of vehicles [2014/45/EU (EU 2021) and 2014/47/EU (EU 2022)], this expert report summarises and evaluates the proposals of the RWP (EU 2025a) (EU 2025c) and other relevant technical papers.

The objective of this report is to provide an independent assessment of the technical approach underpinning the PTI and RSI directives with respect to safety-critical and emission-related electronic systems in vehicles, and to evaluate the technologies used for remote emission sensing.

Results

All analysed documents underscore the need to intensify technical inspection of motor vehicles across the European road network.

A principal finding of this assessment is the necessity to define minimum content of data storage protocols and testing procedures across Member States and vehicle manufacturers, including the definition of responsibilities for data provision among stakeholders. It is proposed to adapt the PTI test frequency either stepwise or with a transition period to 3-1-1-1 schedule, i.e. after 3 years for new vehicles, followed by annual testing.

Moreover, the performance data for safety- and emission-related features measured by OBD and OBM should be made accessible to PTI/RSI tools. Deviations in components may be addressed through specific electronic test procedures (ePTI), tailored by the original equipment manufacturer (OEM) and based on test assignments linked to the individual vehicle identification number (VIN).

Testing protocols for both PTI (including ePTI) and RSI should be guided by a standardised digital tool, accessible in each Member State’s official language and available to all authorised test centres. This tool shall provide step-by-step guidance through all testing phases, ensuring consistency and compliance across the European Union. Test outcomes shall be automatically recorded within national databases. Cross-border data exchange shall be facilitated through synchronisation via a centralised data exchange platform, such as MOVE-HUB (EU 2025c, p. 139).

By focusing on the roadworthiness of powered vehicles, the technical integrity of emission-related components and systems can be evaluated during PTI and RSI. To identify high-emitting vehicles, remote sensing technologies can be employed. Remote sensing of exhaust emissions should be divided into two distinct methodologies: plume-chasing techniques, designed for the targeted testing of clearly high-emitting vehicles, and stationary^[3] emission sensing systems, which enable continuous monitoring of traffic emissions and can evaluate a substantial segment of the registered vehicle fleet (Borken-Kleefeld, Jens, et.al. 2023, p. 10). However, because exhaust gases are significantly diluted by atmospheric air, the overall measurement accuracy of stationary emission sensing systems is limited for detecting high-emitting vehicles (JRC 2020). Applying a detection limit that is 2.5 times the emission limit will avoid false positive detections.

For electric vehicles (EVs), PTI testing of high-voltage systems must extend beyond on-board diagnostic capabilities to also assess ageing components such as ground contacts, wires and connectors (ZVEI – German Electrical and Electronic Manufacturers‘ Association 2025, p. 3–5). Particular emphasis should be placed on equipotential bonding and insulation resistance testing to mitigate the risk of electrical shock. All OEMs must demonstrate how these checks can be performed effectively during PTI with minimal mechanical intervention.

In summary, the RWP primarily updates the requirements and procedures for PTI and RSI in relation to safety- or emission-related electronic systems, new testing requirements arising from the introduction of EVs, emission monitoring, and the detection of defective or fraudulently manipulated emission reduction systems. These changes are consistent  with the EU Road Safety Policy Framework (EC 2020b).

[1]      PTI: Regular technical inspections of vehicles, to minimise the number of defects and the use of risky vehicles in public traffic.

[2]     RSI: Technical inspections of vehicles beside the road. Vehicles are chosen stochastically or by preselection, using a risk rating system.

[3]     Stationary emission sensing systems are stationary measurement devices, mounted both vertically (top-mounted) or horizontally (crossroad) across the road to monitor the emission plumes of the passing vehicles.