In 2025, the European Union Agency for Railways (ERA) established a Topical Working Group (TWG) on parked trains as a temporary expert body tasked with defining the concept of parked trains, setting associated noise limits, and developing assessment methodologies to support TSI revisions. This is to facilitate the implementation of the Single European Railway Area by 2028.

The group brings together sector representatives, National Safety Authorities (NSAs), independent experts and users, with the UIC Noise Vibration Sector and Community of European Railway and Infrastructure Companies (CER) Noise groups taking part by consolidating technical knowledge and aligning sector positions to support the discussions.

In line with this target and sector’s needs, The NOise and VIbration Technical Advice (NOVITÀ) framework, as a core instrument providing technical support to the UIC Noise and Vibration Sector, has already made key analytical documents available to advance the discussion, including:

• 2023 - S structured assessment of operational and technical solutions addressing noise from parked and stationary trains
• 2022- A review of nuisance and health impacts of railway noise
• 2025 - IRS 75718: Measurement procedures and noise data collection criteria, establishing a harmonised assessment methodology aligned with ISO 3095:2025

These outputs have helped define the problem, identify dominant noise sources, and clarify the gaps in current regulatory approaches.

New study: Closing the evidence gap

Building on these results, a new study has been launched under the NOVITÀ framework to address a critical missing element: A European-scale estimate of the number of people potentially affected by noise from parked trains. UIC has signed a contract with Tommasi & Tommasi srl to ensure the delivery of a robust population exposure assessment directly supporting the work of the ERA TWG.

Defining the problem and scope of the UIC study

Noise from parked trains is primarily generated by auxiliary systems (e.g. eating, ventilation, and air conditioning (HVAC), compressors, cooling fans, and power supply equipment) and can persist for several hours, particularly during night-time stabling at depots, stations, and shunting yards. While the issue has been accounted for at local level in several UIC member countries, currently, no consolidated assessment exists of how many people across Europe may be exposed to this, nor how significant it is relative to other railway noise sources.

The UIC study is designed to provide a European-scale, order-of-magnitude estimate of population exposure, based on consistent and scalable methodologies. Key components include:

• European-wide inventory of train stabling sites across a representative set of countries, identified through a geospatial pipeline that combines OpenStreetMap data with AI-assisted satellite image analysis to systematically locate and classify depots, stabling yards, and terminus sidings.
• Population exposure estimation, using Eurostat population data to assess how many residents live in proximity to identified stabling locations, in collaboration with the European Environment Agency (EEA) Noise Group.
• Noise characterisation and regulatory analysis, consolidating existing measurement data and comparing national regulatory approaches, including the varying treatment of parking noise (in terms of railway noise versus industrial noise), to inform the upcoming Technical Specification for Interoperability relating to the subsystem ‘rolling stock – noise’ (TSI NOI) revision.
• UIC member engagement programme, with bilateral consultations, a benchmarking workshop, and an approval round to integrate operational knowledge from infrastructure managers and railway undertakings directly into the study.

“There is currently no systematic picture of how many Europeans live near locations where trains are parked overnight, and consequently no evidence base for deciding whether European-level limit values are needed. This study aims to fill that gap by combining open geospatial data, satellite imagery, and input from railway operators across Europe, so that the policy discussion ahead of the 2028 TSI NOI revision can be grounded in transparent, reproducible evidence” says RafDouglas Tommasi, from Tommasi & Tommasi, when asked about the study.

The Tommasi &Tommasi srl team brings together expertise in geographic information systems (GIS), environmental noise assessment, and EU regulatory frameworks, including experience with the European Commission’s CNOSSOS-EU noise method and the Environmental Noise Directive.

Dissemination and next steps

Results will be shared in a technical report by September 2026 and presented at the ERA TWG meeting on 9 September 2026. The results are also expected to support discussions at the UIC Railway Noise Day activities planned during the UIC Sustainability Action Week (19-23 April 2027).

Stakeholders interested in contributing to the study or supporting this work are encouraged to join UIC groups. For further information or to express interest in collaboration, please contact noisevibration at uic.org.