How are modern train interiors designed? .

Over the past decade, the passenger rail industry has undergone a true transformation. Rising passenger expectations, the increasing focus on sustainability, and rapid technological progress have redefined the approach to train design. In a previous article, we explored vehicle exteriors in: The new face of passenger trains – modern rail vehicle front sections and cladding.  

But how are train interiors designed today? Ergonomics, travel comfort, and accessibility are now baseline requirements—not differentiators. Rolling stock manufacturers must also comply with stringent regulations, diverse operator expectations, and strict time and cost constraints. 

This article covers: 

• the key stages in the interior design process for modern passenger trains, 
• applicable norms and technical standards for interior components, 
• how digital simulations support design and validation, 
• challenges faced by OEMs and interior component suppliers, 
• trends shaping the trains of the future, 
• how to align passenger expectations with regulatory and technical requirements. 

Passenger experience as a design foundation 

In rail transport, “user experience” goes beyond a comfortable seat—it encompasses the entire journey from boarding to disembarking. Travel comfort is largely shaped by interior ergonomics: optimized seat profiles, clear space for movement and luggage, and intuitive access to information. Acoustic design is equally crucial—noise-dampening materials and vibration-reducing solutions significantly improve travel conditions, enabling passengers to work or relax. 

Modern LED lighting enhances the onboard atmosphere and contributes to user safety. Accessibility is also fundamental: wide aisles, dedicated spaces for passengers with reduced mobility (PRMs), and intuitive signage are key elements. A holistic approach is essential to create environments that meet both passenger expectations and operator requirements. 

Interior design standards for Rolling Stock 

Train interior design must fully adhere to a range of technical standards, ensuring both safety and passenger comfort. Among the most important are the TSI PRM (Technical Specifications for Interoperability – Persons with Reduced Mobility), which define requirements for accessibility – including minimum aisle widths, button placements, and designated wheelchair spaces equipped with proper fittings. 

EN 45545 is the European standard regulating fire safety for materials and components used in train interiors. Compliance requires that cabin elements such as seats, wall panels, and enclosures pass strict tests for flammability, smoke emissions, and toxicity. 

Additional standards address acoustic and climate-related parameters—including maximum noise levels, thermal insulation effectiveness, and HVAC system performance. These factors directly impact both comfort and energy efficiency. 

Examples of critical technical requirements include: 

• Minimum clearances for wheelchair spaces, 
• Fire resistance of interior materials in line with EN 45545, 
• Interior noise levels not exceeding specified dB(A) thresholds, 
• Temperature and ventilation control in passenger compartments, 
• Use of both visual and auditory passenger information systems. 

Meeting these standards requires certified documentation. Only then can rolling stock be approved for market operation and confirmed as safe and functional. 

The Interior design process 

Designing a modern train interior requires the careful integration of aesthetics, technical requirements, and onboard systems. The process typically includes: 

• Needs Analysis – identifying requirements for passenger comfort, flow, accessibility, and route specifics (e.g., regional vs. long-distance lines), 
• Concept Design – creating layout variants with ergonomic considerations and flexibility for diverse passenger needs, 
• Virtual Prototyping & Simulation – developing and computationally verifying detailed 3D models, including integrated systems, 
• Design Validation – optimizing and verifying compliance with technical and functional specifications before building physical prototypes. 

System integration is a vital part of this process and includes: 

• HVAC systems, 
• Passenger information and multimedia systems, 
• Wi-Fi networks, 
• Safety and surveillance systems. 

All installations must fit into confined spaces, function seamlessly together, and meet fire safety and acoustic standards. 

To reduce weight and improve energy efficiency, engineers use lightweight materials and composite structures that minimize axle loads, lower energy consumption, reduce operating costs, and simplify assembly and maintenance. 

Digital simulations and virtual validation 

Advanced engineering simulations are foundational to the modern design process, enabling comprehensive validation before any physical prototypes are built. 

Common simulation methods include: 

• CFD (Computational Fluid Dynamics) – used to analyze airflow and temperature distribution within the cabin, optimizing HVAC system performance and thermal comfort, 
• FEA (Finite Element Analysis) – to assess the structural integrity of seats, panel fastenings, ceilings, and sanitary components, 
• Passenger Flow Simulation – models boarding and alighting dynamics, evaluates internal traffic flow and evacuation safety, 
• Acoustic Simulations – predict noise sources, vibration levels, and sound propagation, aiding in effective noise control design. 

Business benefits of simulation-based design include: 

• Shorter development cycles and faster time-to-market, 
• Fewer costly physical prototypes, 
• Early detection of design flaws, 
• Easier certification preparation with simulation-based standard compliance. 

With CAE-supported virtual validation: rolling stock manufacturers can reduce risk, control development costs, and ensure high-quality implementation across platforms. 

Key challenges for interior component manufacturers 

Designing and manufacturing modern train interiors comes with several technical and organizational challenges. 

One major issue is integrating modern subsystems into existing rolling stock platforms—many of which are based on designs from previous decades. This means retrofitting passenger information systems, Wi-Fi, and HVAC units into limited mounting space and legacy electrical infrastructure. (See also our article “Rolling Stock Modernization – Giving Old Trains a New Life.” –

Manufacturers must also accommodate varied operator requirements—from interior finish preferences and national/regional standards to accessibility rules. In addition, they often face tight delivery schedules and cost constraints, demanding a flexible development and production approach. 

Another critical challenge is managing technical documentation and certification. Each component must be verified in line with TSI PRM, EN 45545, and local safety regulations, involving extensive documentation and testing. 

For more insights into platform-level constraints, see our article: “Challenges in Rail Vehicle Design.”

Interior design trends in rail transport 

The focus of modern rail interior design is increasingly on creating exceptional passenger experiences and supporting sustainable development. Key trends include: 

• Personalized Spaces – travelers expect tailored environments. In response, manufacturers are developing dedicated zones, such as workspaces with USB ports and tables, family compartments, and quiet zones. These enhancements boost passenger comfort and help operators differentiate their services. 
• Smart Technologies & Connectivity – real-time passenger information, onboard Wi-Fi, and multimedia systems are becoming standard. These tools support work, entertainment, and travel planning. 
• Sustainability & Recycled Materials – growing environmental awareness drives the use of lightweight composites, recycled materials, and solutions that reduce energy consumption and noise emissions. 
• Inclusive Design – wide aisles, dedicated wheelchair areas, high-contrast signage, and ergonomic handrails create accessible interiors for passengers with reduced mobility, seniors, and families. Inclusive design enhances travel comfort and ensures compliance with TSI PRM standards. 

Merging expectations with technology 

Designing modern train interiors is where ergonomics, smart technology, stringent safety regulations, and rising passenger expectations converge. A comprehensive approach—from user needs analysis to digital simulations and integrated system certification—enables the creation of welcoming interiors that help operators stand out in the transport market. 

Explore how Endego designs the rail systems of the future and discover our services in rolling stock design and development. We support OEMs and railway operators in transforming user requirements into tangible, optimized solutions. 

📩 Contact us to discuss your project.