EN 16683: Europe’s New Standard for Train Safety Communication

What is EN 16683: Railway Call for Aid and Communication Devices?

EN 16683 is a European Standard that specifies the technical and functional requirements for ‘Call for Aid’ and communication devices installed on railway passenger rolling stock. The primary purpose of this standard is to ensure a reliable, clear, and standardized method for passengers to request assistance or report an emergency to the train crew or a central control point.

This system, often recognized by passengers as an emergency intercom or help point, is a critical safety feature. EN 16683 defines its design, operation, and performance criteria to guarantee functionality under various operating conditions, enhancing both passenger safety and confidence.

Core Objectives of the Standard

The implementation of EN 16683 aims to achieve several key objectives within the railway industry, directly impacting safety, accessibility, and operational consistency:

• Standardization: It creates a uniform user experience across different fleets and operators, ensuring passengers immediately recognize how to call for help, regardless of the train they are on.
• Reliability: The standard mandates robust design and testing to ensure the device functions correctly when needed most, including during power fluctuations or in harsh environmental conditions.
• Accessibility: It incorporates requirements from the Technical Specifications for Interoperability for Persons with Reduced Mobility (TSI PRM), making the devices usable by all passengers, including those with visual, hearing, or physical impairments.
• Clarity of Communication: It sets performance benchmarks for audio quality to ensure that conversations between the passenger and crew are intelligible over the background noise of a moving train.
• Unambiguous Operation: The standard requires clear visual and audible feedback for the user, confirming that a call has been initiated, acknowledged, and connected, eliminating uncertainty in a stressful situation.

Key Technical Requirements of EN 16683

EN 16683 outlines a detailed set of technical specifications that manufacturers and operators must adhere to. These requirements cover the entire system, from the passenger interface to the communication protocol.

Activation and User Interface

The passenger-facing part of the device must be intuitive and resistant to accidental activation. Key requirements include:

• Push-Button Design: The activation is typically a push-button that is clearly marked and physically protected, often by a flap or a design that requires a deliberate press.
• Pictograms and Symbols: The device must be labelled with internationally recognized symbols (e.g., an SOS or a telephone handset icon) for immediate identification.
• Tactile Information: For visually impaired passengers, the device must include tactile markings and/or Braille.
• Color and Contrast: The device and its immediate surroundings must have sufficient color contrast to be easily located, in compliance with accessibility standards.

Audio Communication

The quality of the audio link is paramount for the system’s effectiveness. The standard mandates several critical audio performance characteristics.

• Full-Duplex Communication: The system must support full-duplex audio, allowing both the passenger and the crew member to speak and be heard simultaneously, just like a standard telephone call. This is crucial for natural and efficient conversation, unlike half-duplex (walkie-talkie) systems where only one person can speak at a time.
• Speech Intelligibility: The standard sets minimum requirements for audio clarity, often measured using a Speech Transmission Index (STI) or similar metrics. This ensures the conversation is understandable above the train’s ambient noise.
• Volume Levels: The loudspeaker volume must be sufficient to be heard clearly, and the microphone must be sensitive enough to pick up the passenger’s voice without them needing to shout.

Visual and Audible Indications

To provide confidence to the user, the system must provide clear feedback throughout the call process:

• Call Initiated: Upon activation, an audible tone sounds, and a visual indicator (typically a flashing LED light) on the device confirms the call has been sent.
• Call Acknowledged: When the crew or control center receives the call, the visual indicator may change state (e.g., from flashing to a solid light) to show the call has been received and is waiting to be answered.
• Communication Established: Once a crew member answers, a voice message or another distinct tone may indicate that the two-way communication channel is open.

Accessibility for Persons with Reduced Mobility (PRM)

EN 16683 works in conjunction with the TSI PRM to ensure devices are fully accessible. This includes specific rules for:

• Location: Devices must be installed at specific heights and locations, such as in designated wheelchair spaces and accessible toilets, to be reachable by a seated person.
• Ergonomics: The force required to operate the button must be low enough for individuals with limited strength.
• Information: As mentioned, Braille and tactile indicators are mandatory to assist visually impaired users.

EN 16683 Requirements Summary Table

The following table provides a high-level comparison of the key technical pillars defined within the EN 16683 standard.

Scope and Application

The EN 16683 standard is applicable to all new mainline passenger rolling stock operating within the European Union. While not retroactively enforced on older vehicles, it serves as the definitive benchmark for any major refurbishment or modernization projects involving passenger communication systems. It is distinct from, but often integrated with, other onboard systems like the Public Address (PA) system and Passenger Information Systems (PIS).

Conclusion: The Importance of EN 16683 in Modern Railways

EN 16683 is more than just a technical document; it is a cornerstone of modern railway passenger safety philosophy. By standardizing the design and performance of call-for-aid devices, it ensures a consistent and reliable safety net for passengers. This harmonization builds public trust in rail travel, meets stringent regulatory demands for safety and accessibility, and provides train operators with a clear framework for implementing a life-critical system effectively and responsibly.