The world is becoming increasingly mobile, and the railway sector is evolving to meet this demand. Rising traffic volumes are putting greater pressure on existing rail infrastruc- ture, while modernization, expan- sion, and new construction projects are becoming more frequent. At the same time, railway contractors face growing challenges, including tigh- ter schedules, higher train speeds, increasing project complexity, labor shortages, and escalating costs. As a result, the impact of Europe’s mobility transformation is being felt across the railway construction in- dustry more strongly than ever.

One System, Flexible Application

Every railway worksite is unique. Work pro- cesses, site conditions, and regulatory re- quirements differ from country to country and from project to project. To address these varying demands, ZÖLLNER offers flexible, modular warning systems that can be configured for many different applica- tions while maintaining the highest level of safety.]

The operating principle remains straight- forward and reliable: an approaching train is detected, the information is transmitted to a control unit, and an audible warning is issued to personnel on site. Detection can be achieved through various methods, in- cluding track-mounted sensors, trackside lookouts, or notifications from signaling systems. Depending on operational re- quirements, the warning can be provided through collective warning systems or per- sonal warning devices. These systems can be placed throughout the worksite or ins- talled directly on construction equipment.

The integrated Autoprowa® effect conti- nuously adjusts the volume of the acoustic warning signal between 97 and 126 dB(A), ensuring it is always loud enough to alert workers effectively while avoiding unne- cessary noise for nearby communities and the surrounding environment. Communi- cation between system components is just as adaptable. Solutions can be connected via cable, radio, or a combination of both, allowing each project to benefit from the most suitable configuration.

Global Expertise, Local Solutions

With decades of international expertise, ZÖLLNER works closely with customers around the world to provide solutions that meet local operational needs and regula- tory requirements. The following examples illustrate several ways in which ZÖLLNER warning systems can be used to enhance safety and protect people working on or near railway tracks.Ev

Reliable Protection for Smaller Railway Worksites – Fast Installation and Maximum Flexibility

Mobile and short-term track worksites re- quire warning systems that are quick to deploy, easy to operate, and adaptable to changing conditions. The ZÖLLNER Mobile Radio Warning System (MRWS) is widely used for these applications, enabling loo- kouts to detect approaching trains and trig- ger clear warnings for workers on site. For small teams and limited work areas, the compact ZPW-12 can serve as both war- ning device and control unit, minimizing setup time and logistical effort.



The MRWS can also be enhanced with ad- ditional functions tailored to specific opera- tional requirements. In France, for example, voice communication and real-time posi- tioning have been integrated to support cooperation between the safety manager and trackside lookouts. Required warning distances are monitored automatically, and immediate alerts are issued if minimum dis- tances are not maintained.

Real-time position monitoring allows for the safety manager (ASP in France) to view the actual location of all relevant lookouts in regards to the worksite at all times. Should the distance of the lookout to the worksite ever be less than the specified sighting distance, an alarm sounds alerting booth the safety manager as well as the lookout who can subse- quently correct his position immediatly. This allows the lookouts to focus fully on the tasks as they can safely rely on the monitoring system to make sure that their positioning is in line with the requirements.

The ZPW-12 can function as warning device and control unit simultaneously allowing for especially slim configurations and therefore reducing transportation, handling and logistic efforts.

Specialized applications are available for challenging work environments. Vegetation maintenance along railway lines often invol- ves high noise levels, personal protective equipment, and dispersed workgroups. To address these conditions, ZÖLLNER deve- loped the ZVW Vegetation Warning System, which delivers warnings directly through hearing protection and supplements them with visual LED alerts in the face shield.



The MRWS is also well suited for stationary small worksites. In New Zealand, approa- ching trains are detected automatically by trackside sensors such as the F500 induc- tive train detector, which can be installed within minutes using a magnetic mounting system. Combined with the ZPW-12, this creates a compact and efficient warning solution that reduces equipment require- ments while maintaining a high level of safety.

The magnetic clasp allows for quick and easy installa- tion of the track sensor in just a few seconds.

Engineered for Complexity – Warning Systems for Medium and Large Railway Worksites

THE ZRT-30 allows for the combination of the cable- based warning system with radio-based warning devices further adding to the possible configurations..

For larger worksites, fully automatic war- ning systems provide maximum safety with minimal operational effort. In Finland, to name just one example, the MRWS uses track sensors to automatically activate and clear warnings. Strategically placed war- ning devices ensure workers are alerted where protection is needed most.

The MRWS is also widely used in Germany, where fully automatic operation is required for worksites longer than 400 meters. War- ning devices can be mounted directly on construction machinery to provide additional protection whenever needed.

On extensive construction sites, workers are often spread across large areas and constantly on the move. In these situations, warning devices are arranged in a continuous chain to provide uninterrupted protection along the entire worksite.

Depending on project requirements, this can be achieved using radio-based MRWS components or the proven Autoprowa® cable-based system. For long-term pro- jects, cable systems are often preferred due to their fully automatic operation and low maintenance requirements. With more than 100,000 deployments worldwide, the system has proven its reliability in a wide variety of operating environments.

For maximum flexibility, ZÖLLNER’s ZRT- 30 Radio Transceiver enables seamless integration of the Autoprowa® cable-based system with the MRWS. This allows additional warning devices, including machine mounted systems, to be added quickly whenever site conditions change. The result is a flexible, cost-effective warning solution that can be adapted to virtually any worksite while maintaining the highest safety standards.

The cable-based warning system has been deployed on over 100.000 worksites all over Europe and is especially suited for extensive projects.

Warning Systems Mounted Directly on Construction Machinery

Railway construction and track renewal pro- jects frequently require personnel to work in close proximity to adjacent live tracks, making effective warning systems essential for maintaining a safe working environment. To address this challenge, ZÖLLNER’s ma- chine-mounted warning system is perma- nently installed on construction machinery and powered directly by the machine itself. The system is activated through the site’s warning infrastructure, providing reliable and continuous protection for workers ope- rating near active rail lines.

The solution has been successfully de- ployed across Europe for many years, with installations in countries including Poland, Germany, Austria, and France. Its proven performance and safety benefits have led to growing adoption throughout the industry.

Increasingly, rail operators are choosing to equip their machinery with dedicated war- ning systems even when regulations do not mandate their use, recognizing the added layer of protection they provide.

To further enhance safety in areas where visibility may be restricted, such as access points, crossings, and other high-risk locations, additional visual reminder lights can be fitted to the machinery. These clear visual indicators help ensure that approaching train movements are immediately recognizable to all personnel working nearby, improving situational awareness and reducing the risk of accidents.

ZÖLLNER has worked alongside Polish authorities to implement ZÖLLNER warning systems on Polish worksites.

(Semi-)Permanent Warning Systems for Recurring Worksites

For railway sections that require regular maintenance, inspections, or patrol activi- ties, semi-permanent Automatic Track War- ning Systems (ATWS) offer a practical and efficient solution. Key components such as train detection, transmitters, and control units remain permanently installed on site, allowing protection to be established qui- ckly whenever work is planned. Only the warning devices need to be deployed and connected, reducing setup time and enabling work to begin without delay. Future developments will also allow workers to connect directly to the system via perso- nal warning devices such as the ZÖLLNER WADSON, providing individualized alerts and an additional layer of safety.

The machinery warning system keeps people safe where loud equipment and limited visibility could lead to dangerous situations.

Automated and Safe – Temporary Protection for Level Crossings

When a level crossing experiences a tech- nical failure, repairing the installation or replacing it with a new system is a process that takes time and cannot be completed overnight. During this period, safe pas- sage for both road and rail traffic must be maintained without causing unnecessary disruption to operations. Traditionally, this has been achieved using temporary level crossing protection systems or manual safeguarding measures that require one or more attendants on site. These atten- dants carry significant responsibility, as even a single error can have serious conse- quences.

A-CROSS provides a new approach to this challenge. Designed as a fully automated temporary level crossing protection system, it can be deployed wherever a conventio- nal temporary protection system would normally be used, eliminating the need for a dedicated crossing attendant. By taking over the operational tasks traditionally per- formed by on-site personnel, A-CROSS also relieves them of a substantial share of the associated responsibility.

Developed to SIL 3 requirements, A-CROSS delivers a higher level of safety than exis- ting temporary level crossing protection solutions. The system combines axle coun- ting technology for automatic activation and release with proven PLC-based temporary crossing protection components. Its sca- lable architecture supports up to 10 bar- rier drives, 24 warning signals and 8 track contacts, enabling a wide range of level crossing configurations to be replicated. In addition, up to four monitoring signals can currently be installed at a distance of 100 meters from the crossing to provide train drivers with clear information about the crossing status, with further expansion planned for the future.



Because no personnel are required on site during operation, system faults are re- ported automatically to the responsible au- thority via remote monitoring. This ensures reliable and continuous protection while reducing operational effort.

ZÖLLNER in Poland – working together for safer track worksitesa

The temporary level crossing system A-CROSS runs fully automatic and can be flexibly configurated and easily installed to protect both rail and road traffic.

For 15 years, ZÖLLNER has worked closely with Polish authorities and railway stakehol- ders to continuously improve safety stan- dards on track worksites. Over the years, significant progress has been achieved, and today the topic of Automatic Track Warning Systems remains more relevant than ever.

A recent update to the Id-18 guideline marks an important step in enhancing safety at trackside work sites in Poland. Under the revised requirements, construction and maintenance activities carried out within the rail corridor are expected to be protec- ted primarily through the use of Automatic Warning Systems (in Poland known as ASO - Automatyczny System Ostrzegania). The objective is to provide reliable and timely warnings to personnel working on or near the track, thereby reducing the risk of acci- dents and improving overall worksite safety.

By placing greater emphasis on automated warning technologies and comprehensive planning, the updated Id-18 guideline sup- ports a more systematic and proactive approach to railway worksite safety Meeting these requirements and delivering real value for everyone involved requires ongoing dialogue and knowledge exchange. After all, a warning system can only provi- de reliable protection while supporting efficient worksite operations if its planning, configuration, and deployment are carefully adapted to the specific site conditions and the workflows of the people using it.

This is why both proper training and a well-prepared Work- site Protection Plan are of such essential importance.



That is why the ZÖLLNER Academy offers tailored, comprehensive training programs designed to provide users with both the knowledge and practical skills required for safe and efficient system operation. Ex- perienced instructors with many years of hands-on expertise deliver both theoretical and practical training, ensuring a strong connection between learning and real-wor- ld application.

Support does not end when the training is completed or the system is commis- sioned. ZÖLLNER remains a trusted partner throughout the entire lifecycle of the sys- tem. Whether reviewing safety plans, sup- porting site-specific system configurations, liaising with authorities, or providing imme- diate assistance in the event of a technical issue on site, the ZÖLLNER service team is available 24/7 and never more than a phone call away.

At the heart of this approach lies partnership. One thing is certain: meaningful progress can only be achieved together. By com- bining expertise, practical experience, and a shared commitment to safety, we can conti- nue to raise standards and work towards the common goal of providing the highest possible level of protection for everyone working on railway construction and main- tenance sites.

ZÖLLNER Polska joins the UTK Safety Culture Declaration, reinforcing its commitment to responsible action and the continuous advancement of railway safety in Poland.

Partnership is key to implementing lasting solutions and keeping people safe where it matters most.

Who is ZÖLLNER?

As one of the world’s leading providers of automatic warning systems, ZÖLLNER has been safeguarding people working on or near railway tracks for decades. Based in Kiel, Germany, the company marks its 80th anniversary this year and has grown from a regional family business into a globally recognized technology leader.

By bringing development, production, and service together under one roof, ZÖLLNER ensures the highest standards of quality and efficiency. Its modern facilities, combined with a 24/7 service network, allow the company to deliver trusted safety solutions used around the world.

ZÖLLNER is synonymous with innovation, dependability, and a strong commitment to its core mission: protecting people.

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