The emergency services and the public entrust us with their lives

The German Federal Agency for Technical Relief (THW) has relied on Leica Geosystems, part of Hexagon, technology to assess hazardous situations for years.

Inside the mind of a crash investigator

Kevin Kärcher, THW technical advisor in Weingarten (Bavaria), talks about the benefits and experiences of the Emergency Site Safety System (ESS) with Leica Geosystems' technology in crisis scenarios: "The device must always work in every situation, and it does! It does so 100% of the time. The system has never let us down."


Q: What is the primary purpose of the Emergency Site Security System (ESS)? 

The ESS and our work primarily serve to protect and safeguard emergency services. They entrust us with their lives. As such, our team and the tools we use must demonstrate absolute reliability, professionalism and effective implementation, especially when interpreting measurement data at the scene of the incident.

Technisches Hilfswerk - Einsatz Augsburg_2021

For example, when standing in a small personnel carrier next to a building in flames at half past three in the morning and interpreting measurement data. Then, when firefighters enter this burning building, they rely on our work for their lives. 

THW - standing in a small personnel carrier next to a building in flames. Augsburg fire


Q: So, is the ESS something special in the THW's operational catalogue?

Yes, because it is one of the first options for protecting the emergency services. The system's process involves data exploration, security, and support. Calibration is done initially before data collection starts; finally, the captured data is interpreted. If there are no immediate dangers, the data is utilised to execute the necessary safety measures based on the information amassed during the exploration phase.

THW - Augsburg fire 2021_THW Weingarten


Q: So, measuring alone is not enough.

Yes, merely measuring is not enough. But it's a psychologically fascinating phenomenon that I observe time and again. Firefighters and other experts see us working and say: Ah, now you from THW are here and measuring, so everything is safe! Of course, that's not the case. Extensive understanding beyond just measurements is needed for adequate safety. So, our task's primary focus is to swiftly find effective solutions that promote safety in an interdisciplinary way.

Q: What is your area of responsibility?

As a THW technical advisor, I am often en route to communicate and network with the THW on various fronts and engage with crisis teams. I also assist local authorities on-site, during operations, including the fire department or police, when necessary. This work is made possible with support from my community, my family, and employer. Our local branch in Weingarten attends an average of 24 operations annually.

Q: How are you summoned?

Calls come from the fire department or other authoritative figures like the officer in charge of an operation, the police, or an institution responsible for disaster prevention. Alerts are dispatched digitally through radio message receivers via Bodensee-Oberschwaben's integrated control center.

Q: Do you use measurement tools yourself?

Yes, with approximately two and a half thousand hours of practical surveying experience under my belt, I've done a substantial amount of training. Our current capabilities wouldn't have been possible without the continuous assistance of Leica Geosystems, particularly the support from Andreas Schulze, Heiner Gillessen, and Marcus Eichholz. The absence of support and backup would hinder our work. Among the valuable advice we received is the introduction of a calibration point as a fixed parameter for validating measurement data.

Leica Multistation MS50 monitoring post-fire scene and safety of emergency operation in Augsburg 2021

Q: How do you manage your work as a "lay surveyor"?

Leica's user-friendly software provides a significant advantage. Nonetheless, interpreting the measurement data can pose challenges for non-surveyors. Refraction, for instance, can create difficulties when measurements are taken over a hot surface or after a fire in an underground parking lot filled with soot particles in the air.

Q: What equipment do you use?

We employ tools such as the Leica MS50, the Leica Nova MS60 Multistation and the Leica Disto D8. These devices are compatible and allow for precise measurements and complex data capture, capabilities seen with the multistation. The multistation device, which combines a total station and a laser scanner, enables us to gather abundant information rapidly. Laser scanning has also made otherwise challenging tasks more approachable and quicker to execute while offering increased safety and convenience.

Leica Nova Multistation MS60 - THW

«To be able to assess hazardous situations correctly, 
we must be able to measure and capture complex structures to measure and capture.»


Q: What makes Leica's Multistation an attractive tool for you?

Effective evaluation of hazardous situations needs rapid and comprehensive data collection, and the ability to measure and depict complex structures. The Multistation, which merges a total station and a laser scanner into one, facilitates this. Traditional total stations only provide limited information and fall short when one needs a more comprehensive understanding of an object. However, laser scanning enables the THW to perform tasks more efficiently than before. For instance, we can survey a precarious building from a safe location on the ground within minutes while ensuring high accuracy. The safety this provides, coupled with the ability to view scanned point cloud data on-site via the Leica Captivate software, adds substantial value. This allows the team to ensure all required data has been captured before they retreat to the operations center or office for data processing, a task there's usually little time for during operations. The adaptability the Multistation provides during operations is also especially critical to THW's work.

Q: In which hazardous situations does the THW use the multistation?

Today, the multistation is indispensable for the THW and is used in all kinds of hazardous operations.

THW - Leica Multistation MS50 used in hazardous situation to safe lives


This includes fires, explosions and all other crises where there is an acute risk of collapse, such as damaged bridges or industrial plants. However, we also use the ESS in the event of an imminent collapse of excavation pits or landslides. During a landslide monitoring project, a resident once told us: "Since you've been here and taking measurements, I've been able to sleep peacefully for the first time in months.

Q: What did you use to measure before the Multistation?

With the Leica Disto D8 laser distance meter. We used it for the first time in 2012 when an old listed building in Bad Waldsee caught on fire. We monitored the building with the Disto D8, as the free-standing roof was in danger of collapsing. We were manually triggering the Disto D8 - click, click, click - while trying to capture the gable to protect our colleagues. When the Multistation came onto the market, it was a quantum leap.

Q: What event do you particularly remember from all those years at THW?

The underground garage fire in Ravensburg in 2014 was one of the most exciting operations.

We used the ESS for the first time in this incident. A vehicle had driven into the second basement of the underground garage and spontaneously ignited. The question quickly arose about how the high fire temperature of 800 to 1,000 degrees would affect the remaining structure of the underground garage with other vehicles. We then used the cooling phase for measurements with the ESS to assess the stability of the underground car park with construction consultants from the THW and fire department. 

Q: Has the Multistation ever let you down?

Never. The device's robustness was tested in the underground garage fire and many other cases. We work in environments with soot, water, wind, high plus and minus temperatures and external weather conditions. The device must always work in every situation, and it does! It does so 100% of the time. The system has never let us down.

THW - Leica multistation-never-let-me-down


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About the person Kevin Kärcher


THW OV Weingarten - Kevin Kärcher im Interview with Leica Public Safety

Since 1998, Kevin Kärcher has been serving as a volunteer technical advisor at the Weingarten branch of the German Federal Agency for Technical Relief (THW) in Baden-Württemberg. In his professional capacity, he works at Schuler Pressen GmbH, the largest press and forming manufacturer globally, boasting over 5,000 employees. As the Head of Engineering at Schuler Pressen, Kärcher oversees the Mechanical, Electrical, and Real-Time departments. Concurrently, he serves as a lecturer at Ravensburg-Weingarten University of Applied Sciences, specializing in forming technology and forming machines. The 45-year-old Kärcher resides near Weingarten with his family.



About the THW

THW logo - Leica Public Safety

The Federal Agency for Technical Relief (THW) operates under the Federal Ministry of the Interior and serves as the federal government's emergency response body. Known for delivering technical aid to those in need for over seven decades, the THW's structure is unique in its reliance on volunteer involvement, with 98% of its workforce being volunteers. It is composed of approximately 88,000 volunteer members who are distributed across 668 local associations nationwide, supported by over 2,100 full-time employees.

The synergy between volunteer and full-time roles is key to the THW's operations. Volunteers are frontline responders who perform rescue work, general repairs, organization, and emergency and humanitarian relief following significant natural disasters, both domestically and internationally. Full-time employees, on the other hand, are responsible for planning, crafting, and executing various products, services, and guidelines that drive the organization's initiatives.


Author:Manuel Huber

Editor: Malgorzata Krol
Global Director Marketing Communications - Public Safety & Forensics
Hexagon Geosystems


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