Post-fire deformation monitoring with Leica Geosystems total stations in the Polish Fire Service.

Author: Malgorzata Krol

Unit- and public safety as a priority in every search and rescue operation

At first glance, talking about the day-to-day job of the Polish Fire Service, everything seems to be clear: firefighters put out fires. This is true but putting out fires is only one of many tasks of this professional, uniformed, well-trained, and specially equipped unit.

The Polish State Fire Service was established on July 1, 1992. Since then, the organisation and the functions of the units have entirely changed. Today, Polish firefighters do not only put out fires. Their tasks also include the following rescue actions: technical, chemical, ecological, medical etc. The firefighters also fight against natural disasters, rescue people injured during disasters, support the police units searching for missing persons in open terrain, and respond to other local threats, such as major traffic accidents.

The Polish State Fire Service comprises the National Headquarters of the State Fire Service, 16 Provincial Headquarters, 335 County / Municipal Headquarters. In Poland, there are 515 Fire and Rescue Units. The recruits are taught the skills of firefighting in five specialised schools in Poland. The Main School of Fire Service (Szkoła Główna Służby Pożarniczej) in Warsaw, the Central School of Fire Service in Częstochowa, the two Schools of Aspirants in Kraków and Poznań, and the Officers School of the State Fire Service in Bydgoszcz.

Specialized Search and Rescue Units

At the Provincial Headquarters of the State Fire Service in Katowice exists the Specialized Search and Rescue Group: The SGPR Jastrzębie-Zdrój, under the command of Senior Captain Paweł Krótki. This unit complies with the standard of "A", "B", and "C" levels of the so-called "operational readiness" following the "Principles of Search and Rescue in the National Rescue and Firefighting System". Additionally, some SGPR unit members are part of the USAR Poland unit, a Search and Rescue group also designed for international operations.

The Specialized Search and Rescue Group (SGPR) in Jastrzębie-Zdrój, as one of only a couple of firefighting units in Poland, maintains the highest level: "C" of operational readiness to carry out extreme challenging firefighting and rescue missions throughout the whole country. Those different readiness levels depend on the unit's suitability of emergency response, the number of firefighters, their qualifications, and the technical equipment in this unit.

The emergency response actions of the SGPR unit are also supported by rescue dogs and high-class equipment. For example, the location equipment, including a camera plus geophone and a deformation monitoring system based on two Leica Geosystems TS16 total stations. The Leica systems are used to continuously monitor the stability of damaged structures of burned buildings when buildings might collapse. In addition, the SGPR unit uses structural stabilisation equipment, height rescue equipment and a wide range of other technical equipment necessary in complex rescue operations.

Top-notch monitoring system supporting the emergency response in the SGPR

Since 2016, the SGPR Jastrzębie-Zdrój unit has been equipped with two Leica Geosystems Total Station systems for monitoring the stability of close-to-collapse burnt structures. For rescue purposes, deformation monitoring is one of the major tasks of this kind of operations. The stability of a building after a fire or a gas explosion can quickly change and usually poses a significant threat to the rescue units working on-site. Continuous monitoring of changes in the structure's condition or possible falling debris is necessary to maintain the safety of the firefighters, the emergency response units, the living victims and the success and efficiency of a rescue mission.

Source: SGPR Jastrzebie Zdroj

Each of Leica Geosystems's two systems includes a Leica TS16 robotic total station, a laptop computer with Leica GeoMoS monitoring software, a power box, and an optical and acoustic beacon. - "We acquired the first set based on the TS16 in 2016 and the second set in 2018. We still have a manual total station at our disposal, which we treat primarily as backup equipment. The manual total station is sometimes used in situations when it is necessary to observe a larger number of points from several positions" - explains Captain Paweł Krótki, the commander of SGPR Jastrzębie-Zdrój.

The SGPR firefighter- and rescue teams, especially the operators of Leica Geosystem's equipment, measure and monitor the stability of the destroyed or endangered structure in many fire- or explosion related incidents every year. They observe and monitor the condition of the buildings and make sure that the structural movements of walls, roofs etc. do not threaten the safety of the rescue operation.

How does the monitoring of endangered structural elements with total stations look like?

After extinguishing a fire and the initial securing of the scene, the SGPR unit commander and the total station operator make the first observations, the reconnaissance and the assessment of the situation to perform the monitoring activities securely. They pay attention to the size of the object, the extent of the area around the damaged building, the range of the used devices, the relative safety of the rescue units during the work on the scene and the possible preservation of the structural elements of the building. Then the positioning of the Leica Geosystems total station(s) is determined.

The monitoring of the object/building starts with identifying and selecting a certain number of distinctive points on the building structure. Those points need to be easily identifiable and characteristic. One total station continuously observes the defined points in predefined time intervals. Essential for the operation's success is that the monitoring activities must not, under any circumstances, impede the access of emergency units carrying out the direct rescue operation.

The observation, the measurement, and the monitoring of the pre-defined distinctive points in the affected structure take place throughout the whole operation. The Leica Geosystems TS16 total station TS16 does this autonomously and automatically. Provided, that the points to be monitored have been defined and programmed into the GeoMoS software first, to “instruct” the Leica Geosystems total station to measure them accordingly. The Leica Geosystems system is equipped with an alarm module, which reacts to changes in the position of the measured points and gives optical and audio feedback to the operator. Any point deviation from the original position is noticed and reported.

The threat of the so-called "secondary collapse" of a post-fire structure can be extremely dangerous. When a deviation is noticed, the total station operator informs the rescue unit commander about the change in the building condition. Based on that information, the commander instantly makes his decision about any further action. The decision might be about a temporary or even a complete stop of the rescue mission, or the withdrawal of units searching the rubble and securing the breached structure again. Usually, the decisions are made temporarily, allowing for resumption and safe completion of rescue action after re-securing the scene.

The safety of rescue teams and possible victims is paramount

Rescue operations on fire- or explosion scenes and during construction disasters are the most complicated, complex, and dangerous tasks carried out by the specialised Search and Rescue units of any firefighting unit. Clearing the disaster area in situations where there might be fire under the rubble, exposed power cables, or gas leakages are tasks only for these specially trained and equipped formations of any fire brigade. Securing the environment and the positive outcome of a rescue mission as well as making sure that the safety of the involved teams and possible still living victims is maintained, are the major tasks in the day-to-day job of the specialised firefighting forces.