Introduction

Extreme weather events currently observed on a global scale have been correlated with the current “climate crisis,” which, combined with population growth and urbanization, has exacerbated the consequences in terms of disaster casualties, property losses, and environmental impacts. The Search and Rescue project, among other related initiatives, has implemented part of the Disaster Risk and Resilience priorities outlined in the UN’s 2030 Sustainable Development Agenda. Its primary goal was to establish and promote a comprehensive framework encompassing system and equipment interoperability, training, and awareness by providing cutting-edge technologies and innovative tools for the first responders.

The technologies, tools, and techniques developed within the Search and Rescue project were successfully tested and validated through seven field exercises based on various use-case scenarios. Within this framework, a promising field technology—Membrane Inlet Mass Spectrometry (MIMS)—was adapted to meet the needs of first responders and tested for the first time in search and rescue operations with the “RESCUE-MIMS” prototype (TRL 6). Specifically, the device was used in relevant exercises and tested (a) as an early warning system on-board a ground robotic platform for first responders’ safety, and (b) as an “artificial sniffer” for detecting compounds related to human presence “human signs” according to literature, complementing the rescue dogs. The human chemical signs can be considered the total of the chemical compounds evolved by the human body and skin like axilla and sweat, as well as and the ones emitted via human breath [1, 2]. According to literature, the human body emits different types of VOCs like alcohols, aldehydes, amines, aromatics, ketones, etc. [3] while the majority of VOCs in breath may have concentrations ranging from ppb to ppt levels [4, 5].

In Table 7.1, the most representative VOCs and gases that have been correlated with human presence in literature are summarized that can be used for field analysis [6]; the characteristic mass fragments of those compounds are also provided for monitoring in Single Ion Monitoring (SIM) mode by using the RESCUE-MIMS prototype.

Table 7.1 Representative VOCs and gases that have been correlated with “human presence” in literature and their characteristic mass fragments for monitoring with mass spectrometry-based technologies [6]
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According to the literature, the above compounds may behave differently as they permeate the ruins of buildings, interacting with brick, concrete, wood, furnishings, and other materials [8].

Another important issue for the rescuers that operate in the disaster environment, as well as the canines, is the safety and security concerns arise. For example, in case of collapsed structures there is a possibility of toxic or explosive gases release due to destruction of pipelines or explosion of gas cylinders under pressure that might be under the ruins, or even fire spots that can be generated due to short circuits.

As a result of the above, it seems crucial to have field technologies capable of monitoring on-site and online such hazardous environments and at a safe distance from the source, in order to protect the firefighters or the first responders and their canines in general. However, chemical hazards’ release creates a strong chemical background under the ruins that may burden search and rescue operations of entrapped victims.

Methodology

As previously mentioned, mimicking the rescue dogs in the disaster scene is a complex issue since hundreds of chemical compounds with different origins can be present. In Fig. 7.1, testing of the RESCUE-MIMS in the field under the scenario “People Trapped Under the Rubbles” that took place in Limoges, France in cooperation with the PUI team (Pompiers de l’ Urgence Internationale), is shown.

Fig. 7.1
A set of 2 photos. The left one is of a rescuer entering a recess in a pile of debris. The right one is of the Rescue M I M S device placed amid the debris.

Testing of the RESCUE-MIMS in the field under the scenario “People Trapped Under the Rubbles” that took place in Limoges, France in cooperation with the PUI team

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Based on the scenario, the RESCUE-MIMS device was deployed in the field for measuring the compounds inside the voids of the collapsed structure and for providing a possible “alarm of a human” under the rubbles.

For the needs of the SnR project, a number of key compounds were selected for monitoring the exhaled air of individuals during preparatory lab-experiments, as well as for the field exercises, namely the aforementioned pilot “People trapped under rubbles.” These key compounds were monitored via their representative masses, based on the Table 7.1. More specifically, the selected masses for monitoring with the RESCUE-MIMS prototype were: mass 43 (acetone), mass 44 (carbon dioxide), mass 45 (ethanol), mass 58 (acetone).

The RESCUE-MIMS field technology has also been tested under the SnR project framework for remote sensing on-board robotic platforms under a simulated industrial fire scenario; forest fire expanded threatening an industrial zone.

In that scope, a number of chemical hazards for the safety of the first responders were selected at first place for initial testing and validation of the RESCUE-MIMS prototype in lab-scale. Specifically, the selected masses that were finally monitored with the RESCUE-MIMS prototype were: mass 17 (Ammonia), mass 28 (Carbon Monoxide), mass 30 (Nitrogen Oxide) mass 44 (Carbon Dioxide), mass 46 (Nitrogen Dioxide), mass 78 (Benzene) [9, 10]. The chemical data were transferred online and displayed as alarm messages on the SnR platform, informing the first responders at the command and control center.

As shown in Fig. 7.2, the robot was able to pass through the intense smoke and measure online the various airborne components, utilized as a screening tool of the toxicity of the area. Though, the thermal resistance of the materials of the whole equipment when using it in fire incidents needs to be considered to avoid any damage. Moreover, possible contamination of the detector due to smoke or tars should be taken into account; filters in front of the sampling probe can be used to protect it.

Fig. 7.2
A photo of the Rescue M I M S device in an open field with a dense dust and smoke cloud in the distance.

The RESCUE-MIMS on-board the SeekurJr robotic platform by DFKI was used as a remote early warning system of a hazardous smoky environment for the first responders

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Results

The RESCUE-MIMS was able to successfully detect online the increased intensities of masses that are correlated with compounds relevant to human exhaled air according to the literature, like Carbon Dioxide and Acetone, compared to the background measurements recorded inside the voids (See Figs. 7.1 and 7.3).

Fig. 7.3
A column chart plots the pressure in m bar versus scans. The approximate data are (40, 10 exponent negative 8.50), acetone (43, 10 exponent negative 9.5), and C O 2 (44, 10 exponent negative 8.7).

An indicative screenshot of the RESCUE-MIMS display while measuring inside the voids of the collapsed structure where the victim was entrapped (peaks attributed to acetone and carbon dioxide)

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The RESCUE-MIMS was also used in another use case inside the Search and Rescue project (forest fire expanded and threat an industrial zone), and tested as an early warning system on-board a ground robotic platform for the first responders’ safety; hazardous compounds, such as ammonia (NH3), carbon monoxide (CO), Benzene, were successfully monitored online and the respective alarms were sent to the SnR platform at the command and control center.

Specific Key Performance Indicators (KPIs) were used to evaluate the RESCUE-MIMS prototype in the aforementioned use cases; portability; robustness; easiness to operate; easiness to deploy; friendliness to the user; fast response times; high sensitivity; minimum false positives/negatives. Also, it has to be mentioned that in both use cases, usability testing of the Rescue MIMS prototype took place with the assistance of the end users. An important consideration when measuring online in the field is the potential background interferences that may create false positives or negatives; for this reason, background measurements were recorded by the RESCUE-MIMS in the respective pilots.

Conclusions

Based on the first responders’ feedback, it became apparent that it was possible to use a highly sensitive analytical technique in terms of ultra-low detection capabilities with minimum false alarms alongside sophisticated analytical equipment in the field. It is a promising field technology that can be used as a complementary tool to the classical detection options for location of entrapped victims under collapsed structures, in order to help the first responders in search and rescue operations, e.g., to cope with limitations when using rescue dogs in terms of availability, fatigue or incomplete/insufficient training. The RESCUE-MIMS technology has proven its effectiveness, but there is still room for improvement in terms of weight, ease of use, resistance to environmental, field conditions, and operating autonomy. Also, special training is needed by the users, e.g., one or two members from the firefighters team should be trained every 2–3 months, as already do for similar technologies, like the scanner or the drones.