Easy and Portable
After natural disasters – especially earthquakes – it is very important to quickly find under the rubble of the survivors. Because every second count after buildings collapses from an earthquake, bombing or other disaster is to rescue people who could be trapped in the blockage/fire. But finding entrapped humans among the blockage can be challenging or even impossible.
A team of researchers from the Swiss Higher Technical School (ETH, Zurich), under the guidance of Professor Pratsinis, developed a simple, inexpensive device that will help in the search for surviving victims of the disaster.
Scientists now report on April 18, 2018, in American Chemical Society Journal for the development of an inexpensive, selective sensor that is light and portable enough for first responders to hold in their hands or for drones to carry on a search for survivors.
The first step after buildings collapse from an earthquake, bombing or other disaster is to rescue people who could be trapped in the rubble. But finding entrapped humans among the ruins can be challenging. Scientists now report the development of an inexpensive, selective sensor that is light and portable enough for first responders to hold in their hands or for drones to carry on a search for survivors. “Professor Pratsinis”
During a rescue, the survival rate of victims stuck in the rubble rapidly drops, so it’s critical to get in there fast (safely, if possible, but who can guarantee?). Current approaches include the use of sniffing dogs and acoustic probes that actually detect human voice for help. But these methods have lots of drawbacks, such as the limited availability of canines and the silence of unconscious victims. Therefore, a technology that quantitatively to detect human chemical characteristics, which includes molecules that are exhaled or that waft off the skin, are promising. But so far, these devices are too bulky and expensive for wide implementation, and they can miss signals that are present at low concentrations. So, Sotiris E. Pratsinis and colleagues wanted to develop an affordable, compact sensor array to detect even the most critical signs of life.
Currently, for such searches, rescuers use specially trained dogs or acoustic probes. However, the number of dogs is limited, and they are not always available, and probes are useless when it comes to unconscious people. There are also systems that react to chemicals released by humans, but they are very expensive and very cumbersome.
The device with five sensors, developed in Switzerland, is very compact – so much that it fits in your hand and is easily installed on a drone. Three sensors are responsible for the detection of specific chemicals that are exhaled by the victims, or released through the skin – acetone, ammonia, and isoprene. Two other sensors fix the humidity level and CO2 , which are also markers of close human presence.
When conducting laboratory tests, participants were placed in plethysmographic chambers (plethysmography is a process of detecting the size and volume of any part of the human body and organism) to simulate a blockage. The sensor array was able to fix the above-mentioned chemicals at a concentration of three per billion, which is unprecedented for a portable detector.
Now scientists plan to transfer the tests from the laboratory to the zones of real natural disasters.