Molecules in their breath, sweat and skin have been used to detect humans in a simulation of a collapsed building, raising the prospect of portable sensors for use in real-life situations, such as the devastating aftermath of the 9/11 attacks and more recent disasters in New Zealand and Japan.
Published today, Monday 12 September, in IOP Publishing's Journal of Breath Research, the study examined flumes of air to create a preliminary profile of molecules that could indicate human activity in a disaster zone, and it is notable for being the first of its kind to use human participants.
Over five days, in six-hour intervals, eight participants entered a simulator of a collapsed glass-clad reinforced-concrete building, which was designed, built and tested by the researchers from Loughborough University, National Technical University of Athens, University of Babe-Bolyai and University of Dortmund.
A variety of sensors, positioned throughout the simulator, rapidly detected carbon dioxide (CO2) and ammonia (NH3) with high-sensitivity in the plumes of air that travelled through the constructed rubble, highlighting their effectiveness as potential indicators.
In addition to these molecules, a large number of volatile organic compounds were detected; acetone and isoprene being the most prominent potential markers.
Interestingly, there was a marked decrease in NH3 levels when the participants were asleep; a finding the researchers could not explain and will investigate further, along with the build-up of acetone with increasing food withdrawal and the presence of detectable molecules in urine.
When trapped within a void of a collapsed building, casualties release volatile metabolites -- products of the body's natural breakdown mechanisms -- through their breath, skin and other bodily fluids, which can have complicated interactions with the building materials. Furthermore, these interactions change with conditio
|Contact: Michael Bishop|
Institute of Physics