Survival chance optimized search strip width in avalanche rescue

When using transceivers (or avalanche beacons) to search for fully buried subjects, the search strategy depends on the signal search strip width which influences the search time until the first signal from the buried subjects can be received by the rescuer. The signal search strip width depends on technical characteristics of the avalanche rescue devices, the avalanche scenario as well as the rescuer's behavior. The larger the signal search strip width, the shorter is the search time and therefore the higher the survival chance of the buried subject. However, if the search strip width chosen is too large, the probability to miss a buried subject increases, which makes time-consuming multiple searches necessary — and decreases survival chances. Therefore, the search strip width needs to be optimized. We developed a simulation approach for the optimization of the search strip width which allows considering the many factors that affect the search and making realistic (rather than worst case) assumptions for their values. Our results suggest that the optimal signal search strip width is higher than previously assumed, that is – depending on the type of transceiver – about 1.2 to 1.4 times the realistic maximum range. In future applications, the simulation may be used to optimize a broad variety of search parameters or even entire search systems.