Anotace:
Terrain experiments for avalanche survival research require appropriate snow conditions, which may not be available year round. To prepare these experiments and test the protocol, it might be advantageous to test them in a laboratory with a snow model. The aim of the study was to find a material that can be used to simulate avalanche snow for studying gas exchange of a person covered with avalanche snow. Three loose porous materials (perlite, wood shavings and polystyrene) were tested in two forms—dry and moisturized. Each volunteer underwent six phases of the experiment in random order (three materials each dry or moisturized) during experimental breathing into the tested materials. Physiological parameters and fractions of oxygen and carbon dioxide in the airways were recorded continuously. All the materials selected as possible models of the avalanche snow negatively affected gas exchange during the breathing of the volunteers in a very similar extent. The time courses of the recorded parameters were very similar and were bordered from one side by the wet perlite and from the other side by the dry perlite. Therefore, other tested materials may be substituted with perlite with and appropriate water content. From all the tested materials, perlite is the best to simulate avalanche snow because of its homogeneity, reproducibility and easy manipulation.