(green circles): Rutschblock score 7, 6 or 5 with partial fracture and ECT with no fracture, no fracture propagation or only partial fracture propagation. Fair (orange circles): Rutschblock score 5 entire [...] individual elements are explained within the diagram below and in the text that follows. Rutschblock and ECT The rutschblock (RB) test is the most reliable indicator of stability. SLF observers perform this test [...] conduct one or two extended column tests (ECT). The detailed instructions for a rutschblock and ECT are in the next image. Rutschblock and ECT testing furnishes information on how easily a fracture was initiated
classes by danger level based on rutschblock test results. There are no data for danger level 5. In the Swiss Alps in the last twenty years, more than 4,000 rutschblock tests have been performed and, on [...] good rutschblock test results decreases sharply as the danger level increases. Fig. 2: Statistically simulated stability distributions illustrating the proportions of very poor and good rutschblock test [...] of snowpack stability in the field. Snowpack stability can be measured by testing, as with the rutschblock test , or with an instrument, such as the SnowMicroPen . Performing measurements in numerous places
resistance as the probe is driven into the snow by a motor (photo: Jürg Schweizer/SLF). Figure 4: The rutschblock test is the mother of all snowpack tests. It resolves several questions: whether or not the snowpack [...] from underneath and, among other things, records the penetration of melt water into the snowpack. Rutschblock test as the mother of stability tests In the 1980s more direct methods of examining snowpack stability [...] in the field were developed. Initially serving only to demonstrate a miniature snow slab, the rutschblock test emerged as the standard technique. First, the four vertical faces of a block of snow measuring
at set measuring sites and also some 40 slope profiles , using for example stability tests ( 'Rutschblock' tests ) on representative test slopes. The most recent profiles are made available to the public