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History of the SLF

Swiss Federal Commission for Snow and Avalanche Research founded in Bern.
1935/36 First snow experiments conducted in a house built of blocks of solid snow in Davos Platz.
1936 Construction of the first snow laboratory at 2662 m on the Weissfluhjoch above Davos in order to allow longer-term observations and experiments to take place. The Parsennbahn railway operator made available a wooden barrack house and a workroom in the valley station. The house is buried underneath snow every winter and thus serves as a natural cold laboratory with a constant temperature of -5 to -7° C.
1942 Foundation of the Institute for Snow and Avalanche Research, Davos-Weissfluhjoch, and construction of its first home on the Weissfluhjoch. The principal fields of research remain the development of the snowpack, snow mechanics and avalanche formation, and the crystalline structure and metamorphosis of snow.
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  Inaugural snow experiments took place in the snow block house in Davos Platz in 1935/36. In 1936 a wooden barrack house on the Weissfluhjoch served as a snow laboratory.
1944 Commissioning of the first cold laboratories.
1945 Transfer of responsibility for avalanche warnings from the Swiss Army. Between 1946 and 1950, establishment of a civilian avalanche warning service with 20 observation stations. One regular avalanche bulletin a week was broadcast on radio and television for the emerging winter tourism industry.
1950 Prof. Marcel de Quervain succeeds Dr. Edwin Bucher as head of the institute.
1950/51 The extreme winter of 1950/51 claims 98 victims in Switzerland and heralds fundamental change. The catastrophic events call for action in the form of both basic research and practical support with shoring techniques and the avalanche warning service. Collaboration with the Swiss Meteorological Office (SMA) is stepped up to further increase the reliability of the avalanche bulletin.
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  The extreme winter of 1950/51 claimed numerous victims (Vals, 1950/51). Afforestation project in an avalanche starting zone at the Stillberg test site.
1953 With the forest emerging as a key form of long-term avalanche protection, cooperation is established with the WSL, the Swiss Federal Institute for Forest, Snow and Landscape Research (then the EAFV) in Birmensdorf. Long-running joint projects are launched, including the Stillberg test site in the Dischma valley to investigate afforestation in an avalanche starting zone near the tree line.
1955 Adolf Voellmy, a scientist at EMPA, the Swiss Federal Laboratories for Materials Testing and Research, introduces the SLF to a treatise that allows the calculation of avalanches' runout distances and dynamic compression forces  It provides a fundamental basis for designing barriers (deflection structures, snow sheds) in the track of an avalanche and for demarcating avalanche danger zones in settlements.
1956 Construction of the snow chute alongside the institute to facilitate the practical study of dynamic processes. Experiments with the snow chute illuminate the flow behaviour of snow over short distances, the compression forces that arise upon collision with rigid obstacles, and the retardation effect of flexible obstacles.
1961 The SLF produces the first avalanche zone plan for the community of Wengen.
1965 First test of avalanche transceivers conducted at the SLF.
1968 The extreme winter of 1968 affects Davos especially severely. The institute is cut off for three weeks.
1972 The effects of explosions on the snowpack are examined. The analyses give rise to the publication of practical guidelines for triggering avalanches artificially.
1973 Start of investigations into quantitative avalanche forecasting and snowpack development on slopes (Gaudergrat test site).
1980 Prof. Claude Jaccard takes over from Prof. Marcel de Quervain as head of the institute.
1983 First measurements of avalanche speed are taken in the Lukmanier region.
1986 The SLF celebrates 50 years of snow and avalanche research on the Weissfluhjoch.
1989 The SLF becomes part of the WSL, the Swiss Federal Institute for Forest, Snow and Landscape Research. Since the amalgamation, the SLF has belonged to the domain of the ETH (Swiss Federal Institutes of Technology).
1992 Prof. Dr. Claude Jaccard hands over leadership of the institute to Dr. Walter Ammann.
1993 The international working group of the European avalanche warning services sets a landmark. For the first time, representatives of the European alpine countries agree on a uniform definition of the avalanche danger levels. The five-point European Avalanche Hazard Scale is born.
1995 The SLF opens a branch station in Sion to provide a more immediate response to the issues affecting the canton of Valais.
1996 At the end of November 1996, after 60 years of snow and avalanche research on the Weissfluhjoch, the institute's new building on Flüelastrasse in Davos Dorf becomes the headquarters of the SLF. The institute's former main building on the Weissfluhjoch remains at its disposal for research purposes. It can also be used to accommodate groups taking part in business events, workshops, information sharing and altitude training.
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  The building of the SLF Institute in Davos Dorf. Weather station of the Intercantonal Measurement and Information System (IMIS).
2004 Expansion of the SLF's activities focuses more acutely on other natural hazards. In conjunction with Birmensdorf, the modelling of dynamic process is extended to embrace debris flows. At the same time, the development of warning and information systems for hydrological natural hazards in alpine valleys (torrents and debris flows) is initiated within the framework of pilot projects.
2006/07 The natural hazards research unit and its two sister units in the WSL, forestry and landscape, are dissolved in a restructuring exercise. The new organisation encompasses 16 research units. Dr. Walter Ammann is appointed deputy director of the WSL and later chairman of the International Disaster Reduction Conference (IDRC). Dr. Jakob Rhyner is appointed director of the Davos facility.
 2008 The SLF adopts its new identity as a branch of the WSL Institute for Snow and Avalanche Research.
 2012 To coincide with the start of the 2012/13 winter season, the SLF has thoroughly revised the avalanche bulletin format. The principal new aspects are: two assessments a day (8 am and 5 pm) covering all regions in four languages, and a zoomable interactive danger map. For the first time, the description of the avalanche danger is being compiled from a catalogue of standard phrases and produced simultaneously in all the languages. The avalanche bulletin has been optimised for the internet and smartphones.