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Interpretation guide to avalanche bulletin

The WSL Institute for Snow and Avalanche Research SLF has been publishing avalanche bulletins since 1945. The Interpretation Guide was first published in 1985. It describes the avalanche bulletin and additional products, and seeks to help the user interpret their contents. Changes were incorporated in later editions (1993, 1994, 1998, 1999, 2001, 2002, 2003, 2004, 2007, 2008) to reflect both new formats and publication times for the avalanche bulletin and the availability of various supporting products. The preceding, thoroughly revised 2012 edition was issued in connection with a fundamental overhaul of the avalanche bulletin. Only minor amendments were made in the current 2015 edition.
The basis of all the avalanche warnings issued by the SLF is the standardised avalanche danger scale with five danger levels, which has been in use throughout Europe since the winter of 1993/94. This scale, with minor deviations, is also acknowledged as the norm overseas, in particular in Canada and the U.S.
The Interpretation Guide does not encompass the information platforms for the safety services, such as the GIN (common natural hazard information platform) and the IFKIS-InfoManager (inter-cantonal early warning and crisis information system), or the special products they contain which are not intended for the general public.
The users of these platforms receive training by attending courses for safety authorities at the SLF. The binding version of the Interpretation Guide is always the most recently revised edition, which is made available on the website of the SLF at
The descriptive terms for persons, job titles and professions in this Interpretation Guide refer to both sexes unless otherwise indicated by the text.
The term "skier" in the context of avalanches, as in "skier(-triggered) avalanche", is widely used to refer not only to skiers, but to all those who engage in snow sports, including snowboarders, snowshoe hikers and others. It is used in this way in the Interpretation Guide as well.

Interpretation guide PDF (3 MB)

Glossary snow and avalanches