Crevasses cause what percentage of all fatal accidents on glaciers, world wide? 
( ie. total glacier fatality rate, and the number caused by crevasses,
per annum world wide).

Crevasses

Travel on glaciers ? common in many parts of the Alps and North
America ? exposes you to the danger of crevasses. Formed when
pressures on a glacier cause the smooth flow of ice to break up,
crevasses are vertical slits in the ice from one to twenty metres wide
and the worst can be up to several hundred metres deep. Sometimes
?open? and clearly visible, sometime ?covered? and invisible on an
apparently smooth snow field. Falling into a crevasse transforms a
comfortable horizontal world into a terrifying vertical ice cave and
kills victims through the trauma of the fall, or the onset of
hypothermia if a timely extraction cannot be effected.


Ranking The Risks

Rescue professionals will tell you that accidents can have multiple
causes: the onset of bad weather, fatigue or lack of experience
amongst the party, simple errors in navigation and so on. Sometimes a
combination of otherwise small problems (late start, equipment
trouble, minor errors in navigation, worsening weather) can build up
to produce a potentially dangerous situation. The technical term is
?incident spiral? as small incidents compound each other to produce a
potential tragedy.

That said, it may be helpful to get a sense of the relative level of
each risk. To do this, we have analysed statistics on the recorded
causes of death in fatal accidents in the Europe and North America. On
average, over the past 20-30 years, more than 300 people have been
killed off-piste each winter, with over 150 of those deaths occurring
in the European Alps.

Hard statistics on causes are tricky to come by, and this is by no
means definitive, but the conclusion of our analysis is pretty clear:

    * Avalanche: around half of all fatalities,
    * Falling on steep ground: a further one in four,
    * Cold injury: one in six,
    * Getting lost: one in ten, and
    * Crevasse fall: the final one in twenty.
http://www.planetfear.com/article_detail.asp?a_id=357
........hope this answers (partly) your question............

Anne-Marie

this question seems somewhat like "a mission impossible" to me.............

There are many reasons why we have no rules or real guidelines in ski
mountaineering:the complexity of the situation; a lack of knowledge of
hidden risks and real risks, or because we have no real statistics to
prove right or wrong. Therefore, we have to ask ourselves over and
over again if we are doing the right thing to prevent a crevasse fall.
Even by preparing for every possible hazard and risk, we will never be
able to minimize risk 100%.

http://www.amga.com/about/enews/e_news_april.html

perhaps asking this question "per country" might give you somewhat of
an idea.......

PDF] Off-Piste and Backcountry Ski Accidents in France for 2003-2004
File Format: PDF/Adobe Acrobat - View as HTML
Page 1. Page 1 of 19 An Analysis of Off-Piste and Backcountry
Accidents in ... The reported
altitude of avalanche accidents was plotted as a polynomial trend line. ...
mapage.noos.fr/pistehors/ images/avalanche/analysis-2004.pdf - Similar pages

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