Backcountry Skiing Core Glossary

AT is an abbreviation used in relation to backcountry skiing which stands for "alpine touring," meaning the use of skis similar to alpine (ski resort) skis, and bindings that unlatch at the heel to provide a walking gait, and latch down at the heel to provide a fixed heel for alpine skiing. Article about AT randonnee skiing.

There are two major families of backcountry ski equipment. One family ("AT" "randonnee") uses bindings that free your heel for vertical movement during walking, then let you latch the heel to your ski for downhill skiing. The other clan is "telemark" gear (see below) that always has a free heel, uphill or down.

The downhill latched heel family of backcountry skiing gear used to be known as "alpine touring," because the free-heel walking/climbing mode was the "touring" mode, and the latched heel mode was the "alpine" mode.

Around 1990, when Lou Dawson began writing about "alpine touring" gear for Couloir Magazine, he and and a few other people (namely, binding inventor Paul Ramer) often shortened the term "alpine touring" to the abbreviation "AT." While the abbreviation caught on to some extent, it is not hip or descriptive (it’s often mistaken to mean "all terrain"), so other terms have gained favor. In particular, the term "randonnee" (see below).

Avalanche, when used regarding backcountry skiing, means a snow avalanche. This mountain hazard kills more backcountry skiers than any other danger. Much energy in the community is devoted to avoiding avalanches as well as having the skill and knowledge to perform companion rescue (see below). Challenge is that many snow avalanche victims die from trauma as being caught in an avalanche is similar to falling down a mountain. Thus, avalanche avoidance is extremely important.

Backcountry Skiing is skiing untamed snow in sparsely populated, usually mountainous, generally undeveloped areas. Human power is the usual means of travel and ascent. If mechanized ascent is used extensively one might say, for example, they are "helicopter skiing in the backcountry," but stating they are "backcountry skiing" would not be correct in the spirit of present day use of the term. Use of mechanized access such as helicopter or snowmobile transport to a remote camp or hut may also occur in backcountry skiing, but such mechanized use is intended for access to an area, rather than a substitute for muscle power in gaining vertical with the intent of skiing back down.

Discuss the definition of "backcountry."

Companion Rescue is a term used in backcountry skiing to talk about snow avalanche rescue done by party members rather than an outside rescue group. This is an important concept, as a buried avalanche victim only has minutes before they begin to suffocate (provided they are not killed by likely trauma), and thus companion rescue is the only possible way to save their life. Companion rescue is done with essential equipment: avalanche beacon, shovel, and probe. Effective companion rescue also requires first aid skills, solid judgment and good teamwork.

Delta is usually used to describe the angle created by the ski binding toe being lower than or equal to the heel. A binding that holds the boot at the same height at toe and heel would be said to have “zero delta.” Binding delta combines with boot “ramp” inside the boot to create your “combined ramp angle” or “combined delta.” See “ramp” below.

DIN is an acronym for Deutsche Institut fuer Normung, The German standardization institute. Among other things this body acts as an organizer for many ski gear standards, such as the thickness of boot soles, binding setting numbers, and much more. While DIN is a German organization, it long ago became the traditional standardization source for many ski equipment standards, including how binding safety release settings are calibrated, hence the terms "DIN setting" or "DIN number" regarding ski binding setting. Our DIN chart is here.

DIN is similar to ANSI of the United States which is the official U.S. representative to the International Organization for Standardization (ISO). A DIN standard is the “norm” that’s then tested for TUV certification of ski gear such as bindings.

How the different standards and certification organizations (DIN, ANSI, ISO, TUV) relate to each other is difficult to clarify, main concept is that standards tend to be created and managed by organizations such as DIN, yet products that portend to adhere to the standard are certified by organizations such as TUV. This is why you’ll see some ski bindings imprinted with the letters "TUV."

Extreme Skiing traditionally described skiing steep terrain where a fall would result in death or at least certain injury. In the traditional sense, it was a branch of mountaineering, and frequently done in conjunction with climbing a peak. The genre originated in the Alps, especially in Chamonix, France. The term was co opted by the North American ski film industry in the 1980s to describe skiing with an aggressive style on difficult terrain, frequently in ways design to look good for photographs or movies, with numerous drops off cliffs. The latter style evolved and is now known as “freeride,” and the term “extreme” skiing appears to have nearly totally reverted back to its original definition.

Freeride skiing is a relatively new term that’s used to describe attitude and overall style as much as ski technique. A freeride skier embraces nearly all aspects of skiing, with emphasis on faster more fluid technique, as well as frequent forays into the backcountry. Freeride skiers also include tricks in their repertoire, or at least aspire to. Freeride tends to be a youth culture adjunct, with associated clothing styles, though the term has become mainstreamed and is frequently used to describe the market segment of more athletic and adventure oriented skiers of any age. Freeride skis are usually designed for fast aggressive skiing in varied conditions, with emphasis on natural snow.

Mondo boot sizing is basically the measurement of footwear length in centimeters, the "metric" system, if you will. Chart below gives you conversions, remember footwear has no hard standards when it comes to fit, so try before you buy or be ready to do a few returns if you’re purchasing via mail order.

U.K

Euro
Mondo Size
U.S.Men’s

U.S. Wmn’s
3

35

21.5
-
4.5

3.5
35.5

22

-
5
4
36
22.5

4.5

5.5
4.5
37
23
5

6

5

37.5
23.5
5.5
6.5
5.5
38

24
6
7
6
39
24.5

6.5
7.5

6.5

40
25
7

8
7

40.5

25.5
7.5
8.5

7.5
41

26

8
9
8
42
26.5

8.5

9.5
8.5
43
27
9

10

9

43.5
27.5
9.5
10.5
9.5
44

28
10
11
10
44.5
28.5

10.5
11.5

10.5

45
29
11

12
11

45.5

29.5
11.5
12.5

11.5
46

30

12
-
12
47
30.5

12.5

-
12.5
48
31
13

-

13

50
31.5
13.5
-
13.5
-

32
14
-

Randonnee is a French word used by English speakers to describe the gear or technique used for "AT" alpine touring skiing (see above). The word actually means "excursion" or "tour," and if used in French to speak of ski touring is generally combined with the word "ski" as it otherwise could mean anything from a walking tour to a motorcycle tour. The spelling of the word is frequently mangled. The totally correct way to write it is with an apostrophe as randonnée, but it’s frequently spelled as rando, randonee or randonne. Here at WildSnow.com we tend to use the none apostrophe spelling for convenience sake.

Pebax® is a plastic commonly used in ski boots. It offers the widest range of performance (mechanical, chemical, processing) among the thermoplastic elastomers. It is very lightweight, and is not as influenced as much by temperature as other commonly used ski boot materials, such as polyurethane (which gets quite a bit stiffer as it chills). The word "Pebax" stands for polyether block amide. For info about mold and melt temperature of ski boot Pebax, check here.

Boot fitters should note that Pebax has a shrink rate of 0.5 to 1.5%, and does have a memory if boot punching is not done with enough heat and pressure. One trick used by WildSnow.com is to pre-heat our aluminum boot expander mandrels to around 260 degrees F, checked with an infrared thermometer. Test on throw-away boots.

Also, check this link on the Pebax website.

Ramp Angle is a term most often used to describe the for/aft angle of the ski boot surface under the user’s foot. The surface under your foot inside the boot is termed the “boot board” or “zeppa.” Most often the toe of the boot board is lower than the heel, creating “positive ramp angle.” When this sort of angle is created by the ski binding, it is usually termed “delta.”

The term tech when applied to ski bindings refers to bindings based on the system originated by Fritz Barthel in Austria and mainstreamed by Dynafit during the 1980s. The system uses boots with factory installed toe and heel fittings (sockets) that elminate the need for a “plate” or “frame” that connects binding toe and heel during ski touring operation when the walking stride must lift the heel off the ski. The original Dynafit bindings were known as “Low Tech,” and “Tour Lite Tech, TLT”) which led in turn to the term “tech” as a name for any binding using this type of operation and construction.

Telemark skiing is a style of skiing in which the heel is allowed to move upward at all times, and the "telemark" turn is frequently used. Telemark turns resemble a dance "genuflect" or what some term a "split stride." Telemark skiing is useful for backcountry skiing but is not essential since "AT" (see above) alpine touring equipment provides the same functionality for climbing, and is effective for downhill as well.

Titanal® is an aluminum alloy similar to other high quality aluminum alloys, only it is one of the highest strength of the lot. Despite its name, Titanal contains no titanium, but rather a portion of zinc and other metals, some of which other aluminum alloys use as well. Titanal is an excellent material for the structural component of sporting goods such as skis and ski bindings. Titanal is sometimes confused as titanium, or misleadingly marketed as such.

Welcome to Louis (Lou) Dawson's backcountry skiing information opinion website and e magazine. Lou's passion for the past 45 years has been alpinism, climbing, mountaineering and skiing -- along with all manner of outdoor recreation. He has authored numerous books and articles about backcountry skiing and is well known as the first person to ski down all 54 of Colorado's 14,000-foot peaks, otherwise known as the Fourteeners! Books and free back country news and information here, and tons of Randonnee rando telemark info.

All material on this website online magazine is copyrighted, the name WildSnow is trademarked.. Permission required for reproduction, electronic or otherwise. This includes publication and display on other websites by whatever means. PLEASE SEE OUR COPYRIGHT and TRADEMARK INFORMATION.

Backcountry skiing is a dangerous sport. You may be killed or severely injured if you do any form of ski mountaineering, skimo randonnee and randonnée skiing. The information and news on this website is intended only as general information. While the authors and editors of the information on this website make every effort to present useful information about ski mountaineering, due to human error the information, text and images contained within this website may be inaccurate, false, or out-of-date. By using, reading or viewing the information provided on this website, you agree to absolve the owners of Wild Snow as well as content contributors of any liability for injuries or losses incurred while using such information. Furthermore, you agree to use any of this website's information, maps, photos, or binding mounting instructions or templates at your own risk, and waive Wild Snow its owners and contributors of any liability for use of said items for backcountry skiing or any other use.

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