Grades versus difficulty

It is important to keep in mind the difference between grades and actual difficulty. Grades give a relative indication of the requirements of a route or itinerary, under normal conditions. Actual difficulties are of course highly dependent on the conditions (weather, ice…) as well as on the fitness and technical abilities of the party. Unlike a grade, which is constant for a given itinerary, difficulties can thus change considerably from one day to the next.

Never ending discussions on the relative merits of grading systems are a characteristic of mountaineering (including on the forums of camptocamp). Several grading systems were created just for ski-touring and ski-mountaineering. Some of these have gained a broad following while others have disappeared from usage. In addition, different countries or regions tend to use different grading systems.
In the camptocamp guidebook, two systems are used:

Alpine grade

Made popular by François Labande through his guidebooks, the grading system offers two different grades: a global grade which describes the overall difficulties of the itinerary (using the same logic as the global alpine climbing grade) and a descent grade which describes the most difficult stretch of downhill skiing on the itinerary.

Global grade

The global grade offers an overall estimation of the difficulties of an itinerary and how sustained they are, as well as altitude and the normal duration of the itinerary. The grade uses the same letter coding as the global alpine climbing grade but they do not overlap (see warning below).

F: Easy (facile)
PD: Slightly difficult (Peu Difficile)
AD: Somewhat difficult (Assez difficile)
D: Difficult
TD: Very difficult (Très Difficile)
ED: Extremely difficult (Extrêmement difficile)
EDx: Extremely difficult extended : ED4, ED5, ED6, ED7...
Grades are nuanced using + (harder) or - (easier).

Warning: The global grade for skiing is for skiing, not for mountaineering. A snow couloir can easily be graded D for skiing while it’s mountaineering grade would not exceed PD or AD.

Descent grade

This grade gives additional information to that provided by the global grade It evaluates the difficulty of the most difficult stretch of downhill skiing on the itinerary. It is essentially related to the slope but also takes into account exposure. It is split into the following grades:

S1 : easy descent which does not require any particular technical abilities such as forest tracks for example.
S2 : Wide slopes which are easy to manoeuvre, maybe fairly steep (25°).
S3 : Slopes up to 35° (equivalent to the steepest runs in ski resorts, on hard snow). Requires good skiing abilities in all snow conditions.
S4 : Slopes up to 45°, if exposure is low (between 30 and 40° if it is high or the passage is narrow). Very good skiing abilities are required.
S5 : Slopes between 45 and 50° or more if exposure remains low. From 40° upwards if exposure is high. As well as a perfect downhill skiing technique, control of nerves becomes very important at this level of difficulty.
S6 : Above 50° if exposure is high (which is often the case) or short stretches above 55° with little exposure.
S7 : Stretches at 60° or more, high rock bands to jump or more generally very steep or exposed terrain.

Toponeige grading system

Made popular by Volodia Shahshahani, the grading system includes three grades: a technical downhill (skiing) grade, an up-hill grade (not used on camptocamp) and an exposure grade.

Technical skiing grade for the downhill portion of the itinerary

The grade includes 5 levels. The first four have three subdivisions (for example 2.3 or 3.1) and the fifth level is open-ended.

Ski 1. Initiation. Slopes do not exceed 30° with no narrow sections. Vertical descent is less than 800m.
Ski 2. Few technical difficulties. Slopes do no exceed 35°.
Ski 3. Some technical sections. Long slopes at 35° with very short sections at 40-45°.
Ski 4. Couloir or steep skiing : slopes between 40 and 45° over more than 200m vertical.
Ski 5. Starts with slopes of 45°-50° during more than 300m vertical or above 50° for more than 100m vertical.

Exposure

The exposure grade does not take into account objective hazards (stone fall, seracs…) but only the consequences of a the skier falling.

Exposure 1  : Exposure is limited to that of the slope itself. Getting hurt is still likely if the slope is steep and/or the snow is hard.
Exposure 2  : As well as the slope itself, there are some obstacles (such as rock outcrops) which could aggravate injury.
Exposure 3 : In case of a fall, death is highly likely.
Exposure 4  : In case of a fall, the skier faces certain death.