Canyon Rating System
I. Technical Classification
Class 1 - Canyon Hiking Non-technical. No rope is required. See the route description for difficulties.
Class 2 - Basic Canyoneering Scrambling, easy climbing or downclimbing. A rope may be handy for handlines, belays, lowering packs and emergency use. Exit or retreat possible upcanyon without fixed ropes.
Class 3 - Intermediate Canyoneering Rappels or technical climbing and/or downclimbing. A rope is required for belays and single-pitch rappels. Retreat upcanyon would require fixing ropes.
Class 4 - Advanced Canyoneering Aid climbing, multi-pitch rappels and/or complex rope work(such as re-belays, tyrollean traverse, or guided rappels) may be required. Might also require difficult pothole escapes, serious squeezing, extensive high-risk downclimbing, or have difficult-to-establish natural anchors. Rappels longer than 200 feet will usually earn a canyon a Class 4 rating.
The difference between Class 3 and Class 4, for me, is the difference between canyons that medium-skill climbers can comfortably complete (Class 3) and those that require canyoneering experience or specific canyoneering skills (Class 4).
II. Water: Pools/Current/Etc.
A - Normally dry or with very little water. Wading to waist deep at most.
B - Water with no current or light current. Still pools. Falls are normally dry or running at a trickle. Swimming expected.
C - Water with strong current. Waterfalls. Wet canyon rope techniques required.
III. Grade: Time Required and Seriousness
I - Short. A couple of hours.
II - Requires about a half day.
III - Normally requires most of a day.
IV - Expected to take a long day. Get up early, bring a headlamp. Possible bivy.
V - More than one day. Normally done in two days.
VI - Two full days or more.
IV. Additional Risk / Seriousness
An "R" or "X" in the rating suggests the canyon will involve risks over and above the many risk factors normally found in canyons. Some examples of additional risks are: difficult rappels, exposed climbing or traversing, extensive 4th- or 5th-class unroped climbing, difficult anchors, sections of loose or dangerous rock, difficult or committing route finding, prolonged water immersion or extensive swimming. Specific factors should be addressed in the route description.
(No Rating): Normal risk factors are present on this adventure.
R-Risky: One or more extraordinary risk factors exist that complicate the descent. Solid technical skills and sound judgment required. Not appropriate for beginners, even with competent leadership.
X-Extreme: Multiple risk factors exist that will complicate the descent. Errors in technique or judgment will likely result in serious injury or death. Descent should be attempted by expert canyoneers only.This is the least-well-established part of the rating system, and the most subjective. Use by beta-providers varies widely, to the point that this part of the rating means very little.
For example Wadi Zarqa Ma'ain rate is ( 3 A III )
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