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Status: STD 2005/06/07
Code: 1073

Concept definition: In North America, the relative difficulty of traversing a <RAPID>, based on the Safety Code of American Whitewater; rapid class.
Attribute value type: ENUMERATION
Reference type: IR
Reference: [SCAW]
Supplemental references:  

Enumerants (presented in a natural order)
Status Attribute label Enumerant label ▾ Concept definition Code Ref type Reference Supplemental references
RAPID_CLASS I Class I: Easy. Fast moving <WATER> with riffles and small <WATER_WAVE>s. Few obstructions, all obvious and easily missed with little training. Risk to swimmers is slight; self-rescue is easy. 1 IR [SCAW, VI, "Class I Rapids"]  
RAPID_CLASS II Class II: Novice. Straightforward <RAPID>s with wide, clear channels which are evident without scouting. Occasional maneuvering may be required, but <STONE>s and medium sized <WATER_WAVE>s are easily missed by trained paddlers. Swimmers are seldom injured and group assistance, while helpful, is seldom needed. <RAPID>s that are at the upper end of this difficulty range are designated "Class II+". 2 IR [SCAW, VI, "Class II Rapids: Novice"]  
RAPID_CLASS III Class III: Intermediate. <RAPID>s with moderate, irregular <WATER_WAVE>s which may be difficult to avoid and which can swamp an open canoe. Complex maneuvers in fast <WATER_CURRENT> and good boat control in tight passages or around ledges are often required; large <WATER_WAVE>s or strainers may be present but are easily avoided. Strong eddies and powerful <WATER_CURRENT> effects can be found, particularly on large-volume <RIVER>s. Scouting is advisable for inexperienced parties. Injuries while swimming are rare; self-rescue is usually easy but group assistance may be required to avoid long swims. <RAPID>s that are at the lower or upper end of this difficulty range are designated "Class III-" or "Class III+" respectively. 3 IR [SCAW, VI, "Class III: Intermediate"]  
RAPID_CLASS IV Class IV: Advanced. Intense, powerful but predictable <RAPID>s requiring precise boat handling in turbulent <WATER>. Depending on the character of the <RIVER>, it may include large, unavoidable <WATER_WAVE>s and holes or constricted passages demanding fast maneuvers under pressure. A fast, reliable eddy turn may be needed to initiate maneuvers, scout <RAPID>s, or rest. <RAPID>s may require "must'' moves above dangerous hazards. Scouting may be necessary the first time down. Risk of injury to swimmers is moderate to high, and water conditions may make self-rescue difficult. Group assistance for rescue is often essential but requires practiced skills. A strong Eskimo roll is highly recommended. <RAPID>s that are at the lower or upper end of this difficulty range are designated "Class IV-" or "Class IV+" respectively. 4 IR [SCAW, VI, "Class IV: Advanced"]  
RAPID_CLASS V Class V: Expert. Extremely long, obstructed, or very violent <RAPID>s which expose a paddler to added risk. Drops may contain large, unavoidable <WATER_WAVE>s and holes or steep, congested chutes with complex, demanding routes. <RAPID>s may continue for long distances between pools, demanding a high level of fitness. What eddies exist may be small, turbulent, or difficult to reach. At the high end of the scale, several of these factors may be combined. Scouting is recommended but may be difficult. 5 IR [SCAW, VI, "Class 5: Expert"]  
RAPID_CLASS VI Class VI: Extreme and Exploratory. These runs have almost never been attempted and often exemplify the extremes of difficulty, unpredictability and danger. The consequences of errors are very severe and rescue may be impossible. For teams of experts only, at favourable water levels, after close personal inspection and taking all precautions. After a Class VI <RAPID>s has been run many times, its rating may be changed to an appropriate Class 5.x rating. 6 IR [SCAW, VI, "Class VI: Extreme and Exploratory Rapids"]  

Group membership:

In addition to the status and date information for each entry, a colour coding scheme highlights the database holding to which an entry belongs. The following highlight colours are used:

  • white - the entry is in the standard
  • yellow - the entry has been added to the register
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  • cyan - a deprecated entry that was originally either in the standard or was added to the register, but has since been deprecated

The following icons are used to identify items that have figures, modifications and/or clarification notes:

  • F n - has Figures and, if more than one figure, n figures
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