DYNAMIC ROPE                                                                                   .

STRENGTH, ENERGY ABSORBING AND FALL FACTORS:

1. Dynamic ropes used by HRA have a breaking strength exceeding 2200 Kg

2. Knots weaken ropes by 25-45%.  We only use figure-of-eight knots, reducing strength by about 25%

3. Ropes are weakened by running over sharp or tight bends e.g. weakened by up to 30% if bent over a single 10mm karabiner.  If diameter of 'sheave' is increased to 33 mm then the rope retains 80% of its strength and if increased to over 100 mm (e.g. Shear reduction block) then the loss in strength is negligible, all our belay ropes are always run over Shear reduction blocks, except in some rescue situations.

4. If ropes are not properly maintained they will be weaker (see maintenance and inspection)

5. The most important aspect of a dynamic rope (over other ropes) is its ability to absorb energy by stretching - thereby exerting less force on the climber

6. Rope's ability to absorb energy is proportional to the length of rope involved. The fall factor is calculated by dividing the length of the fall by the length of rope available.

7. Fall factors give an indication to the severity of the load (impact force) on the climber and belay system.

8. A fall factor greater than 1 is serious.  On our ropes course the maximum fall factor that is likely is 1, and more often than not it is less than 0.1

INSPECTIONS MAINTENANCE AND CARE:

1. Rope is a vital piece of equipment so its condition is of paramount importance.

2. Affected by heat - including friction caused by rope over tape etc.

3. Affected by large falls - replaced in accordance with manufacturers    recommendations, but always discard if it has suffered a fall factor greater than 1.0, or shows wear.

4. Affected by chemicals and by sunlight (ultra-violet)

5. Amount of furring gives indication as to the amount of use a rope has had

6. Ropes are never stood on, or run over sharp edges

7. Ropes are kept clean - washing in warm water, mild soap etc.

8. Soft spots should mean retiring a rope or those sections being removed

9. Stored in a cool, dry, dark and well-ventilated environment

10. Maintained and replace in accordance with manufacture's recommendations

Belay ropes are not left out on the ropes course when it is not in use - particularly at night. This helps to prevent unauthorized access and will help safeguard the integrity of the rope.

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