Climbing Main Rope Basics & Usage Standards

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On June 6, 2025

I. Climbing Main Rope Basics

The rope is one of the most important pieces of equipment for a climber, so selection must be done carefully. Climbers categorize climbing in many ways, and rope manufacturers correspondingly produce different types of ropes.

After reading this document, you will have fundamental knowledge for selecting and using ropes.

II. Construction of Dynamic Rope

Manufacturers categorize ropes into 2 types: dynamic ropes and static ropes.

Static ropes cannot absorb impact force through stretching, are more durable than dynamic ropes, and are generally used as fixed lines (e.g., for ascending/descending established routes), but are never used as belay ropes for lead climbing.

Dynamic ropes can stretch to absorb the impact force generated by a fall and are specifically designed for lead belaying. This document focuses specifically on dynamic ropes.

Modern ropes consist of a kernmantle construction (core and sheath), which protects the rope from abrasion.

1.Length

Rope length is generally measured in meters. Nowadays, 55m and 60m ropes have replaced the older 50m standard.

Longer ropes, while heavier, allow climbing longer pitches. Manufacturers typically produce ropes in lengths of 50m, 55m, 60m, and 70m.

2.Diameter

Diameter is usually expressed in millimeters.

15 years ago, 11mm diameter was popular; today is the era of 10.5mm and 10mm, with some single ropes even at 9.6mm and 9.9mm.

Larger diameter ropes offer better safety factors and durability; thinner ropes are generally used for mountaineering protection (e.g., glacier travel).

3.Weight

Weight is usually calculated in grams per meter (g/m).

Weight is a better indicator than diameter alone.

Do not prioritize light weight by choosing a rope with an excessively small diameter.

4.Rope Testing Standards

The International Mountaineering and Climbing Federation (UIAA) is the authoritative body that develops rope testing standards.

5.Falls

The UIAA standard test for rope strength is called the fall test. For testing a single rope, an 80kg mass is used.

The test involves fixing one end of the rope and dropping a 9.2-foot (2.8-meter) length of rope a total height of 16.4 feet (5 meters), producing a fall factor of 1.8 (fall height divided by rope length). The theoretical maximum fall factor is 2.

The higher the fall factor, the more limited the rope’s ability to absorb impact energy. During the test, the 80kg mass is dropped repeatedly until the rope breaks.

The UIAA fall test environment is more severe than actual climbing conditions.

If a rope withstands 7 falls in the test, it does not mean you must discard it after 7 actual falls in the field.

However, if a fall involves a very long length of rope, you should consider retiring it.

6.Impact Force

Impact force is also measured during the fall test.

The UIAA maximum standard for impact force on the first fall is 985kg (12kN).

7.Static Elongation

Measured by suspending a 65kg (143lb) weight from one end of the rope and measuring the elongation.

Dynamic ropes will definitely elongate somewhat under load; the UIAA standard is 8% or less.

However, during a fall it’s different; ropes in the UIAA test can elongate 20-30%.

8.Sheath Slippage

When subjected to friction, the rope sheath can slide along the core. In the UIAA test, a 2.2-meter rope suspending a 45kg mass is pulled over a sharp edge 5 times.

The sheath slippage should not exceed 4cm.

III. Main Rope Usage Standards

1.Marking Ropes

All ropes must be permanently marked at both ends with an ID number and date, sealed with a transparent heat-shrink tube.

If shortening a rope, it must be remarked (including the original date), clearly indicating the new length, and sealed with a transparent heat-shrink tube.

Rope End Marking: Permanent ID/Date at ends.

Middle Marking: Can use colored thread woven into the rope at the midpoint.

Avoid: Marking the middle with ink or markers.

If the middle mark disappears, re-mark the midpoint using tape or thread.

Important: Markers (even those sold by rope manufacturers) have been proven to reduce rope strength.

2.Storage

Ropes should be stored in a clean, dry, room-temperature environment, away from direct sunlight, chemicals, oil-based products, and other liquids.

Ropes should be exposed to air; avoid sealing them in airtight containers.

Ropes should be coiled using the Butterfly Coil method for storage. Mountain Coiling (Mountaineer’s Coil) can cause kinks.

Suitable: Butterfly Coil for storage.

Avoid: Long-term storage by hanging.

3.Tracking (Logging)

Each new rope should be logged using a “Rope Log” form. The form should include:

1) Purchase Date

2) Rope’s internal ID number, diameter, length, brand, color, and specific maximum number of lead falls.

3) or each activity where the rope is used, record:

a, Date of use

b, Number of days used

c, Nature of activity (Winter glacier travel, Summer glacier travel, Ice climbing, Rock climbing)

d, Any incident damaging the rope (e.g., lead fall, rockfall, ice axe or crampon puncture, contact with suspicious liquids, etc.)

Recording rope usage and damage should be an essential part of reports by guides or camp managers.

Rope Log (Reference CMC).

4.Manual Inspection

Inspect the rope by bending it gently section by section, feeling with your hands.

After each activity, briefly look over and check the rope for damage.

Wet ropes are best spread out flat on clean ground (not hung). Do not place ropes directly on concrete, as they can absorb toxic substances from it.

After each summer and winter season, ropes should undergo a thorough inspection for damage.

Uncoil the rope and carefully feel along its entire length while visually inspecting. Bend the rope gently section by section, looking for possible sheath damage.

Minor Damage: Fuzziness/fuzz that doesn’t affect the core is not significant damage.

Severe Damage: If you feel a lump or soft spot, if the rope doesn’t bend smoothly at a point, or if it kinks easily into a sharp angle, the rope must be cut (to remove the damaged section) or retired.

If the core separates from the sheath, this indicates the rope has suffered permanent damage.

Sheath Damage: A few cuts/scratches in the sheath are acceptable only if they are superficial and do not expose the core.

Cut off any loose strands of sheath to prevent further unraveling.

5.Cleaning

If a rope becomes dirty, it should be cleaned.

Hand wash in cool water. Machine washing is possible using a front-loading washing machine’s “cold water” or “delicate” cycle; ensure thorough rinsing.

Avoid: Top-loading (agitator) washing machines, as they can stretch and damage the rope.

Use “Zero” or similar mild, non-detergent soap, or a neutral pH detergent.

Spread out flat to air dry completely.

6.Retiring Ropes

Retirement Schedule based on Usage Frequency:

Rarely used: 7 years (2-3 times per year)

Occasionally used: 5 years (~1 time per month)

Regularly used: 3 years (Several times per month)

Frequently used: 1 year (Weekly)

Daily use: Less than 1 year

Retire a rope immediately if damaged by rockfall, crampons, or sharp rock edges.

If damage is confirmed to be only at one end, the damaged section can be cut off and the remaining rope may continue to be used.

Retire a rope when the number of lead falls it has sustained approaches its rated maximum (each new rope has a specific rating).

If a rope experiences a fall with a fall factor of 2 (fall distance equals twice the length of rope paid out), it must be retired immediately.

Re-Purposing:

Single Rope: If a main rope has sustained fewer lead falls than its rated maximum, has suffered no severe damage, and shows no visible deterioration, after 1 to 5 years (depending on usage frequency) it should be downgraded for top-roping use only.
- Note: Top-roping is very abrasive; such ropes must still be manually inspected frequently as described above.

Twin/Double Rope: If a twin/double rope has sustained fewer lead falls than its rated maximum, has suffered no severe damage, and shows no visible deterioration, after 1 to 5 years (depending on usage frequency) it should be downgraded for glacier travel use only. Such ropes must also be manually inspected frequently.

When a rope’s water-repellent treatment is noticeably degraded, it should no longer be used for ice climbing.

When the sheath shows multiple cuts/scratches (even if core isn’t exposed) or becomes “fluffy,” stop using it for lead climbing and use it only for top-roping or glacier travel.

IV. Selecting the Appropriate Rope

All technical lead climbing and top-roping must use a rope classified as a Single Rope (diameter typically 9.5mm to 11mm – check manufacturer specifications).