Semi-static or dynamic rope: how to choose the right rope

The right rope depends on what you need to do. Elastic cords with hooks hold down tarpaulins and light loads; fibre lines and braided ropes are for tying and pulling; for rope work and fall arrest systems, use only EN 1891 certified low-stretch kernmantle ropes. In the collection the diameters range from 8 to 12.5 mm and the weight per metre from 43 to 115 g. A rope meant for tying loads must never be used to support a person.

The types

• Elastic cords: with hooks, for holding down tarpaulins and light loads on vehicles or stacks. They are not suitable for supporting heavy loads or people.
• Fibre lines and ropes: in polyester, polyamide, polypropylene or jute, for tying, pulling, securing and packing.
• Low-stretch kernmantle ropes: they stretch very little under load and are designed for rope work. Petzl offers them, for example, in the models Axis 11 mm with one sewn termination and Parallel 10.5 mm Custom. The collection also includes Flow, Control, Beam and Duraline: check the product page to see what each one is intended for.
• Lanyards: short ropes for connections and anchor points, such as the Petzl lanyards.
• Rope protectors: to be placed over edges to prevent abrasion and cuts, such as the Roller Coaster protector.

How to choose by job

The features to look at

• Diameter (mm): in the collection it ranges from 8 to 12.5 mm. It must be compatible with the devices you use (descenders, rope clamps): check the diameter range stated for each device.
• Material: polyester sheath and polyamide core in low-stretch kernmantle ropes; polypropylene, polyester or polyamide in lines; rubber in elastic cords; jute for light tying.
• EN 1891 standard: this is the standard for sheath-and-core ropes with low elongation. If the rope is used to support a person, it must carry this marking.
• Static elongation: in low-stretch ropes it ranges from 2.3% to 3.4%; a lower value means less bounce when you put your weight on the rope. The data also show a higher value, 8.5%.
• Sheath percentage: the share of sheath in the weight of the rope, from 36% to 62% in the collection. A thicker sheath protects the core better from wear.
• Construction (carriers): 24, 32 or 40 carriers indicate how the sheath is braided.
• Weight per metre: from 43 to 115 g. It matters if the rope has to be carried over the shoulder or hung over tens of metres.
• Warranty: 3 years on some models: check the product page.

Common mistakes

• Using an uncertified rope for fall arrest or rope work. Only certified low-stretch kernmantle ropes should be used for this purpose.
• Running the rope over edges without protection. A sharp edge is enough to cut it; a rope protector costs far less than a new rope.
• Leaving the rope near chemicals or heat sources. Synthetic fibres degrade, sometimes without any visible sign.
• Not checking it before every use. Cuts, stiffened sections or a damaged sheath are reasons to discard it.
• Choosing the diameter by eye. A device used with a rope outside its diameter range will not work as intended.

Frequently asked questions

What is the difference between a low-stretch kernmantle rope and an elastic cord?

The low-stretch rope stretches very little under load (from 2.3% to 3.4% in the data) and is certified for rope work. The elastic cord stretches a great deal and is only for holding down tarpaulins or light loads.

When should I discard a rope?

If it has cuts, stiffened sections or a damaged sheath, or if it has been exposed to chemicals or heat. If in doubt, do not use it to support people.

What does 32 carriers mean?

It indicates how the outer sheath of the rope is braided. It is a construction detail that helps you compare similar models.

Do I need a rope protector?

Yes, every time the rope runs over an edge or a rough surface. Abrasion and cuts are among the most common types of damage.

You will find lines, ropes and accessories in the Synthetic Ropes and Lines collection; to choose the right model for your job, ask for a quote or advice from the AMES technicians.