Ascenders, Descenders & Belay Devices

Frequently asked questions

What is the difference between an ascender, a descender and a belay device?

An ascender grips the rope with a toothed cam so that it slides up but locks under load, letting a user climb a fixed rope. A descender creates controlled friction so the user can lower themselves, and handle-operated or anti-panic models let the user stop and hold position hands-free. A belay device is used by a second person to hold and pay out a climber's rope and is also used for abseiling.

Why are ascenders rated at 4 or 6 kN when figure-8s list 25 to 40 kN?

An ascender's rating describes the toothed cam holding a rope, and above a certain load the cam begins to damage the sheath, so the figure is far lower than the strength of the metal. For comparison, EN 12841 requires Type B working-line ascenders used in rope access to withstand a 4 kN static load. Ascenders are for static loading only and must never be used to arrest a fall, whereas a figure-8 rating describes the strength of a solid metal body.

Which standards apply to ascenders, descenders and belay devices?

In Europe, mountaineering rope clamps are covered by EN 567, rope access devices by EN 12841 (Type A back-up devices, Type B ascenders and Type C descenders), rescue descenders by EN 341, and belay devices by EN 15151-1 for assisted-locking and EN 15151-2 for manual devices. The right standard depends on how the brand will market the product. Certification is model-specific; in this range, the A906 anti-panic descender is the model listed with CE certification to EN 341 and EN 365.

Should I choose an aluminium or a steel descender rack?

Aluminium keeps weight down: the A908 rack weighs 372 g against 602 g for the steel S908. Steel resists wear from muddy or sandy rope much better, so it suits caving, canyoning and rescue teams that use the same rack heavily. Many brands offer both and let the end user choose.

Can cam material and handedness be specified for ascenders?

Yes. The A696 chest ascender and the AAD-0329L handled ascender list cams in either steel or stainless steel, and the AAD-0327 series uses stainless steel 304. Handled ascenders are offered as left- and right-hand pairs, such as AAD-0327-L and AAD-0327-R, so an order should state the quantity of each.

What should an RFQ for a rope device include?

Give the model code or drawing, the rope types and diameter range the device must work with, cam material, anodised colours, logo marking and packaging. State the standard and market the finished product must meet and whether the brand will hold certification in its own name. Annual volume and any required test documentation help define the production plan.