The A-B Descender has been designed for Technical Rope Access, Intervention/Special Forces and Rescue. It has been designed to overcome some of the problems that occur with other devices and comply fully, with the correct European Standard for this type of descender/rope adjustment device.
The A-B Descender conforms to two standards EN12841-C as a Rope Adjustment device (Descender) and EN341-C Descenders for Rescue. The two standards are very different. EN12841-C covers the device only, so that it can be used different types of Kernmantle rope, in accordance with the SAR user instructions. EN341 is the standard for a decent rescue/egress system and any system conforming to this standard must be used with the rope with which it was tested.
Over the past ten years the EN12841 standard has been adjusted to suit the requirements of the users. Testing cannot be done on all rope types, diameters and conditioning as this could take years and the cost be too restrictive, so the user has to understand that each rope used in the device with this standard will give a different reading in test’s or feel in use.
Some of the problems with other descenders are creep, too sensitive, panic brakes too slow or fast to activate, unable to pull rope through easily or not at all and over complicated design. With the A-B Descender we hoped to have overcome all these with the simplicity of its design. The A-B Descender has had some design changes from suggestions of users of the old SCARAB. A spring has been added to help keep the handle close to the body when not in use, a small bobbin as a rope keeper and the main change is a flip down handle to give extra leverage when required and a finer control in descent.
NOTE: All friction brakes create heat which can damage rope if a fall has taken place or on a long fast descent. Any strength quoted is when the product is new and is in accordance with the appropriate standards.
The A-B Descender has been tested by the notified body in a simulated rescue using a 210kg mass as required in 12841-C 4.4.5 and 4.4.9. It has also been tested with 100kg loaded on the descender and 100kg on a one meter wire sling in a fall factor one scenario which is a more realistic test. Maximum impact force recorded was 5.7kN, max slip on rope was 15cm and there was only slight glazing to the rope. There was no damage to rope or descender. SAR confirms it can be used in RESCUE with a two person load. The A-B Descender also conforms to EN341-C for 20 x 100M descents with 100kg mass using SAR 16 plait 11mm low stretch rope. 12841-C is a far higher standard than EN341, the number of descents and distance is irrelevant. In EN12841-C you can descend as many times as required and at whatever distance. The only ruling factor in this standard is degradation on the descender and rope.
•Colour: GOLD or BLACK
•Rope: 10.5mm to 12.5mm Kernmantle
•Max Load: 300kg
•Control: Leaver/Cam + Panic Grab Brake.
•Min. Static Slip: 4.5kN 10.5mm x 22 plait •Route 44 Singing Rock, 5.5kN 11mm x 24 •plait SAR. 8kN 12.5mm x 20 plait Cousin
•Dynamic Impact and slip distance 100kg •FF1-1M: 10.5mm = 5.1kN & 51cm, 11mm = •6.2kN & 26cm, 12.5mm = 7kN & 15cm