Safety chain

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In climbing and occupational safety , for example, the term safety chain refers to a system of equipment such as snap hooks , ropes and climbing harnesses that are intended to protect people from falling during activities at risk of falling .

Depending on the intended use, the safety chain consists of different elements.

Climb

When climbing, the safety chain is made up of the items of equipment that absorb and transmit the forces that occur if the climber falls or hangs freely on the rope.

In the event of a fall, dynamic forces are created when the potential energy released by the climber is absorbed by the safety chain over a certain period of time.

In the case of hanging in the rope, only static forces occur that are lower than the dynamic forces acting in the event of a fall. In the static case, too, forces can act within the safety chain that theoretically exceed the static weight of the climber hanging in the rope by up to twice (addition of weight and holding force at the deflection). In general, the forces that occur in different elements and sections of the safety chain are of different magnitude, with the highest values ​​being observed at the deflection.

Elements and structure

The security chain essentially consists of the following elements:

  • the harness of the climber
  • the rope that connects the climber to the belayer via the deflection point
  • a turning point where the climber hangs after the fall
  • the connection between the rope and the deflection point
  • a backup device that reduces friction on the rope the necessary for the braking force belayers
  • a fixed point to which the belay device is attached and which absorbs the force acting on the belay device. Depending on the situation, the belaying partner can also take on the role of the anchor with his or her body weight .

Every safety chain is only as good as the weakest of its links. All important elements of a security chain must therefore be designed redundantly or oversized - based on the expected maximum load. When climbing, a tensile strength and breaking strength of at least 22 kN has proven itself for almost all elements  . Elements of the safety chain that can be opened are usually to be secured against unintentional opening.

See also

literature