Fall factor

Fall factors

The fall factor is a parameter in the event of a fall into fall arrest equipment (rope, energy absorber, fall arrest device, ...), as it can occur in climbing , in rope-assisted work processes and in rope-assisted tree climbing techniques . ${\displaystyle f_{s}}$

The fall factor is calculated as the quotient of the height of the fall and the length of the lanyard issued (e.g. the rope including the connecting elements ( carabiner ) to the eyelet of the climbing harness ): ${\displaystyle h}$ ${\displaystyle l}$

${\displaystyle f_{s}={\frac {h}{l}}}$

meaning

The fall factor is a variable in the generation of forces ( impact force ) in a fall arrest system (when climbing or when using personal protective equipment against falls at work).

Since you can usually not fall more than twice the specified length of the connection between the anchor point and the harness (see graphic), the maximum fall factor is 2 (corresponds to a fall of the lead climber into the stance during alpine climbing without intermediate securing ). An exception are via ferratas or "securing" to vertical structures such as pipes or ropes.

When testing ropes , the standard fall is used to compare the quality of the ropes. The standard fall is certified according to  EN , its fall factor is approximately 1.7.

See also

• Number of falls

literature

• Helmut Mägdefrau: The strain on the human body when falling into a rope and its consequences. Dissertation Munich Ludwig Maximilian University. 1989.

Web links

• Christian Katlein: Fall factor and occurring force (PDF file; 867 kB)