Is the length specification of the anti fall device insufficient to lower it to the ground?

Fall arresters are usually limited by the length of the steel wire rope and cannot reach the working height. For example, high-altitude operations at a height of 30 meters have exceeded the conventional length of most fall arresters' steel wire ropes. Can a 20 meter fall arrester be used at such a height?

Firstly, we need to understand that the length specification of the anti fall device wire rope does not necessarily have to reach the working height, which is a misunderstanding in our understanding. We need to recognize that the use of anti fall devices generally involves climbing operations from top to bottom or from bottom to top at heights of tens of meters. The anti fall device is not fixed once and used throughout the entire process, but needs to constantly change the fixing points.

Taking the daily climbing of tower crane drivers as an example, when they climb beyond the specifications of the anti fall device, they usually use a safety rope to use the anti fall device. The method of use is to constantly change the suspension point of the anti fall device to move the position, and finally both the person and the anti fall device reach the lowest point at the same time. This avoids the problem of insufficient length specifications of the anti fall device and inability to continue climbing downwards.