Whistle signals for communication in cases where vision is low or zero or background noise does not allow other communication. With two systems, one by means of rubber to attach to the helmet by means of lark knot, or by means of cordino to carry it hung of the neck.
RECOMMENDED COMMUNICATION CODE: Whistles must be performed energetically and leaving enough separation between them.
- A whistle: Indicates Stop. Maneuver finished.
- Two whistles: Indicate LI-BRE. Rope free when reaching the base of a rappelling.
-Three whistles: They indicate DES-CEN-DER. It is necessary to wind up on a detachable rappelling because it does not reach the base, or the member of the descending group has been blocked.