Device for warning about the absence of belaying of a climber

A method for warning about the absence of belaying of a climber equipped with a harness to which a link is attached, the link being held by a belaying system with a final positive incline with respect to a horizontal reference plane, the method comprising the following steps:

• a) providing an enclosure, fastened to the harness;
• b) arranging a pressure sensor in the enclosure to measure a barometric pressure;
• c) fastening a detector to the link;
• d) configuring the detector so as to:
• detect a movement of the link within a range of positive inclines with respect to the horizontal reference plane, the final positive incline being contained within the range of positive inclines;
• and
• output a detection signal comprising:
• a first state, indicating that the link is within the range of positive inclines, and
• a second state, indicating that the link is outside the range of positive inclines;
• e) arranging a microprocessor in the enclosure, said microprocessor being connected to the pressure sensor and to the detector;
• and
• f) configuring the microprocessor so as to:
• compute a variation in the barometric pressure measured by the pressure sensor, and
• send a warning signal if and only if the variation in the barometric pressure exceeds a predetermined threshold and the detection signal is in the second state.