When is it necessary to destroy and replace the positioning strap of climbing equipment?

The necessity to destroy and replace the positioning strap of climbing equipment is particularly triggered when the red warning core is exposed. This red core serves as a critical indicator of potential failure and safety risk. Exposure of this core signifies that the strap may have reached a level of deterioration that compromises its structural integrity, posing a significant danger to the user. A positioning strap is designed to support and secure a climber; thus, any visible sign of wear or damage, notably the alarmingly revealing of its internal components, mandates immediate replacement to ensure the highest standards of safety in climbing operations.

Other options, while they might suggest concerns about the strap's condition, do not represent as definitive a standard as the exposure of the red warning core. Signs of wear and unusual stiffness could vary in severity and may not always indicate an imminent failure. The one-year usage criterion may not be universally applicable, as the actual lifespan can depend on usage specifics and environmental factors. Therefore, the unequivocal threshold is the visibility of the warning core, which directly mandates action for the user's safety.