Sling with predictable pre-failure warning indicator

Abstract From the Canadian patent

A pre-failure warning indicator is provided for use with a sling. The pre-failure warning indicator triggers at a point that is predictable within a relatively narrow range thereby increasing the possibility that a damaged sling is removed from use. The pre-failure warning indicator includes a dedicated strand of material that is placed in close proximity to the load-bearing core yarns of the sling but remains separate and independent from the core yarns; the ends of the dedicated strand are connected via a sacrificial "ring." A warning fiber having an end that is visible to operators/riggers works in conjunction with the sacrificial strand and the ring. The ring is designed to fail when …