7-4 | Basic Inspection Criteria
The goal of a sling inspection is to evaluate remaining strength in a sling which has been used previously to determine if it is suitable for continued use. When inspecting synthetic rope slings, daily visual inspections are intended to detect serious damage or deterioration which would weaken the strength and integrity of the sling.
If during any point of the inspection the following is observed, a synthetic rope sling should be removed from service, according to ASME B30.9 standards:
Missing or illegible sling identification
Cuts, gouges, areas of extensive fiber breakage along the length, and abraded areas on the rope
Damage that is estimated to have reduced the effective diameter of the rope by more than 10%
Uniform fiber breakage along the major part of the length of the rope in the sling such that the entire rope appears covered with fuzz or whiskers
Inside the rope, fiber breakage, fused or melted fiber (observed by prying or twisting to open the strands) involving damage estimated at 10% of the fiber in any strand or the rope as a whole
Discoloration, brittle fibers, and hard or stiff areas that may indicate chemical damage, ultraviolet damage, or heat damage
Dirt and grit in the interior of the rope structure that is deemed excessive
Foreign matter that has permeated the rope and makes it difficult to handle and may attract and hold grit
Kinks or distortion in the rope structure, particularly if caused by forcibly pulling on loops (known as hockles)
Melted, hard, or charred areas that affect more than 10% of the diameter of the rope or affect several adjacent strands along the length that affect more than 10% of strand diameters
Poor condition of thimbles or other components manifested by corrosion, cracks, distortion, sharp edges, or localized wear
For hooks, removal criteria as stated in ASME B30.10
For rigging hardware, removal criteria as stated in ASME B30.26
