Inspecting Rigging Before Use
Why inspection comes first
Every lift begins with an inspection, and exam questions reward the habit of rejecting damaged gear before it is loaded. Know the removal criteria for the major components: slings (wire rope, chain, synthetic web), shackles, hooks, master links, swivels, and hardware.
Common removal criteria to memorize
- Wire rope slings: broken wires, kinking, bird-caging, crushing, corrosion, heat damage, or a broken strand. Reject hooks with cracks, deformation, or a throat opening increased more than 15 percent.
- Chain slings: cracks, stretched links, gouges, nicks, bent or twisted links, and excessive wear (commonly 10 percent reduction in link thickness or a stretch indicating overload).
- Synthetic web slings: burns, holes, tears, snags, embedded grit, ultraviolet degradation, and missing or illegible tags. Red warning yarn showing through the cover is a reject.
- Shackles and hooks: bent pins, cracked bodies, missing safety latches, and worn threads.
Traps to watch
Questions often test the tag requirement (all slings must carry a legible identification tag), the difference between surface damage and structural damage, and whether a safety latch is mandatory on hooks used for lifting. Another trap: confusing inspection intervals with removal criteria. A periodic inspection schedule does not excuse a pre-use inspection.
Rule of thumb
If you cannot read the tag, you cannot verify the rated capacity, so the item is out of service until re-tagged. When in doubt, remove it from service - the cost of a sling is trivial compared with a dropped load.
Worked example
A chain sling shows a link worn from 13 mm to 11.8 mm. Reduction = 1.2/13 ≈ 9.2 percent, under the 10 percent threshold, but the gouge and twist still justify rejection. Inspect against every criterion, not just one number.