Inspecting Slings and Lifting Gear: When to Reject Immediately
A worker pulls a webbing sling from the kit. The sewn tag is torn and unreadable, but the webbing looks fine, and the job is behind schedule, so he assumes it is yesterday's sling. That decision alone is enough to stop the lift: a sling without a legible tag has no known capacity and no identity. It is rejected.
1. The Governing Principle
Lifting gear does not fail silently. Damage accumulates and shows as signs you can see and feel well before collapse. The rule is simple: when in doubt, take it out of service. Never field-repair a sling — knots, improvised splices and welding void the original rating entirely.
2. Wire Rope
Run a gloved hand along the full length, concentrating near eyes, terminations and load contact points.
- Broken wires: singles, and especially clusters in one strand or near a termination.
- Kinks: a permanent sharp bend deforms the structure and never recovers.
- Birdcaging: strands splaying outward means lost internal structure. Immediate rejection.
- Corrosion: surface corrosion warrants assessment; deep corrosion, pitting or rust packing the valleys means rejection.
- Diameter reduction: measure and compare against unloaded sections of the same rope. Noticeable loss indicates internal wear or stretch.
- Heat damage: discolouration, weld spatter or unusual softness signal altered metal properties.
- Termination damage: cracks or distortion in ferrules and thimbles.
Allowable limits for broken wires and diameter loss are set by the manufacturer and applicable standard for that rope type. There is no single universal figure.
3. Synthetic Webbing
- Cuts: any cut or tear in the face or, critically, the edges.
- Abrasion: fuzzed surfaces and raised fibres mean lost load-bearing material.
- Heat glazing: shiny, melted or hardened areas where fibres have lost flexibility.
- Chemical attack: staining, discolouration, fibres that crumble when rubbed, or unusual softness. Strength can be gone with little visible warning.
- Stitching damage: cut or pulled threads in the load-bearing seam.
- Tag: missing or illegible means immediate rejection.
- Knots: a knotted sling is rejected; knots concentrate stress and sharply reduce strength.
4. Chain
Clean it first — grease hides cracks — then inspect link by link.
- Stretch: links longer than their neighbours, or a chain that pulls unusually straight. Evidence of past overload.
- Gouges and nicks: any groove or cut concentrates stress.
- Bent or twisted links: deformation of any link rejects the whole assembly.
- Wear at bearing points: progressive thinning where links contact.
- Corrosion: especially deep pitting.
- Welding or heating: any chain welded or heated on site is rejected.
5. Hooks and Fittings
| Item | Check | Reject when |
|---|---|---|
| Throat opening | Width versus a known good hook | Any opening up (overload evidence) |
| Twist | Tip plane relative to the body | Any noticeable twist |
| Latch | Full closure and alignment with the tip | Missing, broken or not closing |
| Body | Cracks, nicks, wear, distortion | Any crack, however small |
| Shackles and rings | Pin straightness, thread condition | Bent pin or damaged thread |
6. Inspection Frequency
- Pre-use: by the user, before every lift. A quick visual and tactile check of the full length.
- Periodic: by a competent person at defined intervals, recorded in a register. The interval is set by local regulations, the manufacturer and severity of use.
- Exceptional: after any incident, suspected overload, heat or chemical exposure, or return from loan or long storage.
7. How to Actually Remove Gear
- Tag it immediately: a red tag or distinctive paint readable from a distance.
- Remove it from the work area: a separate quarantine location, away from serviceable stock.
- Render it unusable: cut the webbing, destroy the eye, part the link. This is the only real guarantee.
- Record it: item, reason, date.
- Find the cause: repeated heat or chemical damage points to a work method or storage problem, not just a bad sling.
Conclusion
Inspection is the last barrier between your crew and an incident. Know what you are looking for in each type: wires, birdcaging and diameter in wire rope; cuts, glazing and the tag in webbing; stretch and deformation in chain; throat, twist and latch on hooks. Make pre-use checks daily habit and periodic inspection a competent person's documented duty. When you reject something, destroy it so it cannot come back. Detailed acceptance limits belong to the manufacturer and local code; the doubt principle always points to rejection.