Lifting Accessories, Slings and Lifting Equipment
Lifting accessories include chain slings, wire rope slings, webbing slings, round slings, shackles, hooks, eyebolts, lifting beams and plate clamps. Each has a safe working load (SWL) or working load limit (WLL), a unique identifier and a thorough examination regime. You must know how to identify and reject defects: cuts, abrasion, broken wires, corrosion, heat damage, chemical attack, distorted or cracked shackles, missing or illegible tags, damaged safety catches, and hooks that have been spread or have lost their throat opening. Colour coding is used on many sites for periodic inspection status - but colour alone is not proof of fitness; check the tag and the condition.
Rating depends on configuration. A sling's capacity changes with the angle of its legs and with the type of hitch (vertical, choker, basket). Choker and basket configurations have different capacity factors, and multi-leg slings are rated for a stated angle. Shackles must be rated, pin fully engaged, and never side-loaded. Eyebolts must be loaded along their axis. Hooks need safety catches and must not be tip-loaded.
Traps: assuming a 4-leg sling gives four times the capacity; ignoring the effect of sharp edges on webbing; using damaged or unmarked equipment 'just this once'; and mixing accessories from different systems. Always inspect before use, store correctly, and quarantine defective items.
Rule of thumb: no tag, no lift; sharp edge, protect it; and never exceed the stated angle rating.