Rigging hardware should be removed from service when wear exceeds ?.

• A. 3%
• B. 5%
• C. 8%
• D. 10%

Answer: (D)

Wear reduces the cross‑sectional area that carries the load, so rigging hardware must be retired once the material loss reaches a point where strength is no longer reliably enough. The standard threshold used in many safety guidelines is 10% wear of the original dimension (such as the diameter of a shackle pin or the wall thickness of a hook). Reaching or exceeding this level meaningfully weakens the part, increasing the chance of failure under load, so removing it from service at 10% wear provides an appropriate safety margin. Lesser percent wear (3%, 5%, or 8%) would allow more deterioration before retirement, which is not as safe. If you observe any cracks, deformation, or other damage, discard it regardless of the percent wear.