Shackles in rigging assembly below required safe working load (SWL)
- Safety Flash
- Published on 19 July 2011
- Generated on 20 November 2025
- IMCA SF 07/11
- 1 minute read
A member has reported that during a recent a recent spot check on a lifting bridle it was identified that a 17T shackle had been fitted instead of a 30T shackle.
The preassembled lifting bridle included 3 x 30T shackles (Crosby G2140) and 1 x 17T (Crosby G2130) instead of 4 x 30T shackles. The certificate for the 17T shackle was cross checked against the identification number on the attached tag plate and showed the shackle SWL as 30T. The shackle was removed and replaced with a 30T shackle (30T working load limit (WLL) embossed).
Although the shackles are almost identical in size, differences in the material grades determine the WLL. Both the material grade and WLL are embossed on every shackle. It appears that an error was made during the certification process by the supplier where a 17T shackle had been certified (ID tag attached with common certificate number) as part of a batch of 30T shackles.
This unsafe condition reinforces the requirement to conduct a pre-use inspection of lifting equipment prior to commencing the lift.
different shackles with working load limits embossed
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