The hoist chain was used for rigging. This should never be done. Per ASME B30.16-3.1.2 (a) The hoist chain shall not be wrapped around the load. (b) The load shall be attached to the load hook by suitable means.
Alloy chains should have been used and connected to the hoist chain. Alloy chains have alloying elements that give this type of chain durability, abrasive resistance and toughness. Hoist chains can fail when used in this manner because they have a high hardness. The lift wheel of the hoist and chain are calibrated for proper functioning of the hoist.
Additionally, when using the proper rigging chain sling in this manner, protective padding must be used. Per ASME B30.9-1.10.4 (d) Sharp edges in contact with the sling should be padded with material of sufficient strength to protect the sling.
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