1-4 Missouri Valley Practice Test

Joining two slings with a knot is not an acceptable practice in rigging. Knots weaken the sling and create unpredictable load paths, which can cause failure at the knot even when the overall load seems well within the rated capacity. The working load limit assumes a straight, knot-free lift; a knot concentrates stress and can slip or damage the fibers. So the idea that the load being under half the WLL makes it okay is not correct. The safe approach is to avoid knots entirely and connect slings with proper hardware (master links, rated connectors, or suitable lifting hardware) or use a single sling of adequate capacity.