What is the minimum angle at which slings should not be used in relation to the horizontal plane of the load?

The minimum angle at which slings should not be used in relation to the horizontal plane of the load is 45°. This angle is crucial in rigging practices because it helps to ensure that the load is balanced and stable during lifting operations.

When slings are used at angles less than 45 degrees, they can impose excessive stress on the sling and the rigging hardware, which may lead to an increased risk of failure. At angles below this threshold, the effective weight supported by the slings increases because a larger portion of the load's weight is distributed horizontally rather than vertically. This can also lead to lateral movement or swinging of the load, creating potential hazards for personnel in the vicinity.

By adhering to the guideline of a minimum angle of 45 degrees, riggers can promote safer lifting practices. This angle helps to distribute the weight evenly, minimizes the risk of excessive sling tension, and promotes stability during lifting. Ensuring that the slings are positioned correctly not only protects the integrity of the rigging equipment but also enhances overall safety on the job site.