National Commission for the Certification of Crane Operators (NCCCO) Mobile Crane Practice Exam

The effective weight of the jib is the correct factor in determining the amount of deduction required for an erected jib that is not being used. Effective weight takes into consideration the actual weight of the jib and how it affects the crane's stability and lift capacity. When a jib is erected but not in use, it still contributes to the overall balance and center of gravity of the crane, which is why you must account for its effective weight for calculations related to lifting operations. This ensures that the crane remains within its safe operational parameters, factoring in the potential impact on stability and performance. In contrast, the actual weight of the jib alone does not account for its implications on crane dynamics while it is erected. Simply stating "nothing" because the jib is not in use overlooks the essential safety considerations involved in lifting operations. The difference between the crane's actual weight and its effective weight is a more complex calculation that does not directly help in determining the specific deduction required for the jib itself.