On a crane's load chart, what do the numbers above the bold line indicate?

• A. Rated capacities based on the structural strength of the boom
• B. Rated capacities based on the stability of the crane
• C. Maximum load at ground level
• D. Minimum load at rest

Answer: (A)

The numbers above the bold line show the lifting capacities that are limited by the boom’s structural strength. In other words, these values are the maximum loads the boom can safely handle at that reach and boom length, assuming the crane is set up for stability but that the boom’s bending and overall strength would be the controlling factor. The bold line separates this “boom-strength limited” region from the stability-limited region, where the crane’s stability (outriggers, ballast, base) would govern the allowable load.