Red Seal Mobile Crane Operator Practice Exam

Describe the term "outrigger" in reference to mobile cranes.

1. Additional counterweights that improve stability

2. Extendable supports that stabilize the crane and distribute the weight during lifting operations

3. A mechanism that rotates the boom of the crane

4. Controls on the crane used to adjust its height

The correct answer is: Extendable supports that stabilize the crane and distribute the weight during lifting operations

The term "outrigger," in the context of mobile cranes, refers to extendable supports designed to stabilize the crane during lifting operations and to distribute its weight effectively. Outriggers extend out from the main body of the crane to widen its base and enhance stability. This is particularly important when lifting heavy loads or when the crane is positioned on uneven ground. By providing additional support at strategic points, outriggers help prevent the crane from tipping over and ensure safe operation. The effectiveness of outriggers lies in their ability to create a broader stance, which contributes to balancing the crane's center of gravity. This is crucial for maintaining the crane's overall stability when in use, especially given the dynamic forces at play during lifting operations. Properly set outriggers enable the crane to function at its rated capacity, minimizing the risk of accidents. In contrast, the other options are distinctly different functions or components. The mention of additional counterweights relates to ballast used for enhancing stability from a different angle rather than expanding the footprint of the crane. The mechanism that rotates the boom refers to a specific part of the crane's operational function, while controls for adjusting height pertain to the crane's movement rather than its stability features.