Which section of the ladder is not intended to move on an extension ladder?

The base section of an extension ladder is designed to remain stationary during use, providing stability and support during operations. The base serves as the foundation of the ladder, and it is typically wider and heavier than the other sections, which helps prevent tipping or shifting while the ladder is extended to reach higher places.

In contrast, the fly section of the ladder is the part that extends upward to increase the ladder’s height, and the halyard is the rope mechanism used to raise and lower the fly section. The rungs are the steps on which firefighters will climb. Understanding the structure and function of each section is crucial for ensuring safe and effective use of the ladder while on duty.