An extension ladder must extend ______ feet above the landing.

An extension ladder must extend a minimum of 3 feet above the landing to ensure safety when using the ladder. This height provides a stable handhold for individuals when transitioning on and off the ladder, allowing them to maintain three points of contact—two hands and one foot or two feet and one hand—while climbing or descending.

This safety measure helps prevent falls by letting users grasp the ladder securely while moving off it and ensures they have something to hold onto as they step onto or off the landing. Options indicating a greater extension, while potentially offering increased safety, are not the minimum requirement established by safety standards. Therefore, 3 feet is the crucial benchmark that meets the necessary guidelines for safe ladder use.