What is the minimum distance the base of a 40-foot extension ladder should be set from the wall it is leaning against?

The minimum distance that the base of a 40-foot extension ladder should be set from the wall it is leaning against is determined by the angle at which the ladder rests against the wall. The correct answer of 10 feet is derived from the general safety guideline that for every 4 feet of ladder height, the base should be placed 1 foot away from the wall.

In this case, a 40-foot ladder should be positioned so that it is 10 feet away from the wall. This 1:4 ratio creates a safe angle for climbing and working on the ladder, which helps to prevent the risks of tipping or sliding. Proper ladder setup is crucial for ensuring the safety of workers, and adhering to this guideline will significantly reduce the chances of accidents while using the ladder.

Given the height of the ladder, the correct application of this ratio aligns with safety standards established for ladder use in construction and related fields. Using this guideline ensures that the ladder is stable and secure while providing a safe working platform.