Safety Trained Supervisor in Construction (STSC) Practice Exam 2025 - Free STSC Practice Questions and Study Guide

The correct answer indicates that the recommended horizontal distance from the base of a straight ladder to the vertical plane of support is 1/4 the ladder length. This guideline is based on principles of stability and safety when using a ladder.

When a ladder is placed at this distance, it forms a safer angle against the support structure, ensuring that the ladder does not tip over easily. A distance of 1/4 the ladder length provides a balance that helps to distribute weight and reduces the risk of falling while ascending or descending. This placement enhances the overall stability of the ladder in relation to the surface it leans against, minimizing hazards associated with improper ladder setup.

In contrast, the other options suggest different ratios that do not adhere to safety best practices. For instance, a distance that is only 1/2 or 1/3 the ladder length may create a steeper angle, which could lead to a higher risk of slipping or tipping over. On the other hand, using a distance equal to the ladder length would make the ladder excessively diagonal, likely causing instability. Thus, adhering to the guideline of 1/4 the ladder length ensures that safety is prioritized while effectively allowing for safe use of the ladder in various applications.