What angle should a non-self-supporting ladder be placed at for safe use?

For safe use, a non-self-supporting ladder should be placed at an angle of approximately 75.5 degrees. This angle is recommended because it strikes a balance between stability and reach. When the ladder is positioned at this angle, it ensures that the base of the ladder is securely placed on the ground, preventing it from slipping outward while providing enough height to safely climb and work from the ladder.

Using the 75.5-degree angle allows for the optimal distribution of weight along the length of the ladder, resulting in better stability and reducing the risk of tipping over. Moreover, this positioning minimizes the strain on the climber, making it easier to maintain balance during ascent and descent.

In contrast, an angle of 90 degrees would imply that the ladder is almost vertical, which could increase the risk of the ladder tipping over or becoming unstable. A 45-degree angle would make it challenging to climb as it doesn’t provide sufficient reach, and a 60-degree angle, while better than the alternatives, is still not ideal as it does not offer the same level of stability as the 75.5-degree angle.