What is one method to ensure safety in a trench or excavation?

One effective method to ensure safety in a trench or excavation is to slope the sides to the angle of repose. This technique involves altering the trench's walls to a safe incline, taking into account the soil type to minimize the risk of collapse. The angle of repose is the steepest angle at which loose material remains in place without sliding or falling. By sloping the sides, the structure of the soil is more stable, significantly reducing the potential for accidents and ensuring worker safety during excavations.

Other methods might support safety but are either less effective or not proper safety practices. For example, while using ladders allows workers to enter and exit safely, it does not address the inherent risk of trench wall collapses. Similarly, filling a trench with water can introduce hazards such as drowning or difficulty in escape. Painting the sides of a trench may improve visibility but does not contribute to structural stability and does not ensure safety in the event of a collapse. Sloping thus stands out as the most practical and preventative measure among the options presented.