What factor is essential when positioning portable ladders?

Base stability is crucial when positioning portable ladders because it directly impacts the safety and effectiveness of the ladder during use. A stable base ensures that the ladder maintains its position without sliding or tipping over, which can lead to falls and serious injuries. Properly setting the ladder on a level surface, using stabilizing accessories if necessary, and ensuring that the feet of the ladder are secure are all important aspects of achieving base stability.

While other factors like the angle of elevation and surrounding lighting conditions are important considerations for safe ladder use, they do not replace the fundamental necessity of having a stable base. Height extension, while relevant in discussing how high a ladder can reach, does not relate to its stability once positioned. Ensuring that the ladder is stable at its base is the primary factor that secures the user’s safety while working at height.