When climbing a ladder, you must maintain three points of contact at all times. This means having either two hands and one foot or two feet and one hand in contact with the ladder. This rule ensures maximum stability and safety, reducing the risk of slipping or falling. The three points of contact help keep your balance and control as you ascend or descend the ladder, and it's important to move slowly and deliberately while maintaining this contact. This rule applies both when climbing up or down and while working on the ladder.