Two terms that commonly get mixed up are the concept of “fall arrest” and “fall restraint”, however they mean two very different things.
Fall arrest systems are used to slow or damp a fall when it occurs. They’re used in situations where a fall is likely, such as working at height on ropes or where a platform cannot be used. For example, an engineer climbing a tall building wearing a harness will have fall arrest equipment so if he trips (which is likely in these situations), they’ll come to a graceful stop and won’t fall too far.
Fall restraint equipment aims to stop the fall ever happening. The user is secured in such a way that fall becomes impossible. This is a preferred solution when working in situations where any fall would be dangerous.