Fall arrest is of two major types: general fall arrest, such as nets; and personal fall arrest, such as lifelines. The most common manifestation of fall arrest in the workplace is the Personal Fall Arrest System, or PFAS ("lifeline").
Such a system should include 5 elements referred to as ABCDs of Fall Arrest:
A – Anchorage – a fixed structure or structural adaptation, often including an anchorage connector, to which the other components of the PFAS are rigged.
B – Body Wear – a full body harness worn by the worker.
C – Connector – a subsystem component connecting the harness to the anchorage – such as a lanyard.
D – Deceleration Device – an essential subsystem component designed to dissipate the forces associated with a fall arrest event. It is good practice and recommended that these are also included in Restraint systems, in case of foreseeable mis-use.
E – Emergency Plan & Equipment – a clear and simple approach to rescue of a suspended worker following a fall arrest event. All workers should be familiar with the site specific plan and competent to implement it. If a suspended worker is not recovered in good time, they may suffer the potentially serious effects of "suspension trauma".
Each of these elements is critical to the effectiveness of a personal fall arrest system. There are many different combinations of products that are commonly used to assemble a personal fall arrest system, and each must meet strict standards. The specific environment or application generally dictates the combination or combinations that are most appropriate.