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Deceleration Distance:
The vertical distance between the user’s fall arrest attachment at the onset of fall arrest forces during a
fall, and after the fall arrest attachment comes to a complete stop.
Energy (Shock) Absorber:
A component whose primary function is to dissipate energy and limit deceleration forces which the
system imposes on the body during fall arrest.
Fall Arrest:
The action or event of stopping a free fall or the instant where the downward free fall has been
stopped.
Fall Hazard:
Any location where a person is exposed to a potential free fall.
Free Fall:
The act of falling before a fall protection system begins to apply forces to arrest the fall.
Free Fall Distance:
The vertical distance traveled during a fall, measured from the onset of a fall from a walking working
surface to the point at which the fall protection system begins to arrest the fall.
Harness, Full Body:
A body support designed to contain the torso and distribute the fall arrest forces over at least the
upper thighs, pelvis, chest and shoulders.
Horizontal Lifeline:
A component of a horizontal lifeline subsystem, consisting of a flexible line with connectors or other
coupling means at both ends for securing it horizontally between two anchorages or anchorage
connectors.
Horizontal Lifeline Subsystem :
An assembly, including the necessary connectors, comprised of a horizontal lifeline component and,
optionally, of: a) An energy absorbing component or, b) A lifeline tensioner component, or both.
This subsystem is normally attached at each end to an anchorage or anchorage connector. The end
anchorages have the same elevation.
Lanyard:
A component consisting of a flexible rope, wire rope or strap, which typically has a connector at each
end for connecting to the body support and to a fall arrester, energy absorber, anchorage connector or
anchorage.
Lanyard Connecting Subsystem :
An assembly, including the necessary connectors, comprised of a lanyard only, or a lanyard and energy
absorber.
Personal Fall Arrest System (PFAS) :
An assembly of components and subsystems used to arrest a person in a free fall.
Positioning :
The act of supporting the body with a positioning system for the purpose of working with hands free.
Positioning Lanyard:
A lanyard used to transfer forces from a body support to an anchorage or anchorage connector in a
positioning system.
Qualified Person :
A person with a recognized degree or professional certificate and with extensive knowledge, training
and experience in the fall protection and rescue field who is capable of designing, analyzing, evaluating
and specifying fall protection and rescue systems.
Self-Retracting Device (SRD):
A device that contains a drum wound line that automatically locks at the onset of a fall to arrest the
user, but that pays out from and automatically retracts onto the drum during normal movement of the
