harness and a self-retracting lifeline, shock-absorbing lanyard or other deceleration
device designed to bring a falling user to a stop in the shortest possible distance while
limiting the force imparted to the user’s body.
2.6: Fall Restraint
Fall Restraint
is an area of Fall Protection devoted to restraining the user of the
system in a manner which restricts his or her access to the fall hazard in a manner such
that they cannot be subjected to a fall. A typical Fall Restraint System consists of an
anchorage, a full body harness or a restraint belt and a restraint lanyard. A Shock-
Absorbing Lanyard or a Self-Retracting Lifeline should never be utilized in a restraint
application as it they not capable of restricting a user’s access to fall hazards.
2.7: Work Positioning
Work Positioning
is an area of Fall Protection devoted to allowing a user to work on
a vertical surface by means of a positioning assembly, and restricting the user’s
exposure to a fall of no more than two feet. Typical positioning assemblies consist of a
large rebar hook and a length of chain, rope, wire rope or webbing with a double locking
snap hook on either end. These snap hooks are attached to d-rings on the hips or on
the waist of the user’s full body harness, with the rebar hook attached to the structure
upon which the user is working. An
SAL or an SRL
should never be used for work
positioning, nor should they ever be attached to a side or hip d-ring on a full body
harness.
However, while rigged for work positioning, the user should always have
an SAL or SRL attached to the back d-ring of their full body harness and tied-off
to the structure on which they are positioning as a back up device
.
2.8: Free-Fall
Free-Fall is the distance that a worker will fall before the connecting device or
deceleration device elements of the PFAS will begin to engage during a fall event.
OSHA allows a maximum Free-Fall Distance of 6’ (6 feet) when rigging a Personal Fall
Arrest System (PFAS). In some cases, exceptions may be allowed when there is no
practical way to limit the Free-Fall Distance to 6’, such as a job-site where no overhead
anchor-point is available. Tying off in a manner that would create a Free-Fall greater
than 6’ should always be a last resort. If you are rigging a system that allows more than
6’ of Free-Fall, make sure your Connecting Device/Deceleration Device is rated for this
application.
2.9: Clear-Fall
Clear-Fall or Clear-Fall Distance is the distance that is required to safely arrest the
fall of a user. When working at heights and using a PFAS, it is important to consider the
distance between the walking/working level and the next lower level to ensure that the
components selected are capable of arresting the user’s fall before they hit the next
lower level. The required Clear-Fall Distance can easily be calculated by adding
together the Free-Fall Distance, the Deceleration Distance, the height of the user plus a
safety factor of 2 feet. The formula for calculating Clear-Fall Distance is shown below:
Free-Fall Di Deceleration Di Height of Safety Factor =
Clear-Fall Distance
The matrix below can be used as a guide for calculating Clear-Fall Distance on your
job-site:
Example Values
Actual Values
Free-Fall Distance
(OSHA allows up to 6’)
6’
Deceleration Distance
(Typically 3.5’ or less)
3.5’
Height of Worker
6’
Safety Factor
(Minimum of 2’)
2’
Total
(Sum of all values)
17.5’
