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ABCDs of
Fall Arrest
Personal Fall Protection for Material Handling Equipment
Materials handling
equipment
frequently gives rise to exposure to falls by operators and
maintainers of overhead hoisting systems., Provision for fall
protection and egress is needed where workers will foreseeably be
exposed to fall hazards.
According to the National Safety Council’s Accident
Prevention Manual, the approach to fall hazards should be as
follows:
• Recognition of each fall hazard including access
to the workstation;
• Control of the fall hazard through choice from a
variety of fall solutions;
• Selection and installation of fall protection
including engineering if required;
• Training sufficient to fulfill fall-protection
programs;
• Observation of workers and enforcement of fall
protection policies;
• Recognition of fall hazards could be as follows:
crane bridges, crane runways, ladders across to cranes, truss
access,
warehouse racks, platforms, operator cabs, access at heights, roofs
and mezzanines.
Fall protection measures should include the
following:
• Elimination of the hazard by reorganizing the
work;
• Prevention of falling by the use of
guardrails, including aerial lifts;
• Fall arrest systems for horizontal and vertical
travel;
• Warning lines six feet from an edge.
Fall arrest systems are often valuable when workers
overreach from aerial lifts, roof edges, climb fixed ladders or use
stepladders. In case of fire and smoke, listed controlled descent
devices may be beneficial in addition to fixed ladders typically
supplied according to NIOSH 76-128. These systems may also be used
for the rescue of individuals from height. Crane cabs and other
workstations are examples where installations may be made.
Training and inspection are vital for proper
application of a fall-protection. Workers should be given a pretest
and post-test to provide feedback to worker and manager alike.
Observation is vital to monitor the effects of site-specific
training. The training should cover regulations, standards, the site
conditions, the work to be done, the sequence of the work, the
materials, the work method, and fall-arrest equipment and its proper
use.
The fall protection for materials handling-related
applications must be applied at the very first thought about the
work and when other initial planning is undertaken.
ABCD
Every fall arrest system must include four elements,
often referred to as the ABCD’s 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: a subsystem component
designed to dissipate the forces associated with a fall arrest
event.
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 (ref 29CFR1910.66 appendix c). The specific environment or
application generally dictates the combination or combinations that
are most appropriate.
To arrest a fall in a controlled manner, it is
essential that there is sufficient energy absorption capacity in the
system. Without this designed energy absorption, the fall can only
be arrested by applying large forces to the worker and to the
anchorage, which can result in either or both being severely
effected.
Because fall arrest designs require high rate-energy
capacity design methods, fundamental fall arrest design is tedious
and esoteric. Thus, most fall arrest parts and systems are designed
to the force standards contained in Federal OSHA 29CFR1910.66
appendix c, a force-type design standard which accounts for required
energy considerations.
Actual loads on the user and anchor-anchorage vary
widely with user weight, height of fall, geometry, and type of
line/rope. Excessive energy into the support and user is avoided by
the use of energy absorbing PPE designed for the 1800 lbs maximum of
the referenced Federal OSHA standard.
The most common fall arrest system is the vertical
lifeline: a stranded rope that is connected to an anchor above, and
to which the user’s PPE is attached either directly or through a
“shock absorbing” (energy absorbing) lanyard. Once all of the
components of the particular lifeline system meet the requirements
of the standard, the anchor connection is then referred to as an
anchorage, and the system as well as the rope is then called a
“lifeline."
Anchors used for lifeline anchorages are designed
for 5000 lbs force per connecting user, and the standard permits an
anchor to deform in order to absorb energy (adhesive anchors have
higher design requirements because of aging loss).
FSM
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