Height Safety - The Number 1 Mistake When Working at Height

All too often our trainers visit work sites only to findworkers being issued with inappropriate safety
people working at height making the same mistakeequipment which is not suitable for its intended use.
again and again. Is it a minor mistake? No! It is oneFor example the scaffold hooks are often used
that would be catastrophic if the worker should fall.where a sling would be a much safer option.
Some people think that the number one mistake as aTo conclude this section on misuse of connectors,
worker operating without safety equipment. Not so!which can have devastating and even fatal
The number one mistake I see is where companiesconsequences; it is important for a site management,
have incurred the cost of providing safetyForeman and stores personnel to be competent to
equipment, however through lack of the requiredissue the appropriate equipment for the job.
knowledge the worker is using it incorrectly. TheSite workers, generally through lack of training are
worker feels safe but doesn't know that if he fallsnot aware of what they can do with the simplest of
his protective equipment will fail.equipment such as connectors. It is therefore
It would be a tragedy, worse it would beessential that both site workers and those managers
unnecessary.responsible for height safety are adequately trained
The number 1 mistake is connector misuse by theto be competent to carry out their duties safely.
site worker.Connector misuse is just one of 25 or more total
What does misuse mean?equipment misuse areas commonly seen on site.
1. Choking - tying off incorrectlyDeath to the number 1 mistake - not the site worker
2. Connecting to an unsuitable anchor pointHow to choose and use connectors. Years of
3. Incorrect directional loadingexperience on site has convinced me that the
1. Chokinganswer lies in the following:
This is where a site worker is supplied a lanyard,1. Sufficient strength and load-bearing capabilities
often with a small karabiner at the end. The site2. Correct size
worker instinctively passes the lanyard around an3. Easy to use
anchor point e.g. a column or a beam, using the4. Lightweight to carry
karabiner to choke i.e. tighten the lanyard around the5. Commercially acceptable
anchor point.6. Being properly trained to use connectors and
The problem arises should the worker fall, furtherassociated equipment
tightening the choked lanyard and subsequentlyInevitably this often leads back to specifying slings,
applying a shock load inappropriately to the karabinerbe they webbing or cable.
gate most likely causing the barrel of the karabiner toThese proprietary products have to be PPE items
fail. Karabiners are designed to accommodate tensilewhich are CE approved, designed to be an integral
(pull) forces along their length and are at theircomponent in any fall arrest system and not just a
weakest when the load forces are across the minorbit of wire which somebody has terminated.
axis (width) or against the gate.Slings fall into two categories
It is generally accepted that to engineer a connectorWire -cable sling to EN795 - Usually a 1m (but can
to withstand the directional loading across the gatereasonably be any length) galvanised steel cable,
of the Karabiner which has been choked during a fallinside a hard but flexible resin jacket, making it more
would require a gate strength of 5,000 lbs.durable from abrasion and corrosion, also protecting
Note that this dynamic loading failure across the gatethe anchorage point from cable abrasion. This type of
of the connector applies to all styles of connector i.e.configuration is commonly used in conjunction with
scaffold hook, snap hook, and karabiner.inertia reels.
2. Connecting to an unsuitable anchor pointWebbing slings to EN795 - This is a product which is
For example, a roof worker may instinctively connectlightweight and easy to carry around, which adds to
to an handrail believing this to be a suitable fixingits attraction and is relatively inexpensive. It is often
point.used when anchoring to a scaffold pole.
Note! All temporary anchorage points must be able toCorrect use of scaffold hooks and karabiners
withstand a 12 kN Load. If in doubt the anchor pointScaffold Hook
should be approved by a structural engineer.It may be the case that it is easier to tie off with a
3. Scaffold Hooksscaffold hook than a sling and standard karabiner, but
Scaffold hooks are often placed around scaffoldinga scaffold hook is designed to be suspended off
resting on a horizontal member, i.e. the gate of thehorizontal Anchorage e.g. of a horizontal scaffold
scaffold hook will be forced open subject to thetube, ensuring correct directional loading (vertical
loading that would be imposed by the horizontaldownward load).
member in the event of a fall. This occurs becauseKarabiners
the downward direction or loading imposed by theAs mentioned earlier karabiners are weakest when
cross-member is across the axis of the gate on thethey are loaded across or against their gate. This
scaffold hook and will result in complete hook failuremeans that it is vitally important that the karabiner is
as the hook gate will subsequently bend open, or inalways loaded along its length and never across its
worst-case scenario, will explode.width, which would pull against its gate or caused the
Summary of connector misusekarabiner to take a force against the gate. So please
Often a lack of understanding of equipmenttake care.
performance and its limitations can result in site