Working at Height
The Number 1 Oversight when working at height
Too often Leading Edge trainers check out work sites only to find individuals doing work at height making the same blunder often.
Is this a minor mistake? Basically no! It is one that would be disastrous if the operative fall.
Most people are convinced the number one mistake being a worker working without having safety gear. Not so!
The number one error Leading Edge trainers observe is when businesses have incurred the cost of providing safety equipment, however through insufficient the necessary awareness the actual worker is employing it incorrectly. The worker appears safe but does not realize that if he falls his protective equipment will fail.
It would be a tragedy, worse it would be avoidable.
The number 1 error is actually connector incorrect use by the site worker.
Exactly what does incorrect use mean?
1. Choking - tying off inappropriately
2. Connecting to an unsuitable anchor point
3. Inappropriate directional loading
This is when a site worker is provided a lanyard, often with a small karabiner at the end. The site worker intuitively passes the lanyard around an anchor point e.g. some sort of column or perhaps a beam, using the actual karabiner to choke i.e. tighten up the actual lanyard around the anchor point.
However, the problem arises should the worker fall, further tightening up the actual choked lanyard and consequently applying a shock load inappropriately to the karabiner gate more than likely resulting in the barrel of the karabiner to fail.
Karabiners are created to allow tensile (pull) forces along their length consequently they are at their weakest if the load forces are across the minor axis (width) or against the gate.
It is usually recognized that in order to engineer a connector to withstand the directional loading across the gate of the Karabiner which has been choked in the course of a fall would require a gate strength of 5,000 lbs.
Note that this particular dynamic loading failure across the gate of the connector is applicable to all styles of connector i.e. scaffold hook, snap hook, and karabiner.
2. Connecting to an improper anchor point
For example, a roof worker could possibly intuitively connect to an handrail believing this to be a appropriate fixing point.
Notice! All temporary anchorage points have to have the ability to withstand a 12 kN Load. If in doubt the particular anchor point needs to be approved by a structural engineer.
Leading Edge level 1 and 2 training covers identifying acceptable anchor points.
3. Scaffold Hooks
Scaffold hooks in many cases are placed around scaffolding resting on a horizontal member, i.e. the gate of the scaffold hook is going to be forced open subject to the loading that would be imposed by the horizontal member during a fall. This happens because the downwards direction or loading imposed by the cross-member across the axis of the gate on the scaffold hook plus can lead to 100 % hook failure since the hook gate is going to subsequently flex open, or perhaps in worst-case scenario, may burst.
Overview of connector improper use
Frequently a lack of understanding of equipment performance and its particular limits may lead to site workers getting supplied with the wrong safety gear that is unsuitable for its intended use.
For example the scaffold hooks in many cases are chosen the place where a sling would have been a a lot safer option.
Finally this section about wrong use associated with connectors, which will have devastating and in some cases deadly outcomes; it is very important for any site supervision, Foreman and stores personnel to be qualified to be able to issue the appropriate equipment for the job.
Site operatives, generally because of lack of instruction are not aware of the things they are able to do using the simplest of products such as connectors. It is therefore necessary that both site workers and those managers responsible for height safety are adequately trained to be proficient to execute their duties safely.
Connector misuse is just one of twenty five or even more total equipment improper use areas leading edge frequently see on site.
Death to the number 1 mistake - not the site worker
The way to select and use connectors
Many years of practical experience on site has persuaded us at Leading Edge that the solution dependes in the following:
1. Adequate strength and load-bearing functionality
2. Right size
3. User friendly
4. Light and portable to carry
5. Commercially suitable
6. Getting properly trained to work with connectors along with related equipment
Inevitably this usually leads back to specifying slings, be they webbing or cable.
These types of proprietary products need to be PPE products which are CE accredited, which is designed to be an integral component within any kind of fall prevention system and not a bit of wire which somebody has terminated.
Slings fall under two categories
Wire -cable sling to EN795
Often a 1m (but can reasonably be any length) galvanised steel cable, in a very hard but flexible type resin jacket, so that it is more resilient from abrasion as well as corrosion, also protecting the anchorage point from cable abrasion. This type of configuration is commonly used along with inertia reels.
Webbing slings to EN795
This is usually a product which can be light-weight and easy to carry around, that contributes to its attraction which is relatively inexpensive. It is sometimes used when anchoring to a scaffold pole.
Proper utilization of scaffold hooks and karabiners
It could be the situation that it is easier to tie off with a scaffold hook than a sling and standard karabiner, but a scaffold hook is made to be suspended off horizontal Anchorage e.g. of a horizontal scaffold tube, providing appropriate directional loading (vertical downward load).
As stated earlier karabiners are usually weakest when they are loaded across or against their gate.
This means that it is vitally important that the karabiner is at all times loaded along its length and not across its width, which would pull against its gate or cause the karabiner to take a force against the gate. So make sure you take care
fall arrest products
The Number 1 Error Using Fall Arrest Equipment
Author: Drew Beardmore
Leading Edge Working at Height Safety training courses and Fall Arrest Equipment are specifically designed for anyone whose job requires them to work at height and involves using the necessary safety equipment required to do this.
For more information visit www.leadingedgesafety.co.uk