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The fall guy

22 Nov 13 Access hirer Gordon Leicester has developed a new type of harness that could prevent a little-known but potentially deadly risk.

It is said that the romantic poet Samuel Taylor Coleridge got the inspiration for his epic poem Kubla Khan from a dream he had after taking too much opium. Gordon Leicester’s drug-induced inspiration was gifted by the altogether less romantic medium of Valium.

It was after having taken the painkiller on a flight from Italy that Leicester, managing director of powered access specialist Facelift, found himself almost literally dreaming up the idea for new type of fall-arrest harness. The unique claim to Leicester’s concept would be that the harness design would bring the victim’s legs upwards towards their chest as they fell. To understand why ending up hanging in a seated position rather than upright can give vital protection to the faller from height, and potentially save his life, it is first necessary to enter the slightly queasy world of the problems of suspension.

Suspension trauma is an unpleasant side-effect of having your fall arrested by a safety harness. It’s not something you hear much about – probably because those likely to suffer it are more focused on thanking God that they’re still alive than complaining about any injury they may have sustained. But when any fall-arrest harness does its job – preventing someone from falling from height to the ground – by its very nature it could leave the victim hanging for a period of time. And that can be nasty. Thankfully, after most such incidents the victim is brought safely down to earth without suffering too much apart from shock bruising. However, if that victim should have the misfortunate to be left dangling, they then risk doing themselves doing some serious mischief. After only ten minutes, long-term damage can result. Not surprisingly, Leicester has acquired a good grasp of the perils of suspension, which he describes in blunt terms: “Firstly, being left hanging with a groin strap could damage your testicles; then, because the heart is not strong enough to pump blood round your body when you are not upright, you could risk a stroke.”

Leicester’s harness specialist, Paddy Orrell, adds that this element is pretty well-known medically. “The reason that you have the phenomenon of guardsmen fainting on parade is that they haven’t moved their legs to keep the blood circulating. The same principle applies if you are left suspended, because you are left unable to move the legs to promote the circulation.” This results in blood ‘pooling’ in the legs, the first signs of which are feelings of light-headedness, numbness and nausea.

But further problems occur if the suspension is prolonged for more than ten minutes, and they can be made worse after the rescue – because then the pooled blood circulates again, either risking a clot, leading to a heart attack or a stroke, or risking the delivery of toxins to other organs, such as the kidneys or liver. But both of these problems typically occur days later, with the result that any connection to the original accident often never gets made, Leicester notes. If this all sounds a bit extreme, a Google search of ‘suspension trauma’ will confirm the medical basis - along with plenty of grisly tales of mountaineers. The fundamental problem of researchers being unable to hang a healthy person from a harness for extended periods means that there remains quite a lot of controversy about the subject - particularly the precise way to rescue someone after they have been suspended in their harness. According to the latest advice from the HSE, the sufferer should be laid out horizontally, not in any kind of ‘legs-raised’ position.

The HSE is also very clear that work from height should be planned so that workers aren’t actually put at the risk of being left danglng: “It is not acceptable just to rely on the emergency services.” However, if a fall does happen, the Executive stresses the urgency of rescue: “The key is to get the person down safely in the shortest possible time and before the emergency service response. If employers cannot do this, then harness work is not the correct system of work.” Given all that, Leicester (pictured below) says his intention was to design out the risk of the nasty stuff ever occurring, while at the same time eliminating the more common risk of groin strain. His idea was a harness that, rather than taking the weight at the groin, is instead connected to the legs. As the victim falls, the harness pulls the legs up arresting the fall while maintaining the circulation, thus preventing both impact trauma and suspension trauma. He also wanted a design that could be integrated into the user’s workwear. “I wanted to design something that was comfortable to wear, that you would just put on in the morning when you started work,” he explains.

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And to put his money where his mouth is, Leicester (having designed a prototype he was satisfied with) then jumped off a 2.5m-high access platform in his back garden and videoed himself hanging in mid-air for several minutes, then put the results on YouTube. Of course, given that it is such an essential piece of safety equipment, it will come as a relief that this ad-hoc exercise is not the only test the harness has been subjected to. First it was taken to the Health & Safety Laboratory in Buxton, where it was tested against four conventional harnesses. Then it was independently assessed by the University of Brighton at the Millbrook test labs, which is where carmakers crash-test their vehicles. The result of a test drop from a height of 4m was that the force exerted on the harness was significantly reduced compared with conventional harnesses - 0.86 tonnes, compared to 1.2 tonnes for a rear-attached conventional harness and 1.6 tonnes for a front-attached version.

The ZT (Zero Trauma) harness has also been independently certified to bear a weight of 150kg. This is a full 50kg more than the load allowed for under the relevant standard EN361 and for which many harnesses are designed, says Paddy Orrell: “We think that many construction workers are going to be heavier than 100kg, which is only 15 stone.” The key to the ZT design is a set of webbing straps that run from the body down each leg and are anchored to a patent ‘gaiter’ at the calf. Each gaiter (pictured below) has six laces which, when the worker falls, first enclose the calves then automatically pull the knees up to the chest. Whilst they are called laces, they are in fact individually threaded and stitched cords, rated to a load of half a tonne, so there is no chance of them breaking.

But the design is not the only distinctive thing about the ZT. As something of a serial entrepreneur Leicester reasoned that there was no point inventing something unless he could control the production processes himself. So not only did he set about the design, he also brought the manufacturing to the Facelift HQ at Hickstead. The result is that behind the hire depot at Hickstead there is now the ZT Safety Systems harness factory.

The unit looks not unlike a garment factory, featuring a team of machinists sewing (except these are computer-controlled sewing machines, more commonly used to stitch car airbags, and the stitching is industrial strength) as they turn metres of webbing into ZT harnesses. The scale is not industrial – not yet anyway – but at capacity the workshop will be able to produce 350 harnesses a month. The last 18 months have seen Leicester and Orrell taking the harnesses to potential blue-chip customers, with a policy of doing live demonstrations, which they believe, given the radical design, is the best way of convincing people. The policy is paying off, with interest from some major potential users including BAM Nuttall and Network Rail, and orders winging their way to a distributor in Australia. Because the design of the ZT enables it to be sewn into the workwear, it enables a customer to specify it for their own uniforms – another added benefit for the corporately-minded, Orrell believes. Both men are convinced that the message – particularly for men - is a compelling one. Leicester puts it succinctly: “You just have to ask yourself: What price are your bollocks?”

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