Laz

Some very good points raised. But rather than talk amongst yourselves, join this discussion forum that is set up by HSE ESPECIALLY to hear from you (us): http://webcommunities.hse.gov.uk/inovem/inovem.ti/afagpublic/messageshowthread?threadid=1006 You will have to reg your email and a password, then Go to discussions. The common complaint from those at the top that can effect change, is they don't hear from enough grass roots to effect change. Please, get involved.

Thats how I tied mine, but with one extra wrap. You could run the pulley on a micro cord prusik. That way you can pull it down out of the way for Body thrusting. Just a thought.

Tim Sorry about the pics, but I'm afraid I had nothing to do with the photos or formatting - I severed ties with TV before the report formatting was completed. I agree some of the pics are not best presented. Its not me in any of the pics either (cause people often assume). That would be Richard Almond. Anyway, the Helical performed as well as any hitch in the tests. The testing showed that the philosophy that a double leg hitch is stronger than a single leg is flawed; when the hitch tightens enough to test the breaking strength, heat is generated which causes the braids to weld to the line. In the tests, this caused at least one VT hitch to fail twice during the pull before releasing the load. In comparison, one Blakes tied with 13mm single braid exploded at much lower loads. In fact, the wraps seemed to have vapourised, as only two straight sections of cord could be found. That was the strongest cordage used, but it didn't perform as highly. I made note of some specific insights during testing, that were never made public: After the report was completed, a meeting was held to discuss the findings and establish industry best practice. I wasn't invited because I was neither a verifier or a member of TV. Obviously doing all the research and word processing means I had nothing further to offer. It has always been my intention to write a summary of the research for the Arb journal with better graphics and photos to present the data in a more user friendly way.......... but no time or funding is available to me. Until then, based on the test results and cordage used, I recommend a minimum breaking strength of 1700Kg, polyester/ nylon, of double braid or kernmantle construction and 8-10mm diameter on 11-13mm lines, for all the friction hitches save the Blakes (thinner cords tend to bite too tight with this hitch). The success I had with tying the Helical, was to set the braids before tying the bowline, unlike your second photo.

Ha! I like the caveat Craig.....like I'm almost garaunteed to upset anyone at any moment! Tim I'd say the Helical is for you, tied with 10mm cord. The new ISC pulley looks like it was made for it. Don't ask me what its called - Judge will know, and I'm sure he'll supply it at a credit crunch worthy price.

You can say that about any knot, so my point is, the Helical is way more reliable than a VT. I have never found a VT as safe as a Helical, if fine tuning to attempt it to grip without question, yet release easily. This is because the Helical has the distinct advantage of being able to cinch up the Bowline once the number of braids and wraps are found that work with a specific system, so the slack can be adjusted to the millimeter. In comparison, the VT can loosen more, because the legs have no means to prevent them from separating. This makes the Vt able to advance easier, yet that advantage can easily turn into a serious safety concern by not grabbing when required. When competing against each other, Jon Hartill came up with the idea of running both legs through a small stainless steel ring to prevent the VT from separating away from the rope when released. We both moved on to the Helical. I'm not sure why Jon did, but I did for this reason. IMHO, setting up a VT to self tail is just asking for trouble - lightweight climbers can get away with it.

I disagree completely: IMHO The Helical is the safest of all the half hitch free prusiks. IF tied correctly, it can be fine tuned for the ultimate performance. In addition, because of the way it is tied, it can be set to any length. This makes it a great hitch for those wanting something to upgrade from a Blakes/Prusik performance.

I let this one slip, but actually looking at the draft I see huge potential problems for contractors using it as 'all works in compliance with BS3998'. I agree Linda that the EAC guide is much more useful as a guide and checklist for clients. I have tried to read BS3998 draft, but it is so complex, prescriptive and unbalanced, that I can no longer cross reference to it as a standard, and I can't even get to the end of it without falling asleep. If I cross referenced to that in a contract, it just gives the client too much opportunity to query some semantic detail and not pay up. Better to avoid all that altogether. The EAC guide at least highlights the main points such as use of spurs, risk assessment etc and recommends suitable qualifications - after all, the BSI standard reads like a level 3 qualification curriculum, and is totally unecessary because it could just as easily say 'All work should be supervised by a level 3 qualified and competent person'. Problem comes when it is promoted by industry or requested by clients. We wouldn't need such a standard if those engaged in tree work were required to be suitably qualified, supervised and updated. Again it shows how Chainsaw certs are insufficient as a measure of good Arboricultural practice.

There is always this risk on any harness - more so with load bearing leg loop designs. The answer is to 'adjust' yourself properly before tensioning the leg loops properly. I wouldn't recommend loose leg loops - always snug them up. I also recommend briefs over boxers. Leg loop harnesses allow proper articulation of the hip joint when working a crown. Hard seats are OK for hanging around for long periods.

Well that would be telling wouldn't it?

Just to clarify Tim: The TFX pelvic pad comes in three different sizes, to reflect the fact that the hip ds are set closer together or further apart depending upon size. The leg pads are the same size throughout. The webbing adjustment length is different on each size.

I ran about 60 drop and pulltests of arb systems using scaffold knots in a controlled environment with dynos. Not one issue. Have you ever wondered what might happen to a stitched eye if the shrink wrap is over heated? I've seen it a couple of times - the stitching melts but you don't see it. A friction splice pulled out on a Buddy of mine and he fell 35 feet. It was the ropes second day of use, and he is meticulous about safety. The point is, don't blindly trust to things. I will usually prefer to knot my lifelines for many reasons.

"So how would I know your harness was a good buy, should I just believe the salesperson without any proof?" Its what you have to do with every other harness, and with little understanding of the design team's credentials. Good luck - with your understanding of proper human use; we've explained enough about it over the past 5 years to know this isn't a good medium.

Lets just say I know how to get a point across. The comparison to IT sales and medicine aren't valid - they aren't high risk enough in terms of health and injury, and generally pay well enough (at least much better than arb) not to be a financial risk. Its not 'my' system, it is the prevailing system of arboriculture. The statistics prove it from our very own SSC. The conclusion is we are in crisis because of it. When I hear 'Career', it means undertaking an occupation for which we are well trained. The industry is in crisis because skills aren't being retained, because arborists aren't being trained - or at least well enough. By the time MOST climbers reach their 40s they (I know some of you are superheros who will never lie down and die) will move on from this industry because of physical injury or pain. Taking with them all of their acquired knowledge to be replaced by someone without relevant experience. If they studied hard and gained specific qualifications to augment their very important experience, that will enable them to give professional advice to the public, or industry. This is a cycle of increasing returns. And you don't need to be an academic! I am very pleased to hear of those who have said they committed to this industry, and had the good sense to do it properly by studying formally for academic qualifications and/or seeking a 3-5 year apprenticeship. Thats what this industry needs. Its a long road and the 'telligent tortoise beats the hare by a long, long way. Usually the hare cuts a leg on the way, meaning they rarely make the finish.

Quite seriously - Don't do it! There is little career with total committment. With the committment you can afford, you could be physically and financially sorry in 10 yrs time. And then what are you going to do? Have you got qualifications to fall back on? Are you going to keep on climbing everyday into your 50's? Or will you get pushed aside by the next young gun who will run round faster for less money until he burns up, to get replaced by the next young gun..... who will run round faster for less money until he burns up, to get replaced by the next young gun..... who will run round faster for less money until he burns up, to get replaced by the next young gun..... who will run round faster for less money until he burns up, to get replaced by the next young gun..... If they don't become another injury/death statistic first. Or maybe you'll break the cycle and set up in business, forced to undercut the competition and work faster and harder, employing climbers who will run round faster for less money until they burn up, to get replaced by the next young gun..... who will run round faster for less money until he burns up, to get replaced by the next young gun..... who will run round faster for less money until he burns up, to get replaced by the next young gun..... If they don't become another injury/death statistic first. Or maybe they'll break the cycle and set up in business, forced to undercut the competition and work faster and harder, employing climbers who will run round faster for less money until they burn up, to get replaced by the next young gun..... Its coined the cycle of diminishing returns by Jez Lawton, and is typical of this industry. There is no 'Career' in this game I'm afraid. Good luck.

Ha! Seems everyone forgot the weather caveat!

Just noticed I mentioned the Nobel peace prize - thats funny! It was of course the Nobel Prize for medicine, and the research was heavily relied upon in the Oration.

Hello Linda I've broken down my reply per paragraph below: “Laz, As well as a climber, I am also a scientist and an academic, and I am well aware of the dangers of misinterpreting or misapplying research results. I would not mention research on this site that was not of relevance to a particular thread or our line of work. Central to these particular research projects were not momentary forces exceeding x KN, but pressure as a constant upon bones/ligaments/muscles/nerves. Furthermore, the articles discussed several applications, including the work positioning area, which led me to believe it was highly relevant to our industry." REPLY - There is nothing good about sitting in a harness all day in terms of human bio-mechanics. There will always be risks. Especially for certain types of morphology. It is a question of what are the greater risks, and what are the best ways to mitigate them. This is where our paradigm differs (it seems) to others – including your initial post on the topic. "Misinformation you say, I say it’s important to look at issues from as many angles as possible. Why should I only look at information that is being fed to me through advertising where the male body is the norm? As we’ve agreed, in the end you are responsible for your own well-being and where you spend your money is your business." REPLY - I don’t recall stating misinformation. Rather mis-application. And yes, different angles are very important - Conceptual thinking is our natural style. "I would be interested in reading the research behind TreeFlex, has it been peer reviewed and published anywhere? Or could you pm it to me please?" REPLY - That would be very convenient for you but very inconvenient for us - Our knowledge is proprietary information reserved for the sole purpose of our clients. But it is based on principles and practice that is well established and predominantly ignored. Some of the scientific research and reasoning was heavily relied on for work that resulted in a nobel peace prize. Unfortunately, it didn’t lend itself to the powers that be, in a way that they could profit from readily – the status quo remains. That is changing as MSDs become more recognised as the single biggest factor affecting health, safety and general well being (occupational or recreational). "I agree with you Laz that assumptions are bad. The design of many so-called unisex harnesses available on the market today are based on the assumption that what works for men’s bodies will work just fine for women’s bodies as well." REPLY - Assumptions are bad, but too often in practical tree work, they are all we have to rely on, because of lack of funding and an inability of the trade associations to represent our best interests and secure public support – why would anyone want to invest in practical arboricultural research? Until they do, we will constantly have to assume, or seek free advice, or take the lead from certain personalities whom claim to know best. Credible advice can’t come free, because credible advice takes time and costs to acquire and insure. It is financial suicide to then give it for free. Even these forums require subsidising by advertising. Unfortunately, if we can’t earn, we can’t exist in a helpful capacity – we become the charity from being too charitable. This is a separate issue, that helps explain why the arb industry is in crisis. I think you credit the market too much that they think or assume at all about what works for any body. Nothing changed because it was a satisfactory market. There is great risk in stepping aside from the field that seems to be functioning perfectly well without having to invest in R&D. "Now for the first time we are seeing some changes to that mentality, largely thanks to the rising number of women involved in tree climbing competitions, both on and off stage, giving women in the industry a higher profile, making them “worth investing in”. REPLY - There is little change to the ‘mentality’. Yes, more women involved in arboriculture is a good thing. But the investment you speak of is purely marketing. It will apply itself to what women want. But that may have little to do with what women actually need. The tree climbing competitions are at least as far removed from real industry needs of women as they are for men. "The TreeFlex is part of this “new era” as well, although I myself am not sure you can actually have a harness that fits both men and women.” REPLY - In terms of effective arborist ergonomics, I’d say we pioneered the ‘new era’, rather than being a part of it. Emphasis on ‘effectiveness’. SRT is likely to become more popular, but already there is much evidence that it is being mis-applied in terms of effective physical ‘Use’. Your conclusions on harnesses may mean nothing more than not being aware of the principles of human ‘use’. This is because (despite prize winning work) ‘effective use’ of the human system isn’t taught on medical curriculums. Very experienced remedial fitness professionals do understand use, and are now being chosen to apply cutting edge scientific research, ahead of Physiotherapists, because of it. Good luck. Laz

You can do the same thing with the prusik on the right. Another good thing about the clove hitch is the way it is easy to adjust its position. If you fashion the anchor from your access line, you can take out the pulley too - just pull out the DdRT system and pull on the access line to retrieve. Thanks for re-posting that pic in this thread.

If I understand you correct with that idea of FS and krab, it will equalise, but if one anchor fails you'll shock load the other. These examples are exactly the same principle as the the pros and cons of trad rock climbing belay anchors. The middle prusik can be removed. Instead just clove hithc a krab where the prusik is tied to the red rope, and then clip it to the DdRT below. About as simple and safe as you can get. Or girth hich a ring. Good luck with the M. I'd prefer all the advantage of tying in to a totally separate system there, with my access line. Like I say, the anchor may be good, but if you sever one of the lines.... or if they get trapped, you can't escape without pulling up the end of the line and re-tying.

Hmmm........ Thinking about it, you could just clip the red rope the prusik is on through the prusik krab to get the same effect plus safety.

That was why I intially stopped using it; the size of anchor I'd feel comfortable with lead to too much friction. Especially round these parts - 4 inches of moss on the Oak boughs that seems permanently soaked.

That'll work Drew! Great pic. And its simple and versatile too. But in that pic, there is still an in-pull (probably necessary for the picture). By letting more slack into the anchor, and by using a shorter prusik, you get as safe and simple a system as I can think of. By using the access line, you can capture a fork from quite a distance. Cheers Laz

Be wary of using a re-direct above your main tip. It increases the anchor forces substantially. Especially with a rope guide as the main TIP and then a double pulley as the redirect. Better to tie in higher and back stay, or other techniques using the access line.

Its a very relevant point Dean. Climbing on TIPS as thick as a wrist is asking for trouble. Quite a few variables there that aren't considered. The single biggest issue of tree work safety, is usually having to work with one anchor, yet having no clue as to how strong it is. Pulling straight down, its amazing what will hold you, but start moving out and up, and it can be alarming what won't. A case in point that ties in with this discussion stateside: http://www.treebuzz.com/forum/showflat.php?Cat=0&Number=137641&Main=137455#Post137641 To take your point about a wrist size Dean, my wrists are pretty thick at 8 inches round, making them 2.5inches thick. That was the TIP that bust out in the thread. I prefer something in the region of 4-6 inches diameter, depending on species and the taper ( height over diameter ratio) of what I'm tied into. By that reasoning, I tie into something as thick as my forearm if all is well. Any uncertainty from a distant throw, and its 8" thick minimum, looking for a second crotch as back up (SRT).

I disagree on this Tom. Re-directs are used usually (at least by me) at the extremeties of branches; there is often a risk of a re-direct failing. But I don't worry about that, becuase I still have favourable swing angles. The potential swing can easily be controlled by belaying the line. The issue with the M is it compromises the primary anchor. That should never be encouraged. The idea of a secondary tie in is to reduce the risks of having just one; where is the logic and sound reason in compromising the effectiveness of the primary anchor to a potential freefall situation? There isn't any. Even if the anchors are bomb proof, there are other risks: There are now four strands of line branching out from the same point on the harness. If ANY one of those is cut, again, the climber goes into freefall. These scenarios are likely to lead to serious PERMANENT injury or death. Hard to justify that risk when its not even necessary to use the technique. Hell, I see climbers routinely tie in to too small a TIP all the time - I doubt they pay much attention with a secodary tie in either, probably because they think they still have the first to rely on. Thats my stand on it. I've explained the risks well enough, its up to each climber to understand them. Personally, I'm tired of climbers trying and dying when it just isn't necessary. It also threatens my insurance premiums and induces more legislation....... To be taken seriously as professionals, we have to improve safety and efficiency, not constantly chip away at them. Saddle up cowboys - ride on! Yehah!