Petzl Stop Poll

[dunc]

Don't worry about the "licence to cave" idea putting lots of people off `cos it's never going to happen

It practically has anyway cus you're not allowed to alot of places without insurance, of which you need to be a member of club/bca (thats close to a licence) - that along with permits (which the average non-caver can't understand) helps put people off anyway.

I find holding the handle on a Stop for any length of time quite fatiguing and ultimately painful.

I've never had a real problem with that - only on a few odd occasions on the the big pitches, which, lets be honest the uk doesn't have many of!

 

[Andy Sparrow]

your expression about the Petzl Stop being "counter intuitive" rings a bell - it's been one of Andy's observations about the device for a long while

Not actually my quote. 'Alpine Caving Techniques’ by Georges Marbach and Bernard Tourte has been the standard reference work for caving techniques in Europe for over 20 years but has only recently been translated into English. On the subject of descenders it offers the following opinions:
“The normal spool descender [bobbin or basic] is the most widely used in Europe, and we especially recommend this model to the beginner.”
“Auto-lock descenders [Petzl Stop type] are like normal descenders with an automatic stopping mechanism. This works by releasing the handle, while the descent is made by holding the handle down. This is counter-intuitive and can lead to significant injury (or worse) if a novice panics and automatically grabs hold of the descender and handle; auto-lock descenders should therefore be reserved for experienced vertical cavers.”

STATISTICS

UK These are taken from BCRC reports from 1995 – 2004 which can be found at
http://www.managerie.co.uk/bcrc/bcrindex.htm
The total number of incidents for this period is 479. There are 11 incidents described as ‘lost control abseiling’. It does not specify if these are all Stop descenders but I am advised by CRO members that this has been the case with all such incidents in their region. The Derbyshire incidents were described in Descent magazine as being Stop related. In addition to these incidents but not included in the total is a training tower accident that caused serious injury.

FRANCE
This information was kindly supplied by Jean-Paul Couturier from the records of Speleo Secours (cave rescue) France. He tells me that the average number of rescues is around 30 per year in 1995-1999 and only 18-20 each year during 2000-2004. This suggests a total for the ten year period of 245.
Loss of control abseiling accidents for this period were:
With the Basic descender: 3
With the Stop descender: 6
Jean Paul also tells me that there are an estimated 14000 cavers in France and that, by his estimation, two thirds of them use the Basic. The Basic is promoted by the French national body (FSS) for the reasons outlined in Alpine Caving Techniques.

 

[dunc]

With the Basic descender: 3
With the Stop descender: 6

Whilst the Stop has twice the number of incidents in France as the basic it isn't many over 10 years - ok, there should be none in reality but we don't live in a perfect world and no amount of training will remove all incidents.

Going on the above why pick on the Stop when there were 3 incidents involving non-stop descenders? Perhaps better training and information for abseiling techniques for all descenders would be better..? Admittedly the Stop has a greater problem factor than other descenders but the others aren't without fault when used incorrectly either...

 

[dunc]

There are 11 incidents described as ‘lost control abseiling'. It does not specify if these are all Stop descenders but I am advised by CRO members that this has been the case with all such incidents in their region.

I thought (if I'm wrong please correct me) that the unfortunate incident 17/1997 was the result of a rack problem...??

 

[Andy Sparrow]

I thought (if I'm wrong please correct me) that the unfortunate incident 17/1997 was the result of a rack problem...??

Yes, that's correct but it's not included in my figures. The 11 were all 'lost control abseiling'; the Lancaster Hole incident did not fall into that group.

 

[Andy Sparrow]

Going on the above why pick on the Stop when there were 3 incidents involving non-stop descenders?

According to Jean-Paul two thirds of French cavers use the Basic. The fact that the Stop has double the accident record seems to me to be quite significant. It also suggests that the approximately 9000 French cavers using the Basic experienced only three loss of control accidents in 10 years.

 

[andymorgan]

If you are a Petzl Stop user please spend a minute to help with this poll. .

I voted trained on surface advised by another caver. We had a small set up off a bridge about 3m which allowed us to practice changeovers while being advised from above and below. I used one for the first time underground last weekend again being advised when I was going down the rope from above, and someone to watch me on the (easy) rebelay.

Question 2: Were you made aware during your training that the Stop had a bad accident record?

No, but I was told that abseiling is possibly the most dangerous part of SRT as you only have one point of attachment. I was taught to use it with a braking karabina, and to control the speed of the descent with the free end of the rope rather than the handle, and under no circumstances to let go of the end of the free rope until you are locked off. (I suppose using it like a bobbin)

 

[MSD]

Key piece of data missing - presence or absence of a braking carabiner for those casualties using Stops. A braking crab is pretty much mandatory using a Simple, but I have seen many people abseiling using a Stop with no braking crab. It might be that part of the problem lies there.

 

[darkplaces]

Back to training again and the closed caving group system... As one french policeman said, "You pay me now!" with regards to club fees and insurence.

Round and round in circles we go.. Its Training Stooopid... The open spread of information. The actual number of people seriously using SRT is not very high and people are not keen to teach incase something happens and they get blamed.

 

[cap n chris]

It practically has anyway cus you're not allowed to alot of places without insurance

Hmm, Peak Cavern, Dan-yr-ogof & Gough's Cave spring to mind. Where else are you thinking of?

 

[Andy Sparrow]

people are not keen to teach incase something happens and they get blamed.

Do you think so? Anyone out there refusing to train SRT because of this concern?

 

[paul]

Secondly on "clutch and plummet" type accidents - how prevelent are they? It actually seems quite counter intuitive to me - to grip for dear life - I actually find it quite a bind holding the handle on a stop in on descents...(or am I just lazy!!!)

I believe that the problem lies mainly with new users of Stops (or any other auto-lock descender) who have no previous experience of using descenders.

If you are dangling from a rope using a non-auto-locking descender (Bobbin, rack, figure-of-eight, sticht plate, chained krabs, etc., etc.) you soon learn the direct relationship between gripping and controlling the end of the rope below the descender (the "loose" end as described previously) and the speed of descent. Most will begin their first descent gripping as hard as they can to the rope above and below the descender which is the natural reaction when hanging over a drop. You realise that gripping is good as you hang there not moving!

With an auto-lock descender, the user who has never used a descender before naturally feels very anxious dangling above the same drop. But the user has no real mental connection between how gripping the rope below the descender will prevent catastrophy as they are patently not moving while they dangle because the descender is auto-locked. They tentatively remove one hand, then the other - they don't move (or the descender creeps slowly down the rope). They feel safe and in control.

OK - now they know that moving involves pressing the red handle in, so they do so. They hopefully grip the rope below the descender and press the handle. The natural reaction is to then lessen the grip on the handle as this beginning to move is a bit frightening! That seems to work and instead of using the other hand to control descent, they have a loose grip on the rope and tend to use the handle to speed up and slow down. They have to be told to keep the handle in and use their controlling hand to control the descent.

If for some reason they then go too fast (say they hot a glazed section or a wet section on an otherwise dry rope), there is no automatic reaction to let go of the handle and having not had experience of controlling descent using the free end of the rope, they probably haven't the time to realise what needs to be done (i.e. grip the rope harder or pull it up against the braking krab) before they hit the deck.

Personally I believe that it is better to become experienced at using an auto-lock descender with the auto-lock function disabled (e.g. by using a krab in the hole for that purpose on a Stop) or by starting with a Bobbin or Simple. Of course a braking krab should always be used (as Andy S. has pointed out previously, Petzl say the Simple or Bobbin should always be used with a braking krab and a Stop should always be used with the handle held in all the way - which is then no different then from a Bobbin!).

Once adept at using the auto-lock descender as a normal descender with the auto-lock function disabled, the function can be restored by removing the krab from the hole and then practice using the auto-lock function.

 

[Mine Explorer]

Back to training again and the closed caving group system... As one french policeman said, "You pay me now!" with regards to club fees and insurence.

Round and round in circles we go.. Its Training Stooopid... The open spread of information. The actual number of people seriously using SRT is not very high and people are not keen to teach incase something happens and they get blamed.

Do I detect someone trying to shift this thread to suit their own personal agenda?

The techniques of SRT are hardly a closely guarded "club" secret. There are books on the subject and even web sites describing the various manoeuvres. Whilst I wouldn't suggest someone learns SRT from a book, the information is out there.

For a more practical guide to learning SRT for someone who has a vendetta against caving clubs there is the option of various commercial training courses, and not forgeting the rope access training route as well.

For people with an open mind, contacting a local caving club can be a cheap, easy (and if done correctly, safe) way to be introduced to vertical exploration.

I can't speak for other clubs, but we don't stand over someone with a membership form before taking them underground or introducing them to SRT. If the person concerned comes back for more and has an interest then understandably we will suggest they join the club - one benefit is that the club knows the location of all holes in our local area and knows what access conditions the landowners impose. In some cases we purchase a license from the landowner, in others we are issued with keys. Some require a written request at least a month in advance (that's to a land owner - not a caving club). Yet more, we know who to telephone before we visit. Some are open, some are gated, some are securely fenced - the landowner gives us a bucket of fencing staples and the tools, and asks us to leave it as we find it!

As for insurance - the club decided it would be a requirement of membership, and not an onerous one at that. For the majority of places we visit we don't need it, but when it is necessary it's available. A number of the landowners in our local area only allow access because we have insurance - of course it doesn't stop other people visiting those places without insurance, it's just they haven't asked for landowner permission, and as such are trespassing!

If the club is teaching someone SRT then it isn't the trainee that needs insurance - it's the person teaching them! The insurance scheme isn't for personal injury, it's third party. The chances of someone learning SRT injuring someone else to the extent they make a claim is (I feel) fairly slim. The chances of someone learning SRT getting injured and wanting compensation is slightly higher (although given good training technique, also very slim). Whilst teaching the club always has a second dynamic safety line in place for when the trainee decides to do what's easiest rather than safest! As already mentioned, we always teach using the rack before introducing the basic, then finally the stop. This introduces the idea of controlling descent with the tail-rope and not the handle.

 

[danthecavingman]

Morning all,

I think I posted somewhere already that I don't really like Stops. I learnt to use one being trained professionally for my IRATA level 1 several years ago. Getting used to using two ropes actually put me off caving for a while - that may sound a bit crap but I got used to having two ropes and all the back up that goes with it. Anyway, back to the topic in hand, I do not use a stop for caving as I find them to be unreliable and unpredictable on different rope types and conditions. I am now back into caving and getting used to SRT again, it is a bit of a hangover from IRATA but I now use a rack in conjunction with a shunt. Ideal for rigging and also gives me a chance of stopping if anything goes wrong during a descent. I have used a rack throughout my caving career and will continue to do so. I do have a Stop in my kit bag, as for rescue purposes it is invaluable.

Dan.

 

[Cave_Troll]

we are fortunate enoguht to be able to find good above ground traiing venues.
We can have mutiple people up on the ropes at any one time and they will all have 1:1 supervision. may be 1:2 supervison if they have demonstrated some abilty
This supervisoon rotates and people learn different things(ascending, descending, changing over, rebelays, deviations, pitch heads, horror stories, personal responsibility, shock factors blah blah blah) form different people. range of kits are available and we try to get them to use stop and rack.
Belaying on ladders, rescue, improvisation and "non standard" techniques liek ropewalking can also be covered.
so yes there are still people in the club system teaching SRT.
I agree that the trainee does not need the insurance, EXCEPT, that it is possible that if they drop something or kick a rock or totally ignore instructions in front of witnesses that is showing a blatant lack of care for their colleagues that it might be their fault someone gets hurt

 

[rich]

FRANCE
This information was kindly supplied by Jean-Paul Couturier from the records of Speleo Secours (cave rescue) France. He tells me that the average number of rescues is around 30 per year in 1995-1999 and only 18-20 each year during 2000-2004. This suggests a total for the ten year period of 245.
Loss of control abseiling accidents for this period were:
With the Basic descender: 3
With the Stop descender: 6
Jean Paul also tells me that there are an estimated 14000 cavers in France and that, by his estimation, two thirds of them use the Basic. The Basic is promoted by the French national body (FSS) for the reasons outlined in Alpine Caving Techniques.

Even if the estimate is accurate, what proportion of Stop users are novices? If newbies are more likely to use Stops (as over here), then this would skew the statistics, and would not necessarily indicate that it is equipment choice that is the problem.

 

[cap n chris]

Just like to say that this thread is proving tremendously readable.

 

[MSD]

The French statistics make interesting reading, but as Rich points out there could be various forms of bias which obscure the actual effect. Another problem is that the number of accidents which occurs is very small from a statistical perspective. 3 accidents vs 6 accidents is never going to yield a statistically significant conclusion.

So....I think we need to persue other ways of testing Andy's hypothesis. Ways of doing this:

a) via a longitudinal study of two groups of (initially) novices. Half are trained with stops, the other half with bobbins. The subjects are asked over a period of months/years after training to record details of all trips and report any "near-misses" where they have felt that they could have lost control, or other problems they encountered. This is of course a subjective notion and it would be desirable to define a "near miss" as rigidly as possible.

b) Through a detailed study of a number of novices, again in groups using different descenders. After initial training the novices would be asked to complete a number of set tasks - for example abseiling at a constant velocity, performing an "emergency stop", stopping at a given marked point on a rope, abseiling on a thinner rope than initially used during training and so on. Videos could be made for detailed analysis of how the people behaved. If necessary the exercise could be made safer by having a knot tied in the rope a few metres above the ground, to arrest a too-fast abseil in a reasonably gentle fashion.

I think these experiments, or perhaps a combination of them, would yield a lot of interesting information and give a useful basis for better training, more informed choice of equipment and hopefully less accidents. One difficulty is how to define "novice". Ideally they would never have abseiled before, but it might be difficult to find enough people in that category.

 

[Andy Sparrow]

Even if the estimate is accurate, what proportion of Stop users are novices? If newbies are more likely to use Stops (as over here), then this would skew the statistics, and would not necessarily indicate that it is equipment choice that is the problem.

This is a reasonable observation. It may be that the FFS training is all bobbin orientated and it is only untrained cavers who go against the trend and use a Stop. Statistics are useful but without going to the rather extreme lengths proposed by MSD they can only suggest trends.

What is apparent from the French figures is that their training program is effective in reducing accidents compared to UK cavers. I suspect that adopting the bobbin would reduce the UK accident rate but I think such a change is unlikely. What the poll reveals is that most cavers are trained by other cavers. The question is how do we train the trainer? Any suggestions?

 

[tubby two]

The question is how do we train the trainer?

By experience and peer evaluation. The people who do training are usually the more experienced members, who are generally accepted by other club members as suitable to guide and train novices.

Of course, i've not really answered the question, as this means the training people recieve is only the product of the experience and competence of other club members- hence being very very variable. Although proposing a liscence or qualification to train is akin to the qualification to cave- this is fine in a private guide scenatio (CIC's and that sort of stuff), but goes againt the whole tradition of caving and climbing and such sports, taught by experience.
The problem in climbing is the decline of the club culture, meaning more and more individuals are looking for private officially recognised training. I do hope caving never goes down this route though.
What could be valuable is a comprehensive resource on the web detailing recognised training stratagies for people who do informally train folk to look at and adopt new techniques as they wish. Is there not already something on the web like this- i know there are sites dedicated to srt techniques somewhere.
Maybe this is something we could get on here, a forum for people to discuss their preferred training methods so everyone else can see what they are doing and try out or adopt new techniques?


tt.