When to use screamers

Well let me ask you this about that single old test everyone is quoting

Did they use a mechanical hand when on their tests to rule out the variability in the catches?

If not were the catches double blind and randomized, by the same person i assume?

How many runs of each of the listed circumstances were performed? Ie sample size?

Was a brand new section of rope used for every of the said tests, i would assume so?

Have they been repeated by others?

These are all basic questions that i want answered when marketers used to come up to me and claim their marketing test prove their awwwsummness ... That was selling useless junk to suckers, this is "life and death" so the standards should be higher ;)

dont use it where it the extension can cause a grounder ... other than that, use if it you want ... or dont

its like god ... believe in him if you want ... he might not be real or he might be some old fart that has fun with the virgins in paradise ... if it helps you then go for it, it doesnt hurt ... as long as no one wants to impose their belief of him or lack of him upon others =P

bearbreeder wrote:use if it you want ... or dont

Definitely the take home message for me from this entire discussion

(although I have also particularly enjoyed rgold's insight and discussion on the topic)

bearbreeder, I basically raised all those issues in my posts, in some cases more than once for emphasis, so no need to burst through already opened doors. If you actually care, you have the link and can read the test yourself, draw your own conclusions, and get back to to us on how those observations affect the test's conclusions. I'm not going to do your homework for you, my own homework has been hard enough.

And while you are asking, you might apply the same newfound scepticism to the claims on, say, the Yates site, that are the basis for the perceived awesomeness of the screamer product.

i read the report a while back ... notice that i use "sinks" not sewn screamers ..

the questions i posed were not shown in that report, at least not in google translator ... perhaps you know if this was a peer reviewed study?

which is why i dont treat it as gospel till someone comes back and does a test that eliminates the human factor with a good sample size on more than just 2 particular type/brand of the dynamic ropes they used 15 years ago ...

one data point or old study does not a truth make ...

the bottom line ... use it if you want ... its not whats going to kill you if you do ... perhaps that and a prayer to the almighty should he really exists might even work ;)

Actually the facts alone produced by the manufactures, and from simple math and physic are considerable.

• How little energy a Screamer can absorb is fact.

• That the proportion of energy a Screamer can absorb in the case of a high force fall is negligible is fact.

• That Screamers lengthen the distance of a fall is fact.

It is not very surprising to me that belayers would be more steadfastly locked off after hearing a Screamer rip (even if they could see the leader!) and been give even fractions n of a second to prepare. Neither is it so surprising that fall forces in such cases would end up being higher.

To me this means

• I shouldn’t use them where there is danger of hitting the ground or a ledge.

• I shouldn’t use them of the first few pieces of a pitch. Nothing new here on the first pitch, but I am reconsidering their used on early pieces on higher pitches.

• A Screamer won’t provide significant benefit where there is rope drag because the forces will be high.

• Screamer will provide significant force reduction (in percent) where the forces are all ready quite low. Would I really have clipped a piece that suspect. I hope not

When was I supposed to use a Screamer that truly makes sense? I need to know! Otherwise the biggest benefit I can come up with will be getting the extra size and weight of the two I have been normally carrying off my rack!

Mark Heyman wrote: It is not very surprising to me that belayers would be more steadfastly locked off after hearing a Screamer rip (even if they could see the leader!) and been give even fractions n of a second to prepare. Neither is it so surprising that fall forces in such cases would end up being higher. A Screamer won’t provide significant benefit where there is rope drag because the forces will be high.

hmmmm ... are ya saying the more "static" the belay, ie friction, autolock or "hard" catches, the more "ineffective"" the screamer ...

round around the merry go round we go a screaming ..... I DUN WANNA DIE !!!!

bearbreeder wrote: hmmmm ... are ya saying the more "static" the belay, ie friction, autolock or "hard" catches, the more "ineffective"" the screamer ... round around the merry go round we go a screaming ..... I DUN WANNA DIE !!!!

Screaming? No, . . . and no one has told anyone what they should do.

Anyway, my understanding is not very effective. How effective, or innefective (either way you want to look at it ) does depend on the specifics wich you might not even fully know when it comes time to decide whether to use one or not.

for a static belay those italian and BD tests do show a significant amount of reduction for a "factor 1" fall ... i dont think thats too much in doubt

the question really becomes how do squishy climber bodies, newbie drop prone belayers using tubes, and all those other little things affect the outcome?

i think its absolutely wonderful that were jumping to how useless they are based on a 15 year old test for which we do not know the sample size (or i cant find it anyways), the randomness/double blind/human variability, whether they used a new rope every time, etc, etc, etc ...

for example if a human belayer was used id love to hear what the variability is between catches ... can you guarantee to give a catch within say +/- 5% on the force of the anchor everytime someone falls ... i sure cant ... with a large enough sample size you can get around that, but wait, we dont know the sample size ...

has it even been repeated ... thats the basic premise of any test .. the results must be reproduced and confirmed ... maybe, maybe not?

they may or may not work ... but until they are shown not to conclusively, use em if you want ... and even then keep using em if ya want ... we all know there aint no god listening on a R rated climb but i wont say anything if you sacrifice a household pet ;)

if yr worried about marketers taking away your hard earned climbing money and deceiving you, time to rail against dead birds ... if you are worried about little things that wont kill you killing you, well theres always those darn PASes ;)

bearbreeder wrote:well someone asked this earlier ... and ill repeat it ... how many people have screamers killed ...

Nobody is coming out here saying that screamers are a death waiting to happen. Nobody is saying that using them is a major issue. What people are saying though is that the perception that they are beneficial is grossly overstated, and they potentially could result in higher risks.

This is not too dissimilar to the use of homoeopathy, an analogy I raised earlier. True homoeopathy treatment has zero effect beyond the possible positive effects of placebo. However the false hope and reliance on homoeopathy treatment is a risk in itself. A risk that has resulted in deaths.

Likewise the biggest risk with screamers is the false hope given by them which may entice climbers to rely on pro that they would otherwise not do.

There have been numerous times I have placed protection while climbing consisting of small RPs and WC Zeros (3-4.5kN). I consider such protect as marginal, though I still expect(hope) that the probability of it holding is >50%. Regardless I consider my safest options are either backing off OR climbing without falling. Given the highly questional benefit of screamers, it doesn't seem sensible to rely on these for decreasing risk.

Right Patto. Bearbreeder is can't seem to keep from setting up straw men to knock down, which is not to say that his basic point, that the CAI tests may not meet National Institute for Health standards for statistical validity, isn't valid---to the extent that we don't know the details of the protocols the CAI used.

This is why everything I wrote is loaded with conditionals, caveats, and reminders about the same issues bearbreeder raises as if he were the first to ever think of them. To characterize those continually qualified statements as jumping to conclusions is absurd.

There are other absurdities. The main one is the asymmetric nature of bearbreeder's demands for statistical validity. He hasn't said a word about how invalid the manufacturer's "data" in favor of screamer effectiveness, nor does he accuse the myriads of climbers who bought into those claims as jumping to conclusions. Nor does he say anything about the validity of personal testimony in which the alternative was never tested. This gives the appearance of only being interested in disqualifying the results he doesn't like (or perhaps just attacking the messenger he doesn't like).

The fact of the matter is that there is very little, if any, testing in the climbing world that meets the standards bearbreeder suddenly finds essential for the CAI tests. If we take him at face value, we pretty much have to ignore everything we've heard about tested phenomena.

Getting back to the CAI tests, there are a few additional points worth noting. The CAI is a huge organization with resources far beyond anything in this country. They have whole buildings full of test equipment and engineers and technicians who know about statistical validity. And they have no skin in the game, their interest is in simply evaluating effectiveness. We don't know what their protocols were for the screamer experiments, but that doesn't mean that those protocols were inadequate; we just don't know what they were. The likelihood that their test results represent reality is considerably greater than most of the testing the climbing world seems happy enough to accept without question.

Add to this that there seems to be a definite pattern to the results, something you wouldn't expect if they were totally confounded with belayer performance. Stiffer systems with fall-factor 1 showed small, essentially negligible screamer benefits, with the screamer effect decreasing even within the stiffer systems when belay plates rather than Munter hitches were used, less stiff systems with fall factor 1.5 showed counterproductive screamer effects. Of course such patterns could be the result of fortuitous variation, and we have not been given measures of significance, so maybe it just happened this way because of random variations in belayer performance. Nonetheless, the patterns should give one pause, because they correspond to the expectations derived from theoretical considerations, and this includes the counterproductive results.

Unfortunately, climbers have been obliged to make decisions about their practices on the basis of evidence from tests that are rarely statistically valid in any of the professional senses. In the case of screamers, the evidence so far consists of a confluence of theory and experiment that points in a certain direction, one which climbers can either factor into their thinking or not as they choose.

If one wants to view this confluence of theory and experiment as possible evidence about screamer effectiveness, and if, based on that possible evidence, one wants to stay within the range of practices in which screamer use "can't hurt," then here are approaches one might take:

1. Put 'em on the belay anchor when rope-soloing.

2. Don't put 'em on the first or second piece if belaying with tube-style device, put 'em on the first or second piece if belaying with Grigri, Smart, Alpine Up, or other locking gadget.

3. Use them further up the pitch for short falls on crappy gear when rope friction will prevent rope running through the belay device.

4. In all cases when they are used, take a moment to reflect on Patto's, Dolgio's, and Will Gadd's warnings about the potential for enabling bad decisions.

patto wrote: Nobody is coming out here saying that screamers are a death waiting to happen. Nobody is saying that using them is a major issue. What people are saying though is that the perception that they are beneficial is grossly overstated, and they potentially could result in higher risks. This is not too dissimilar to the use of homoeopathy, an analogy I raised earlier. True homoeopathy treatment has zero effect beyond the possible positive effects of placebo. However the false hope and reliance on homoeopathy treatment is a risk in itself. A risk that has resulted in deaths. Likewise the biggest risk with screamers is the false hope given by them which may entice climbers to rely on pro that they would otherwise not do. There have been numerous times I have placed protection while climbing consisting of small RPs and WC Zeros (3-4.5kN). I consider such protect as marginal, though I still expect(hope) that the probability of it holding is >50%. Regardless I consider my safest options are either backing off OR climbing without falling. Given the highly questional benefit of screamers, it doesn't seem sensible to rely on these for decreasing risk.

i dont hear you running around telling people to stop watching honnold flicks because it may result in people going off and doing risky things ... hell i dont hear you running around telling people not to do R/X rated climbs PERIOD, because screamer or not youre rolling the dice anyways

no one is saying go off and take whippers on screamers all day long ... but FALLS CAN HAPPEN ... if you didnt youd be soloing em wouldnt you now ;)

if a person wants to risk their own life thats their choice ... im not going to go off and say whether you should use a screamer ... or if it, or any marginal gear will give you "false confidence"

thats the decision you make as a climber ... not what someone on the intrawebs can make for ya =P

rgold wrote:Right Patto. Bearbreeder is can't seem to keep from setting up straw men to knock down, which is not to say that his basic point, that the CAI tests may not meet National Institute for Health standards for statistical validity, isn't valid---to the extent that we don't know the details of the protocols the CAI used. This is why everything I wrote is loaded with conditionals, caveats, and reminders about the same issues bearbreeder raises as if he were the first to ever think of them. To characterize those continually qualified statements as jumping to conclusions is absurd. There are other absurdities. The main one is the asymmetric nature of bearbreeder's demands for statistical validity. He hasn't said a word about how invalid the manufacturer's "data" in favor of screamer effectiveness, nor does he accuse the myriads of climbers who bought into those claims as jumping to conclusions. Nor does he say anything about the validity of personal testimony in which the alternative was never tested. This gives the appearance of only being interested in disqualifying the results he doesn't like (or perhaps just attacking the messenger he doesn't like). The fact of the matter is that there is very little, if any, testing in the climbing world that meets the standards bearbreeder suddenly finds essential for the CAI tests. If we take him at face value, we pretty much have to ignore everything we've heard about tested phenomena. Getting back to the CAI tests, there are a few additional points worth noting. The CAI is a huge organization with resources far beyond anything in this country. They have whole buildings full of test equipment and engineers and technicians who know about statistical validity. And they have no skin in the game, their interest is in simply evaluating effectiveness. We don't know what their protocols were for the screamer experiments, but that doesn't mean that those protocols were inadequate; we just don't know what they were. The likelihood that their test results represent reality is considerably greater than most of the testing the climbing world seems happy enough to accept without question. Add to this that there seems to be a definite pattern to the results, something you wouldn't expect if they were totally confounded with belayer performance. Stiffer systems with fall-factor 1 showed small, essentially negligible screamer benefits, with the screamer effect decreasing even within the stiffer systems when belay plates rather than Munter hitches were used, less stiff systems with fall factor 1.5 showed counterproductive screamer effects. Of course such patterns could be the result of fortuitous variation, and we have not been given measures of significance, so maybe it just happened this way because of random variations in belayer performance. Nonetheless, the patterns should give one pause, because they correspond to the expectations derived from theoretical considerations, and this includes the counterproductive results. Unfortunately, climbers have been obliged to make decisions about their practices on the basis of evidence from tests that are rarely statistically valid in any of the professional senses. In the case of screamers, the evidence so far consists of a confluence of theory and experiment that points in a certain direction, one which climbers can either factor into their thinking or not as they choose. If one wants to view this confluence of theory and experiment as possible evidence about screamer effectiveness, and if, based on that possible evidence, one wants to stay within the range of practices in which screamer use "can't hurt," then here are approaches one might take: 1. Put 'em on the belay anchor when rope-soloing. 2. Don't put 'em on the first or second piece if belaying with tube-style device, put 'em on the first or second piece if belaying with Grigri, Smart, Alpine Up, or other locking gadget. 3. Use them further up the pitch for short falls on crappy gear when rope friction will prevent rope running through the belay device. 4. In all cases when they are used, take a moment to reflect on Patto's, Dolgio's, and Will Gadd's warnings about the potential for enabling bad decisions.

as you well know ... unless the conditions for the tests are known ... especially the sample size ... then i wouldnt go off quoting it and throwing it out there to "disprove" somthing

im havent said that screamers are proven "effective" ... note i havent quoted the yates "data" once ...

what i AM saying is that its useless to go off taking a single study done 15 years ago for which we do not know the conditions or sample size and drawing the "useless" conclusions from it ... people seem to be referencing it over and over again for some reason without knowing basic information about it ..

as to other "tests" done ... i would think one of the basic premises of any reasonable test is to eliminate or minimize the variability of the human factor ... tell me this if i fall 100 times on a tube or munter, what variability can you guarantee to give me in terms of the force on the top anchor ... +/-5% ... +/-10% ... can you guarantee that EVERY time ... gimme a number ;)

if you choose to use em go right ahead despite what "experts" (who i assumed performed their own secret tests) on the intrawebs think .... if you dont, your choice

bearbreeder wrote: i dont hear you running around telling people to stop watching honnold flicks because it may result in people going off and doing risky things ... hell i dont hear you running around telling people not to do R/X rated climbs PERIOD, because screamer or not youre rolling the dice anyways no one is saying go off and take whippers on screamers all day long ... but FALLS CAN HAPPEN ... if you didnt youd be soloing em wouldnt you now ;) if a person wants to risk their own life thats their choice ... im not going to go off and say whether you should use a screamer ... or if it, or any marginal gear will give you "false confidence" thats the decision you make as a climber ... not what someone on the intrawebs can make for ya =P

bearbreeder wrote: if you choose to use em go right ahead despite what "experts" (who i assumed performed their own secret tests) on the intrawebs think .... if you dont, your choice

I shall repeat myself.

Nobody here is denying you or other climbers the choice of using screamers. All rgold and I are doing is presenting a strong case to suggest that screamers are rarely if ever beneficial and can potentially increase risk. You seem to have taken this personally and seem to be worried that we are trying to take away your screamers.

Again. I will repeat. I am not on the "intrawebs" telling you what you can and cannot do.

Well said, patto.

patto wrote: I shall repeat myself. Nobody here is denying you or other climbers the choice of using screamers. All rgold and I are doing is presenting a strong case to suggest that screamers are rarely if ever beneficial and can potentially increase risk. You seem to have taken this personally and seem to be worried that we are trying to take away your screamers. Again. I will repeat. I am not on the "intrawebs" telling you what you can and cannot do.

And i could easily say the same about the marginal gear you use ;)

Or the redbull you drink in the morning

Or the bowlines which people tie in with which have accidents on record ...

I dont see ya fretting about those =P

Show me more than a 15 year old test for which we dont know the conditions of ...

bearbreeder wrote: And i could easily say the same about the marginal gear you use ;) Or the redbull you drink in the morning Or the bowlines which people tie in with which have accidents on record ... I dont see ya fretting about those =P Show me more than a 15 year old test for which we dont know the conditions of ...

I am failing to understand why you keep posting the same barely-coherent thoughts again, and again, and again, and again.

It is better to keep your mouth closed and let people think you are a fool than to open it and remove all doubt.

Give the ;) and =P emoticons a rest.

Jon H wrote: I am failing to understand why you keep posting the same barely-coherent thoughts again, and again, and again, and again.

It's his nature.

Jon H wrote: I am failing to understand why you keep posting the same barely-coherent thoughts again, and again, and again, and again. It is better to keep your mouth closed and let people think you are a fool than to open it and remove all doubt.

And i keep failing to understand why some people are so insistant that screamers are useless based on a 15 year old test we dont know the conditions of and as far as i know hasnt been replicated

Like i worry about what ya think on the intrawebs ;)

bearbreeder wrote: Like i worry about what ya think on the intrawebs ;)

It's not a matter of worry, but rather a pathological need to yammer on like a Yorkshire terrier long after the homeless guy has shambled on past the yard.

Calling the kettle black arent ya now stitchy ;)

I do luuuuvvv screaming princesses on TR ... Always have a screamer in that instance ;)