Thinker Posted June 11, 2002 Posted June 11, 2002 A question for the forum: Can a chest harness cause spinal injury? The chest harness I use for glacier travel is 1" tubular webbing tied with a water knot, crossed across my back, biner at the sternum. My rope is tied or clipped to my tie-in points on my seat harness, and runs up thru the biner on the chest harness (look at Freedom of the Hills for a picture if you're not familiar with the set-up.) A friend pointed out today that this configuration could snap a climber's spine during a sideways or backward fall. Picture the rope pulling the chest harness biner down toward the tie in point on the seat harness as it comes tight and straighens out. I suspect the spine may be damaged or break if the fall were bad enough. Does this set-up give anyone else the willys?? Quote
Dru Posted June 11, 2002 Posted June 11, 2002 Here is the solution use a cheap accessory biner on the chest harness. It wil lkeep your upper body from flopping over backwards if lightly loaded but will break if heavily loaded like you describe. Quote
glen Posted June 11, 2002 Posted June 11, 2002 Something tells me that you didn't learn that one from the mountaineers. I guess there is a real use for those little plastic biners afterall other than shameless activity identification by placement on keychains, backpacks, etc... Quote
fishstick Posted June 11, 2002 Posted June 11, 2002 As I understand it, chest harnesses can cause spine damage by snapping the neck forward. They also have a tendency to accordion the spine between the waist and chest harness. A friend tried using a carabiner attached to the shoulder strap of her pack instead, but found that a) she was catapulted forward when her partner broke a snow bridge in a big way, and b) found the system very difficult to escape because it aligned her head first to the slot. GB Quote
chris_w Posted June 11, 2002 Posted June 11, 2002 Instead of putting the rope through the biner on the chest, use a prussik on the rope and clip it into the chest biner. I also have a small piece of cord that is girth hitched to my harness and clipped into the chest harness. Keep that tight so if you fall in, the chest biner won't hit you in the chin. If the rope is clipped through the chest biner it can compress the back in some people. It depends on the physical make of the person. Chris Quote
iain Posted June 11, 2002 Posted June 11, 2002 quote: Originally posted by chris_w: use a prussik on the rope and clip it into the chest biner. Wouldn't you be worried about taking the fall force on the chest in that situation? That could be ugly. Quote
mattp Posted June 12, 2002 Posted June 12, 2002 This is pure speculation on my part, but I would think there could be situations where using a chest harness with a seat harnes could AVOID a spinal injury. The German alpine club used to recommend the use of a chest harness only, on the theory that this would elongate rather than compress your spine in a fall, and I have often wondered whether the use of a chest harness with the seat harness might sometimes place less stress on your spine -- such as in a fall where you are caught with your body oriented somewhat perpendicular to the line of the rope. For glacier travel with a large pack, and probably for general mountaineering as well (not so much for rock climbing, without a pack) a full body harness might be a good idea because it has the tie-in point higher than on a normal seat harness, and thus you can be more assured of ending up in a vertical orientation. I know some people on this board have argued that this wil cause unnecessary whipping of the spine, but when carrying a pack I believe the possible benefit probably outweighs the possible risk. Quote
fishstick Posted June 12, 2002 Posted June 12, 2002 Free hanging in a full body harness for a long period of time can cause suffocation. They tend to compress the diaphragm. GB Quote
Paul_detrick Posted June 12, 2002 Posted June 12, 2002 Don't run the rope thru the chest harness, just carry it by your side, what if you are the middle person? you could end up side down. I perfer 1 or 2 coils for walking ajustment. Quote
AJ Posted June 12, 2002 Posted June 12, 2002 Fishstick, free hanging in a sit harness for an extended period of time can also kill you. Blood will pool in the legs and within 30 minutes most people will see their upper and lower values for blood pressure equalize. I seem to recall a German study that contrasted full body harnesses to sit harnesses. I thought they found that there was no appreciable safety advantage to one over the other. Basically, it was as much personal preference as anything. Quote
Thinker Posted June 12, 2002 Author Posted June 12, 2002 Paul, I don't quite follow your logic on that one. How could the middle climber end up upside down as you described? Quote
iain Posted June 12, 2002 Posted June 12, 2002 quote: Originally posted by Thinker: Paul, I don't quite follow your logic on that one. How could the middle climber end up upside down as you described? I think he is saying if you were in a 4 person team, for example, and the front two fell in, the second to fall in would be inverted if the rope is running through a chest harness. Personally, I don't use a chest harness because I find it annoying to have the rope running out in front of me like that. I don't use a kiwi coil for the same reason. I don't get upset at those who feel them necessary, I just feel better w/o one. I have not taken a significant whipper into a crevasse w/ heavy pack though. And don't intend to. Quote
slothrop Posted June 12, 2002 Posted June 12, 2002 I always thought the chest harness was only useful after you fall in that crevasse, for keeping yourself upright while you hang and start to prusik/get raised out. Quote
gapertimmy Posted June 12, 2002 Posted June 12, 2002 some homeboys in DCSAR went to a rope rescue techniques course up in the muthaland to the north. They came back with a new chest harness config, using 1'' webbing again, but involved making little fancy loops for the shoulders, kinda hard to explain, but the reasoning behind the new system was the prevent some of the issues presented in this thread. I'll try to get a diagram and scan it. But it prevents the biner from snapping upwards and knocking out teeth, i haven't used it yet myself, and have never bailed into a crevasse either... I follow Iain's school of thinking on that one. Tim Quote
Thinker Posted June 12, 2002 Author Posted June 12, 2002 Great ideas and observations. I've always been a bit concerned about choking or being suffocated by the chest harness if knocked unconscious during a fall that leaves me hanging on the rope. I hadn't considered knocking out my teeth! While I don't plan to fall into a crevasse, sh*t happens when you're on the road less travelled. Quote
haireball Posted June 13, 2002 Posted June 13, 2002 Thinker - if you're using a single carabiner to join the two lobes of a chest harness, and simply passing the rope through that biner to your seat harness, that carabiner would likely fail under the three-way load generated by a hard fall. Many experienced chest-harness users prefer to make this connection with a tri-link (designed to sustain a three-way load), or use two carabiners-one from each lobe of the chest-harness to the rope. The risk of folding your spine can be eliminated by clove-hitching the chest-harness linkage. I've found this rig comfortable for lengthy hangs in rescue applications. I've also caught crevasse falls on the kiwi coil, and on my "backpack-rigged-as-a-chest-harness", and I've taken one significant crevasse fall wearing the "backpack-rigged-as-chest-harness". It was cush having my pack support me while I hung free in the crevasse, rather than vice-versa! Perhaps more critical for safety on glaciers is keeping sufficient rope, and NO SLACK between rope team members. By thus minimizing the fall-factor, the forces transmitted to the rope-partner(s) will be slight - I've caught a number of crevasse falls without even being pulled off my feet... and in the one fall I took, the force transmitted to my partner (who was out of sight over a bulge) was so slight that she thought I had just begun walking faster, so she kept walking, and lowered me forty feet into the crevasse before she figured out what had happened! Paul Detrick - I eliminate the risk of inversion for middle-partners by hitching both of their strands to the chest-harness linkage... [ 06-12-2002, 07:00 PM: Message edited by: haireball ] Quote
Paul_detrick Posted June 13, 2002 Posted June 13, 2002 Thanks iain for answering that for me it was right on, I think this is a good topic, and good replys, theres more than one way to do just about everything, just be safe. Quote
Thinker Posted June 13, 2002 Author Posted June 13, 2002 Haireball- great ideas, I can tell you think about this, too. Let me reiterate your clove hitch solution to make sure I understand. "One solution to the problem of the 'folding spine' is to clove hitch the rope to the chest harness biner rather than letting it 'run thru'". Correct interpretation? Re crossloading: anytime I've tugged on the chest harness biner, both bights of webbing have moved easily to the end of the biner, avoiding crossloading potential. Does this indicate a chest harness that's too large (a potential tooth knocker?) Another troublesome fall scenario I see is a leader sliding on an icy slope head first, unable to self arrest. (Of course, any climber worth his grit would have running protection placed in that situation.) As the rope comes tight, the chest harness biner is pulled down to the tie in point on the seat harness, potentially crumpling the spine untill the body is turned around. Having a properly spaced clove hitch on the chest harness biner seems like it may reduce (but not eliminate) the risk to the spine. I'll toy with the 'pack as a chest harness' idea a bit, it sounds more reasonable. Thanks for your insight. Quote
Jarred_Jackman Posted June 13, 2002 Posted June 13, 2002 I can't bypass this one. So what if you end up upside down, hasn't anyone ever fallen and ended up upside down? I can't be the only one. Just flip yourself right side up and forget the chest harness at home, it's just something else to clutter up the whole gettup anyhow, makes taking off clothes more cumbersome, layering and what not. I just stopped using it after I fell upside down and realized it isn't that hard to grab the rope and right yourself. I suppose if you're unconscious that's another story but there are bigger problems if you're unconscious after a fall. [ 06-12-2002, 09:45 PM: Message edited by: Jarred Jackman ] Quote
pindude Posted June 13, 2002 Posted June 13, 2002 Okay, this is second-hand, but reliable, and worth relating for this discussion. Two friends of mine were on Liberty Bell this past weekend, and crossed paths with an AAI (the original Am Alpine Inst, not Alpine Ascents Intl) and AMGA-certified guide who was leading another party. According to the guide--my buds didn't ask his name--the AMGA will be releasing a study (whose?) detailing why chest harnesses are dangerous and are no longer to be used, including for glacier travel. The guide says AAI no longer uses chest harnesses. Any AAI, AMGA-certified, or other guides out there who are in the loop and know about this study, or can relate details? --pindude Quote
pindude Posted June 13, 2002 Posted June 13, 2002 quote: Originally posted by crazyjz: CFR 1926 requires construction dudes ( and dudettes ) to use full body harnesses, although these are typically clipped in the back. There is no prohibition against a front tie in if the harness is so designed. These laws were designed around extensive testing by the American National Standards Institute. All in all I don't know what to think about all this. We sandblasted all the f&%#$n graffiti off the main climbing walls at Minnehaha in Spokane over the past month or so (enjoy urban climbing on fresh rock next time you're Spokane-way)...one of our main sandblast dudes originally used his construction full body harness to hang from, and he was as uncomfortable as I've seen anyone hang in a harness--he was complaining pretty loudly too. While it may be construction-approved, that doesn't make it comfortable (or maybe any safer?). I'll take a wide-waist-belted good seat harness any day, like a Misty Mtn Caddy, Petzl Gourou, or better yet, a Yates Big Wall or other harness meant to hang out in. --pindude Quote
David_Parker Posted June 13, 2002 Posted June 13, 2002 I would be inclined to wear the chest harness if the possibility of falling in a crevasse was "higher than average"; whatever that is. Still, I wouldn't clip it in until after I was hanging in a crevasse, hopefully not unconscious. There's risks no matter which way you do it. Quote
crazyjizzy Posted June 13, 2002 Posted June 13, 2002 CFR 1926 requires construction dudes ( and dudettes ) to use full body harnesses, although these are typically clipped in the back. There is no prohibition against a front tie in if the harness is so designed. These laws were designed around extensive testing by the American National Standards Institute. All in all I don't know what to think about all this. [ 06-12-2002, 12:38 PM: Message edited by: crazyjz ] Quote
Dru Posted June 13, 2002 Posted June 13, 2002 quote: Originally posted by AJ: Fishstick, free hanging in a sit harness for an extended period of time can also kill you. Blood will pool in the legs and within 30 minutes most people will see their upper and lower values for blood pressure equalize. . So can riding in an airline......for the same reason.... This from the guy who forgot the belay seats for Space Shot. EXTREME DEATH RISK!!!! Quote
Thinker Posted June 13, 2002 Author Posted June 13, 2002 Found this last night after several combinations of search terms. http://www.alpineclubofcanada.ca/services/safety/harness.pdf The translation from Italian is not particularly good, but the conclusions are unmistakeable... "The Central School has decided that during all mountaineering courses and free climbing it is recommended that the combination harness be used. The use of the sit harness is recommended only when climbing without a backpack. In regards to movement on a glacier, the attachment of the rope to the harness has to be in a fashion as to only effect a pull on the sit harness." It appears that if a chest harness is rigged properly, it can provide additional safety, esp when wearing a pack. But, if rigged improperly, can cause more damage to the climber than not having one. I look forward to seeing what AMGA comes up with. [ 06-13-2002, 10:52 AM: Message edited by: Thinker ] Quote
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