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Snap shackles or Carabiners

Discussion in 'Public Safety Divers/Search and Rescue' started by CCTX50, Mar 30, 2010.

  1. bridgediver

    bridgediver Instructor, Scuba

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    Where I'm coming from here is that in the past locking carabiners were still prefered for ice diving while snap shackles were recommended for the non-overhead type of diving (was also trying to get Blades to verify this is still the case first). The reasoning is that in an overhead you don't want to loose your line (I think we all can agree on that). My thinking is that if the locking carabiner is safe for ice diving why is it not safe for all other types of diving?
    If ice diving is putting our divers more at risk than the other forms then perhaps we need to re-think procedures.

    I agree that many don't have ice to worry about (lucky you!) but an overhead either soft or hard is still a hazard. Can you 100% of the time say that there will never be anything above you when you surface? (boats, docks, sub-surface debris, more entanglements floating mid water, fences, wire etc). Don't forget we are in zero vis to balck water (most of us) so you may not be aware of the overhead. Not everything is seen on the surface and/or before the dive.
    This is why I'd prefer to keep the diver on a tether from the moment he steps in the water until he's out

    Mud and Thal - Correct me if I'm wrong but your umbilicals are also used to haul you out of the water are they not? Ours aren't meant for life safety in the manner of supporting the weight of a person (even though the comrope can do that in a pinch - 5000lbs I believe it is?). No fall factors and 9:1 ratios are needed for our tethers
    We also don't use it near as much as you guys so abrasion resistance I wouldn't think is that huge for us(?).

    Our team also carries multiple EMS shears so if things really do go bad it takes a couple of seconds to pull them out and cut the comrope (it cuts easy with shears). BUT, it would be the very last thing we would ever try. It would have to be a very deliberate act to do if the diver thought there was no other choice - certianly not as reflexive as a quick release shackle and I think this is a good thing.
    So I guess I'd never say never either:wink:

    BTW - feel free to call me out anytime. I'm always trying to make things better for my guys but I don't know everything
     
  2. Chad P.

    Chad P. Public Safety Diver

    # of Dives: 100 - 199
    Location: Milan, Georgia
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    I don't think anything about a psd dive is ever 100% due to the wide variety of situations in which we may find ourselves. By remaining flexible, we can maximize safety based on what we are facing. A lot of our dives are in black water rivers approx. 12-15 feet deep, with a lot of debris (trees, root balls, etc.). I have had my safety line become entangled a good distance from me. I was able to back track and free the entanglement without having to come off the line. But was that not the case, having the option to readily bail would have been beneficial.

    The point I am making is why should we limit ourselves by saying we should always use carabiners or always use snap shackles. Why not have as many options as reasonably possible available to us, train on the different ways, and then let the decision as to which to use be determined by the task we are trying to accomplish.

    I also prefer to always have the diver on a tether from the moment they enter the water. But were the conditions to change to a situation where the diver is safer to come off the rope, I want him/her to have that option.
     
  3. BladesRobinson

    BladesRobinson ScubaBoard Supporter ScubaBoard Supporter

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    I believe that some dives (overhead environments / ice diving) are more risky than others and that is the reason why most training agencies suggest ADDITIONAL training for these situations. I also believe that in addition to specialized training, specialized techniques and specialized tools of the trade are required.

    Trying to have a "one shoe fits all" approach to diving, particularly in public safety diving, is dangerous, cumbersome and may not be in the best interests of taxpaying citizens we serve. If flexibility is not allowed, then the extreme is that ice shelters are carried to every dive site, even when it's not cold outside, we hang high lines on every operation, even when there isn't current, and we carry metal detectors on every dive since that is part of a "system" that is used when searching for evidence.

    I believe (and I suspect most would agree) there needs to be some common sense and flexibility so teams can operate efficiently, effectively, AND SAFELY!

    In the same way some will adjust thermal protection and weights based on seasons and water temperature, I do not see a problem with divers using a common sense approach to when quick release snap shackles are worn and when they might choose to use a locking carabiner only.

    If we can trust divers to use shears to cut their com rope when things go bad, can we not trust them to use quick release snap shackles???

    Bridgediver asked in his earlier post "Where was the back-up diver? redundant air source?"

    In two scenarios I mentioned earlier, one involving a former teammate and another involving Arthur Schumacher, the back up divers were on shore, standing by. In both scenarios neither a safety diver nor a redundant air source will save a diver in a Delta P scenario. When a diver's safety line is being pulled into a turning propeller, the redundant air supply and vigilant teammate offers little help.

    ANOTHER REAL LIFE INCIDENT...
    A commercial diving crew performing regular field maintenance from a lift boat in 25 ft of water in the Gulf of Mexico experienced a potentially catastrophic near miss. Approximately 70 ft of the divers umbilical was pulled into the lift boat propeller before it was completely severed less than 20 ft from the diver.


    It is apparent that some will choose locking carabiners on all dives and rely on shears and redundant air supplies to resolve problems.

    I am of the opinion that we should give divers good training and good equipment if we want divers to make good decisions and have operations with favorable outcomes.

    GOOD TRAINING is paramount and I trust divers with good training to make good decisions.

    I suspect too that there are some divers who should always be locked in with a carabiner and for those divers, a padlock may actually be more effective. Keeping them away from the water may likely be the best option!

    In summary, I do not believe that quick release snap shackles offer a benefit to divers working under ice.

    Additionally, based on my experience and study, and based on the opinions of people whose opinions I value, I strongly believe that a quick release snap shackle offers an enhancement to the "safety" of public safety dive operations in most cases. Even PADI agrees!

    Respectfully,

    Blades Robinson
     
  4. muddiver

    muddiver Divemaster

    # of Dives: 500 - 999
    Location: West Coast USA
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    bridgediver - Yes, the rope portion of a commercial divers umbilicle has to be strong enough to lift the diver, if necessary. That would not be the optimum method of removing a diver from the water when most job site usually have a Stokes basket and/or the diver has an unlimited air supply. You can always wait for help.

    Yes abrasion resistance is a major reason for the commercial/Navy type umbilicle design.

    Chad P. - In major metro areas that have over lapping juridictions and mutual aid agreements, would it not be wise to standardize equipment and techniques for such a specialized public safety function? As a former Forest Service firefighter I can attest to a number of times a water tender has pulled up to refill our engine and the crews stand between the trucks scratching their heads over how to connect a 1 1/2" NFPA thread coupling to an 1 1/2" NPS thread pump outlet. Now most Forest Service engines look like the plumbing section at Home Depot to try and be effective during mutual aid.
     
  5. muddiver

    muddiver Divemaster

    # of Dives: 500 - 999
    Location: West Coast USA
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    One of the best ways to rig the pull on a Spinnaker shackle is to find someone that is good a macrame or a good rigger and have them weave a crown sennit with finished end as a pull lanyard that will not snag. There are no loops in the knot and it makes a nice handle.
     
  6. Thalassamania

    Thalassamania Diving Polymath ScubaBoard Supporter

    # of Dives: 5,000 - ∞
    Location: On a large pile of smokin' A'a, the most isolated
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    That's exactly what we do, looks good ("salty" too!). But then we mouse our unbillicals with net twine, no duct tape.
     
  7. Chad P.

    Chad P. Public Safety Diver

    # of Dives: 100 - 199
    Location: Milan, Georgia
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    Yes I agree it is wise to have standardized equipment and techniques. Where I disagree is having a standard dictate the use of equipment or technique without considering the task at hand. I'll use search patterns as an example. We train using several different search patterns (Arc, Jackstay, Grid, Expanding square, etc.). These are all standardized search techniques. But when we arrive on the scene, it is up to the dive team to determine which technique to apply based on the conditions. An arc pattern in a pond with a submerged tree stand would not be effective. Likewise using the ice dive example, when in an overhead environment a locking carabiner may be the best set-up, but in a pond with little chance of overhead obstruction, the snap shackle may be the best option.

    Being located in a rural area, the fire and dive teams both are primarily volunteer. Which inherently means that mutual aid is often needed to produce enough divers to safely conduct the operation. On a recovery last week, the operation was conducted with members from four different teams located in four different counties working as one unit. Having standardized techniques allowed this to be possible. But having standards does not mean that there is only one way.
     
  8. Akimbo

    Akimbo Lift to Freedom Volunteer Staff Member ScubaBoard Supporter

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    Like Muddiver, I have also have never seen anything but snap shackles on modern umbilicals; military or commercial — except a few old Jack Brown/Desco mask rigs that depended on a bowline tied around the divers waist and on heavy gear. Add the North Sea to his list.

    I am not arguing for or against them in rescue applications since it is not my circuit, but I have never heard of a snap shackle accidentally coming loose in commercial or military diving operations.

    BTW, you can buy various length macramé lanyards from West Marine for snap shackles.
     
  9. BladesRobinson

    BladesRobinson ScubaBoard Supporter ScubaBoard Supporter

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    I think it is pretty safe to say if there was a probability, the military would have banned them years ago and the ADC would have released a safety notice to their members.

    I hope this allays any fears about the quick release snap shackles coming open by accident. I will stick to the rule of "never say never" but I believe that the odds of winning the lottery and being struck dead by lightning on the same day are in par with a snap shackle coming open by accident.

    To the commercial guys who have checked in on this forum to see what's going, thanks for your comments!

    Respectfully,

    Blades Robinson
     
  10. Thalassamania

    Thalassamania Diving Polymath ScubaBoard Supporter

    # of Dives: 5,000 - ∞
    Location: On a large pile of smokin' A'a, the most isolated
    22,171
    2,770
    113
    I believe that Akimbo means a spinnaker shackle when he says a snap shackle (ah ... the joys of nomenclature!).
     

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