I'd love to hear from those with more experience. Also, for those who use comms and a shackle, are there any issues with one's mask dislodging as the comm cable pulls out after popping a shackle?
Welcome back Squirrel...
Fortunately, search line entanglement is not terribly common though we know it happens. We also know that well trained divers and well trained dive teams never make mistakes.
...and if you believe that last statement, please remember "
never say never."
It surprises me that many of the discussions on the online forums reference worst case scenarios that require a back up to the back up, and a back up to the second back up, and another back up to the third back up ... with one thing backing up another and and another thing backing up another ... you get the point.
There are divers who carry redundant pony bottles with diverter valves to the full face mask in case they forget to monitor their air supply, their tender fails to monitor their air supply and the back up diver, safety officer, team leader and others fail to monitor the diver's air supply. Then the diver carries a spare mask in case he has to doff the full face mask, and he has a spare second stage if the primary second fails and another second stage on the redundant in case the diverter valve or full face mask fails. And all of this is to cover an unlikely event.
Based on 50 years of line-of-duty death research, the facts prove that a diver is far more likely to drown because his search line/carabiner holds him underwater.
These fouled lines are NEVER planned; i.e., no one goes in the water saying
"I want to foul my line so badly that I will not be able to return to the surface." That just doesn't happen... but in fact, lines do get fouled.
And that is the reason why Dive Rescue International and many others (including PADI) suggest that public safety divers use the quick release snap shackle.
I will give you a recent scenario...
On a rainy night a dive team is called to investigate a vehicle that has run off the road and entered a rain filled retention pond. The vehicle's headlights are visible as a faint glow below the surface of the water.
The diver enters the water and walks out to waist deep water, in the direction of the submerged vehicle. As he begins to transition from his wading position to a swimming position, he feels a suction at his feet and knows that he is in proximity of a culvert pipe that is draining the high water in the retention pond to a nearby creek. He quickly pulls away from the suction and swims out to the vehicle.
At the vehicle he performs a 360 search around the perimeter of the car looking to confirm that each window is closed and any potential victim would be contained inside the vehicle. This is a recovery mode operation due to a prolonged response and warm water. The fact that the doors and windows are closed also makes it unlikely that the diver will need to search beyond the perimeter of the vehicle.
The diver reports over the comm system that he is going to return to the "shore" for the wrecker cable and straps. The tender has provided slack in the search line initially so the diver could conduct his 360 search around the vehicle.
As the diver begins his swim back towards the tender and the wrecker cable, slack is pulled out of his search/comm line. The tender is also retrieving some of the comm line but does not pull hard and only maintains what he believes is a steady tension. The night is black, the rain is coming down hard, and no one realizes that the grim reaper is moments away from claiming the life of this diver, a former teammate of mine...
Unbeknown to the diver, not all of the slack is being taken up by the tender, even though no slack is felt. Instead, the suction from the culvert pipe is pulling on the comm line. The tender does not realize that the diver has come in 100 feet and he has only retrieved 20-30 feet of comm rope.
As the diver swims towards the tender, the com line is being pulled in the proper direction, then moments later, the comm line is pulling the diver straight down, towards the suction at the end of the culvert pipe. The comm line has been pulled inside the 16 inch drain pipe. The diver struggles to pull his line free and places his feet towards the bottom so he can pull the line out of the culvert pipe. He feels the force of the suction and it pulls one of his fins off of his foot. He screams out in surprise...
This diver was my former teammate not because he died in the line of duty that night, but because I had retired off of the department months earlier. So the diver did not die as this incident played out, even though it was a close call.
The purpose of my story though is to portray a real life incident that affected a well trained team.
Had the situation been just slightly different, had the pipe been slightly larger in diameter, had the water level been slightly higher, had the discharge end of the pipe been slightly lower, a DELTA P scenario would have resulted and the only recourse for the diver would have been to QUICKLY disconnect from the comm line before being pulled into the pipe.
Unscrewing the lock on a carabiner, hoping that there would be enough slack to release the carabiner, hoping that the well trained team would be able to react fast enough, hoping that one of the cutting tools would sever the line in a split second ... none of those options would resolve the situation fast enough to prevent the certain death of the diver had the incident played out differently.
While the scenario I portrayed did not result in a fatality, public safety diver Arthur E. Schumacher was not so fortunate.
Arthur was searching around a vehicle that was located against a culvert pipe that passed under a roadway. Heavy rains and strong currents caused the vehicle to move miles downstream where is came to rest next to this culvert pipe. He searched around the vehicle and in a split second was pulled under the car by the force of the moving water finding the path of least resistance.
Arthur was a well trained diver and his team was well trained too. No one though had anticipated the scenario that played out. The tender tried to pull Arthur free and more teammates pulled frantically on Arthur's safety line too, all to no avail. Arthur had been pulled several feet into the culvert pipe and was trapped under the roadway. His regulator was torn from his mouth, his carabiner securely held him to his "safety" line and his knife remained secured in the sheath. In an instant though, Arthur Shumacher was dead and the well trained team could do nothing to save their beloved teammate.
Much later, when slack was given on the safety line, Arthur's body came to the surface at the the downstream end of the culvert pipe.
I realize there are a whole bunch of "ifs" here, but "if" Arthur had a quick release snap shackle, and "if" he had the proper reflexive action and training to release out of the system, he could likely be alive today. He may have died also... we will never know... but the fact is, he did not have an option to save himself.
There are other instances where the benefits of the quick release snap shackle are more apparent and I don't want to bore everyone with tales of death. The facts speak for themselves and evidence supports the conclusion that a quick release snap shackle offers a viable option, and we know it to be a better option, for the diver to extricate himself from life or death entanglement.
Certainly, there are exceptions to every rule and we also know that a quick release snap shackle is not suggested in overhead environments and under ice. In those situations, jettisoning from the search line will not result in a better situation in nearly all cases, so that is when a locking carabiner (possibly two) are considered.
...And to answer the question regarding the full face mask being pulled from the face, that is unlikely if the diver is using the "high use connector" (a/k/a/ HUC) and the Marsh Marine Connectors. In those instances the connectors will part (usually) before the mask is pulled from the face. With the AMP style connectors they will likely break free (with damage) and/or the mask may be pulled away. We encourage divers to manually disconnect from comm line from the mask after notifying the tender, when the situation dictates. A busted comm system or a diver having to hold his breath a few extra seconds is preferred to death because the diver is held underwater.
I hope this answers the question(s).
Regards,
Blades Robinson
