"Swim-through" okay for open water divers?

[OMyMyOHellYes]

I did my first real open water diving at AKR off of Roatan and I've gone back there.

AKR seems to delight in taking their boat groups through swim-throughs. By "swim-through" I mean tubular passages through the reef open on either end. Usually several meters, sometimes tens of meters long. Some more; some less. Those formations that I've been through there usually have room for a diver to go through OK but at some point along the way usually not clear for two divers comfortably.

If it's a narrow, closed top formation, more than just a few yards long, I tend to just solo it up to the top/side of the reef and wait it out looking for the bubbles to pop out the other end. It is not so much the concept of the swim-throughs, but the lack of coordination and instruction for the group and a broad capability continuum amongst the divers. Some of the folks on the boats are really good, some can barely manage putting their "flippers" on pointing the right direction. A briefing that goes "We'll drop in to 75' on the wall then make our way forward to a swim through and circle back to the mooring line. We'll be down 45 minutes and might see a green moray. Everybody ready? Pool's open!" doesn't get it done. How about including "Does anyone have problems with a swim through?" or "once we get to the swim-through, entrance and exit are at about 40 feet depth, it's about 50 feet long with a minimum clearance of about 3 feet in one place after it makes a slow turn to the left. Go in, maintain your buoyancy and don't bump, touch, or stir up anything, do not stop - keep up with me and the diver in front of you. Did I mention do not stop? There will be people behind you. Did I mention nailing your buoyancy? You with the camera, this is not your opportunity to stop and hover for a few minutes to try and get the perfect shot of that wooly snooted cave worm hiding in the crack. Keep going because you've got people behind you that need to keep moving. Do not execute a Warhammer maneuver with people behind you in the tube..."

On those early dives getting trapped behind someone who decided to stop with others pushing up behind me caused a great deal of anxiety. We'll leave it at anxiety....

I'll go with a few other known, capable divers when we're all on the same page, with accessible redundant air/equipment and we understand the plan and what's going on... Cattle car? I'll usually go look for bubbles at the top of the formation unless I'm the first one in line behind the DM...

 

[boulderjohn]

Trying to make this a bright-line "yes it's fine", or "no it's not", is impossible. For simple swim throughs (coral arches, open and unobstructed wheelhouses on artificial reefs, etc) I think the only skill one needs is the ability to control buoyancy. If you're not bouncing off the sand or crashing into the overhead, you should be fine. If it involves anything more complex, like obstructions or the possibility of limited visibility, that's a different story.

The term "swim through" is vague, undefined, and covers a lot of territory. Some that would be fine under some conditions are probably off-limits under others - a wheelhouse on a boat that's upright in 50 feet of water is different than one on it's side in 100 feet. Asking a broad question like "are they okay for open water divers" makes for interesting discussion to a point, but without consensus on what a swim-through is (and more importantly, isn't) there's never going to be an answer.

And that is my point. The "just say no" policy is bad because once you realize some overheads are OK for you at your training level, you are left with no guidance as to which ones are not OK for you. It is better to teach divers of the dangers inherent in various kinds of overheads and teach them that they have to make good judgments about the ones they are thinking of taking on.

 

[jadairiii]

Is there a certification for diving a simple (say 10') swim-through? If a vacation diver wants to take 15 seconds to go from one side of the wheelhouse to the other, is a cave diving certification and cave diving gear necessary?

Did your vacation diver just get his/her resort course certification from the Resort's on-staff instructor (who's not really an instructor)? Or did your vacation diver finish one of your advanced open water classes? Is that vacation diver beginning the swim through at the start of his/her dive or at the end with 200psi in the tank?

At a minimum, advanced open water, and hopefully the instructor for that class is you and not some hack that just took their money and gave them a card. I rescued a diver on a wreck that if she had done the 10' swim-through at the end of her dive she would be dead. Virtually every decision she and her buddy made on that dive was wrong.

What class teaches a diver serious gas management?

 

[Belzelbub]

As with most things, it depends.

Dimensions of the swim through are important. If it's wide enough so there's no issue of getting stuck and short enough that it's unlikely to trigger any fear, then it's probably OK. It shouldn't be a requirement.

My daughters did some of their checkout dives at Devil's Den. It has a short swim through and I think it fits to be OK. My older daughter did it during the checkout. I believe my youngest daughter opted not to do it. Regardless of the size, I wouldn't make it a requirement, but have no issue with some minor swim throughs.

 

[brsnow]

Divers are responsible for themselves, no certification gives an accurate portrayal of a diver’s ability.

 

[jborg]

What would be rating if this swim through, our local cathedral sea cave system, a video by the local dive charter operator?

I would have noped out at the one minute mark. That’s end of “swim through” territory for me…

 

[Eric802]

I did my first real open water diving at AKR off of Roatan and I've gone back there.

AKR seems to delight in taking their loosely led boat groups through swim-throughs. By "swim-through" I mean tubular passages through the reef open on either end. Usually several meters, sometimes tens of meters long. Some more; some less. Those formations that I've been through there usually have room for a diver to go through OK but at some point along the way usually not clear for two divers comfortably.

If it's a narrow, closed top formation, more than just a few yards long, I tend to just solo it up to the top/side of the reef and wait it out looking for the bubbles to pop out the other end. It is not so much the concept of the swim-throughs, but the lack of coordination and instruction for the group and a broad capability continuum amongst the divers. Some of the folks on the boats are really good, some can barely manage putting their "flippers" on pointing the right direction. A briefing that goes "We'll drop in to 75' on the wall then make our way forward to a swim through and circle back to the mooring line. We'll be down 45 minutes and might see a green moray. Everybody ready? Pool's open!" doesn't get it done. How about including "Does anyone have problems with a swim through?" or "once we get to the swim-through, entrance and exit are at about 40 feet depth, it's about 50 feet long with a minimum clearance of about 3 feet in one place after it makes a slow turn to the left. Go in, maintain your buoyancy and don't bump, touch, or stir up anything, do not stop - keep up with me and the diver in front of you. Did I mention do not stop? There will be people behind you. Did I mention nailing your buoyancy? You with the camera, this is not your opportunity to stop and hover for a few minutes to try and get the perfect shot of that wooly snooted cave worm hiding in the crack. Keep going because you've got people behind you that need to keep moving. Do not execute a Warhammer maneuver with people behind you in the tube..."

On those early dives getting trapped behind someone who decided to stop with others pushing up behind me caused a great deal of anxiety. We'll leave it at anxiety....

I'll go with a few other known, capable divers when we're all on the same page, with accessible redundant air/equipment and we understand the plan and what's going on... Cattle car? I'll usually go look for bubbles at the top of the formation unless I'm the first one in line behind the DM...

I had this exact experience in Grand Cayman in the 90's, only I wasn't smart enough to swim over. "We're going to drop down to the sandy bottom and make our way to the wall. There's a coral swim-through on way we can go through. When we hit the wall, don't go below 100ft...". We hit that swim through and I'm guessing it was 6-7 feet across and maybe about as high, and (total guess here) 10 feet long? First person through probably loved it, but after a few more divers bounce through on their knees the visibility was about zero and when I got partway in I couldn't see a thing. I realize now that I wasn't comfortable or skilled enough at that point to be doing that, under those conditions. Had a little "oh sh!t" moment, as I recall, but blundered my way out and enjoyed the rest of the dive.

 

[Saboteur]

I did my first real open water diving at AKR off of Roatan and I've gone back there.

AKR seems to delight in taking their loosely led boat groups through swim-throughs. By "swim-through" I mean tubular passages through the reef open on either end. Usually several meters, sometimes tens of meters long. Some more; some less. Those formations that I've been through there usually have room for a diver to go through OK but at some point along the way usually not clear for two divers comfortably.

If it's a narrow, closed top formation, more than just a few yards long, I tend to just solo it up to the top/side of the reef and wait it out looking for the bubbles to pop out the other end. It is not so much the concept of the swim-throughs, but the lack of coordination and instruction for the group and a broad capability continuum amongst the divers. Some of the folks on the boats are really good, some can barely manage putting their "flippers" on pointing the right direction. A briefing that goes "We'll drop in to 75' on the wall then make our way forward to a swim through and circle back to the mooring line. We'll be down 45 minutes and might see a green moray. Everybody ready? Pool's open!" doesn't get it done. How about including "Does anyone have problems with a swim through?" or "once we get to the swim-through, entrance and exit are at about 40 feet depth, it's about 50 feet long with a minimum clearance of about 3 feet in one place after it makes a slow turn to the left. Go in, maintain your buoyancy and don't bump, touch, or stir up anything, do not stop - keep up with me and the diver in front of you. Did I mention do not stop? There will be people behind you. Did I mention nailing your buoyancy? You with the camera, this is not your opportunity to stop and hover for a few minutes to try and get the perfect shot of that wooly snooted cave worm hiding in the crack. Keep going because you've got people behind you that need to keep moving. Do not execute a Warhammer maneuver with people behind you in the tube..."

On those early dives getting trapped behind someone who decided to stop with others pushing up behind me caused a great deal of anxiety. We'll leave it at anxiety....

I'll go with a few other known, capable divers when we're all on the same page, with accessible redundant air/equipment and we understand the plan and what's going on... Cattle car? I'll usually go look for bubbles at the top of the formation unless I'm the first one in line behind the DM...

That would be a great briefing.

 

[OMyMyOHellYes]

Just to stir a little bit ... Granted, this is way out there, but what happens in/to the dive-through if there's an earthquake?

Thought had never really occurred to me, but it happened on my last trip to RTB. I think it we were on Overheat Reef site. It was really deep, about 60 km NW of Sandy Bay, big scary noise and nobody knew what it was until we were topside.

But the question occurs to me what if the seabed started moving locally...

OMMOHY

 

[boulderjohn]

Did your vacation diver just get his/her resort course certification from the Resort's on-staff instructor (who's not really an instructor)? Or did your vacation diver finish one of your advanced open water classes? Is that vacation diver beginning the swim through at the start of his/her dive or at the end with 200psi in the tank?

At a minimum, advanced open water, and hopefully the instructor for that class is you and not some hack that just took their money and gave them a card. I rescued a diver on a wreck that if she had done the 10' swim-through at the end of her dive she would be dead. Virtually every decision she and her buddy made on that dive was wrong.

What class teaches a diver serious gas management?

Since you decided not to answer my question, I will ask it again. What class specifically teaches students to enter overhead environments such as short swim-throughs like the wheelhouse of a wreck? I ask because I am sure i have seen hundreds of posts on ScubaBoard telling divers not to go into even the simplest overhead environment without certification. I am just asking for the name of that certification.