"Swim-through" okay for open water divers?

[rx7diver]

SB Faithful,

A currently-running SB thread has diverted (temporarily?) into posts about swim-throughs. I am wondering if you feel it is okay for an open water-level (recreational) scuba diver to travel through a "swim-through." Ever? Only under certain circumstances? Other considerations?

My personal opinion? Especially regarding new, inexperienced, or out-of-practice open water divers, I personally think that swim-throughs are NOT appropriate, and should be avoided/declined/eschewed, for open water divers.

We all learned that being able to make a direct, immediate ascent from depth to the surface at any point in the dive is an imperative for safe open water diving. So, there's that.

A bit deeper: Can a diver share air while inside the swim-through if necessary? If the diver is delayed (say, by snagged kit, or delayed diver traffic in front of him/her, etc.), can he/she survive the delay? Can a diver assist or rescue a dive buddy while inside a swim-through? More.

My college junior daughter was certified last spring. As she was preparing to leave for her open water check-out, and afterward for her dive trip to Roatan, I cautioned her: ABSOLUTELY NO SWIM-THROUGHS! Of course, I had the gear (e.g., long regulator hoses, redundant stuff, etc.) and knowledge (e.g., of gas planning and protocols for diving in overhead environments) to explain why.

I am looking forward to your opinions.

rx7diver

 

[Doc]

The deciding factor for me if wearing the DM hat?

1) Perfected buoyancy control

2) Low level of excitability

Divers often present agitated behaviors when doing a simple swim thru, this results usually in hyper ventilating that makes them positively buoyant.

Head whacking might ensue- more likely iron contacting flora/fauna. Not good either.

I might see the rest of your immediate concerns to be overthinking it a bit, but certainly worthy of discussion. I’d say eliminate my two factors and things get simpler from there.

Esoteric definitions of swim thru, over-head environments and parsing words will now also ensue…

 

[BoltSnap]

Especially regarding new, inexperienced, or out-of-practice open water divers, I personally think that swim-throughs are NOT appropriate, and should be avoided/declined/eschewed, for open water divers.

Agree, I believe the same.

 

[Lorenzoid]

You haven't defined "swim-through." Is the proverbial swim under the anchor chain a swim-through?

In my opinion, we might as well call all things swum under, through, etc., a "swim-through." There's a huge spectrum between the swim under the anchor line and the Devil's Throat tube in Cozumel.

As for what's appropriate, I consider it an OW swim-through if I can see daylight from the other side, it's not much longer than a couple of diver lengths, and it's wide enough that if something were to happen in there another person could fit beside me to assist. Even then, such a swim-through may not be appropriate for all OW divers at all times, depending on experience and personal comfort zone.

 

[Doctorfish]

I tend to agree with OP. On many Caribbean diving trips I have seen recreational divers get scraped, bang their heads and occasionally panic in swim throughs. Having a train of divers go through, many of whom kick up sand, leaves those caught in the middle sometimes feeling trapped.

There are swim throughs and there are swim throughs, and if short and not crowded, do not pose a risk. On the other hand, a long narrow swim through with a group has the potential to be a disaster.

Generally, if on a group dive, if the group goes through a swim through, I always go around. If I'm out with one or two dive buddies, know the geography, and I can see blue on looking in, I might go through.

One of the worst experiences I ever had when I was a new diver was at Grand Cayman, Trinity Caves. I was in the middle of a group of divers who kicked up lots of sand from the bottom causing a total loss of visibility. I was stuck in the middle with no way forward or back and no way to communicate with the divers in front of me who stopped moving forward. By the time I was out, I was down to 600 PSI and still had my ascent and safety stop to go. I was sucking an empty tank when I got to the ladder of the dive boat. It could have been much worse.

 

[rhwestfall]

I was newly minted and showed up with only my cert dives to an island in the Bahamas. One dive had a plan of dropping through a swim through and popping out of the wall. I said I wasn't keen about it to my assigned buddy. We splash and the next thing I know my buddy drops in and leaves me. I swam around on the shallow top of the reef a bit, and returned to the mooring. Climbed aboard, and got grilled as to where my buddy was. I said "he left me". The next dive I was partnered with a DM who was "interviewing" for a position. Learned a great bit the rest of the week.

The other guy probably was relieved to rid himself of the newby...

Part of why I try to help others....

 

[-JD-]

Well, our 4th checkout dive (with my then 13year old son) was a tour through the Kittiwake - lengthwise. So my expectations may have been set a bit differently as a baseline. Looking back, I was not prepared to be fully self reliant in training, experience, or equipment for that kind of environment. However it was a guided dive under the supervision of an instructor, not at all crowded, and just the two of us with the instructor. Was it "right" - dunno.

Moving forward, I did a cenote tour last June in an environment that (while there was extensive debate about the technical/legal definition) was to my practical judgement a full cave environment. I dove with full redundancy (independent doubles, 3 lights, spare mask) with my own expectation that if SHTF, I was prepared to deal with contingencies and follow the line out on my own if required.

As in life there are lots of steps up in risk in diving. Depth, buddies (for good and bad), complexity/distraction (ex. camera), all also factor in to combined risk level.

@rx7diver you make a pretty case for the factors. Reasonableness is modified, by training, experience, equipment, and personal risk tolerance. As a parent you, for good prudent reason, attempted to impose your experienced judgement and risk tolerance on your daughter. As a parent and former teenager, I know that what happened may or may not have perfectly matched up to that.

 

[Vicko]

What are swim troughs?
How many divers died in swim troughs?

There's a cave on Šolta island in which so far 7 divers died, 3 of them on the same dive. It was considered a swim trough by pretty much every dive center in the country but anyone with eyes can tell it's full cave territory.
On the other hand one of my favorite dives here on the island are caverns with rooms big enough that you can always see the entrance but you can't shine a light from one side to the other. Because of the sheer size I can see someone considering them caves but for me they are swim troughs. I'm perfectly happy to go in with a group of open water divers and don't see them as anything more dangerous than fully open water.

 

[Eric802]

My OW certification dives were in a quarry in Wisconsin, with most of the skills demonstrated while kneeling on top of a sunken school bus in about 25 feet of water. On the second or third dive, after we'd finished the skills for that dive, the instructor had us swimming through the bus. So that particular PADI instructor had us doing "swim throughs" before we were actually certified.

 

[Doctorfish]

Doc is right but unfortunately, many recreational divers do not have perfected buoyancy skills and/or low level of excitability.

A good DM would be able to assess these thing most of the time but not always. Stress an inexperienced diver and they hyperventilate. A long swim through is a great way to stress an inexperienced diver.


I'm glad this topic came up for discussion.