Surface support station, whose responsibility?

[KJackson60]

I would be interested in hearing "where" ...

"PADI recommends that one be used on any recreational deep dive, eg deeper than 60 feet"

Top of page 73 and bottom of page 74 of the Adventures in Diving manual. While not specifically saying you have to have a support station it is strongly suggested as a "requirement" for safe deep diving.

 

[down4fun]

Like others have said you should always carry enough gas to complete your dive via good gas planning.

That being said, I have seen a reg hung overboard on the MV Spree, which is a live aboard for emergency use only. The only time I have seen a "support station" deployed from a day boat was in Grand Cayman during Innespace where we were completing 300ft dives daily and there was a deco station in the water. As NWGD explained this was pure O2 hung at 20 feet.
For everyday diving in Florida, including technical diving, it is thoroughly expected that you will carry all the gas you need to finish your dive including any and all stops necessary. Sea conditions such a wave height and current can make a support station a little tricky if not dangerous. And if a full deco station is deployed, it makes the boat non-movable until the station is pulled up. So any diver needing assistance away from the boat is on there own.

 

[MXGratefulDiver]

I would be interested in hearing "where" ...

"PADI recommends that one be used on any recreational deep dive, eg deeper than 60 feet"

Top of page 73 and bottom of page 74 of the Adventures in Diving manual. While not specifically saying you have to have a support station it is strongly suggested as a "requirement" for safe deep diving.

Probably because PADI can't be bothered training divers how to manage their gas supply.

A recommendation does not equate to a requirement.

The reason you don't see it very often is because in most recreational settings it's a dumb idea ...

... Bob (Grateful Diver)

 

[Jonny boy]

Sorry for the confusion. I was referring to the responders of this thread, most of whom seem to be more involved with Technical style dives or who indicated they carried a pony of some sort. This actually does not apply to everyone so I will withdraw the statement.

[-] If PADI taught people how to calculate their gas requirements rather than come back to the boat with more than 500PSI, (eg see Rock Bottom calculations in NWGrateful Diver's sig line,) it would be harder to "just run out of gas".[/-]

I agree that gas planning is not covered to the degree it should be. How ever if someone is out of gas and is doing a CESA I do not think they are stopping at a support station on the way up. The intent is to supply extra gas for someone who does not have enough air to complete an additional 15-20 minute hang because of staying past their NDL time. This may be to not paying attention (usually) or because of some other factor. It is not my intention to condemn or support this practice and in fact I agree with much that has been said in this tread.

If you have got an 'accidental' 20mins deco to do on a 70-80ft dive then, in my humble opinion, you need to seriously address you diving practices.....
Although i would note that on the deeper recreational dives out here it is fairly standard to drop a bottle on a 5 metre length of rope 'just in case.' This is, i believe, aimed at people who chuff through their gas rather than people that rack up a significant amount of deco 'by accident.'

 

[MXGratefulDiver]

Although i would note that on the deeper recreational dives out here it is fairly standard to drop a bottle on a 5 metre length of rope 'just in case.' This is, i believe, aimed at people who chuff through their gas rather than people that rack up a significant amount of deco 'by accident.'

That is the rationale I've seen applied in those (rare) cases where a hang tank is used for recreational diving. Of course, the better approach is to not take divers that deep until they learn how to not chuff through their gas. Or ... if they really need to go deep ... give them bigger tanks.

... Bob (Grateful Diver)

 

[TomZ]

As a new diver, trying to learn as much as possible, I read these threads with great interest. I totally understand the necessity of gas planning, and the lack of need for hang tanks during ND diving. I can also understand the implications of perceived dependence on the practice, due to lack of proper training. The point of hanging tanks from a charter boat is well taken. All that being said... If: I hang a tank, from a buoy, on a planned ND dive, and I've planned my gas, and I've been well trained, does this mean this is a still a irrelevant practice? I understand certification agencies err to the side of caution, and may sometimes go a bit far, but really, this would be a bad thing in the event of a statistically improbable event: i.e. both divers experiencing malfunctions, or a rescue at unplanned depths such as happened in Cozumel recently (irrespective of the poor dive planning on that event, just an example)?

 

[MXGratefulDiver]

As a new diver, trying to learn as much as possible, I read these threads with great interest. I totally understand the necessity of gas planning, and the lack of need for hang tanks during ND diving. I can also understand the implications of perceived dependence on the practice, due to lack of proper training. The point of hanging tanks from a charter boat is well taken. All that being said... If: I hang a tank, from a buoy, on a planned ND dive, and I've planned my gas, and I've been well trained, does this mean this is a still a irrelevant practice? I understand certification agencies err to the side of caution, and may sometimes go a bit far, but really, this would be a bad thing in the event of a statistically improbable event: i.e. both divers experiencing malfunctions, or a rescue at unplanned depths such as happened in Cozumel recently (irrespective of the poor dive planning on that event, just an example)?

What occurred in Cozumel should not be used as an example of recreational dive planning ... it was neither recreational nor a well-conceived dive plan. If anything, it was a glaring example of what someone should NOT do. I don't think a hang tank at 15 feet would've resolved anything in this case ... by the time they got to that depth, the damage was done.

... Bob (Grateful Diver)

 

[TSandM]

In any discussion of risk mitigation, in any field, you have to consider the likelihood of the risk, the danger of the risk, the effectiveness of the proposed mitigation, and the cost of the mitigation (which can be in terms of time, logistics, money, or other things).

I can think of only one situation where a hang tank would be useful, and that is the situation where a diver has a significant decompression obligation, and does not have the gas to complete it. If the diver has run OUT of gas before he gets to the hang tank, it makes far more sense simply to surface. (Attempting to access a hang tank to do a safety stop is not a reasonable action.) To mitigate the risk involved in long deco obligations for people who haven't planned them, it is far more effective to take actions like selecting appropriate dive sites, sending divers down with guides who monitor dive time, and making sure all the divers on the boat are equipped with computers. In other words, an ounce of prevention here is better than a pound of cure . . . which puts divers at risk (since recreational divers do not have the training or experience to know how much deco they actually need to do) and screws up the boat's schedule (which didn't plan on having someone hanging for twenty minutes at the end of the dive!)

 

[cruiser]

Having never seen hanging tanks on a dive, this concept is new to me, but a logistics questions does arise within a recreational diving context. Is there a tank for every diver with their name on it? If not, what if you've exhausted your last breath to get to a hang tank and it's already in use, or someone has already sucked it dry? In which case you have to surface, which you could have done to begin with.

It just seems like a hang tank is a perceived backup that can fail on a few levels.

 

[TMHeimer]

I too have not seen tanks, etc. hung from a charter boat. On our boat here there is a bar hung by 2 ropes to assist in safety stops if many divers. There are surface "floats"-- ei, a small tube raft with a dive flag. I assume some light stuff could be put in it or tied to it (extra catch bag, light, mirror, etc.), though divers probably just take this stuff on the dive. I have never done this, but I assume such a float would be used for a shore dive when you surface swim out a ways to deep water--perhaps it would be anchored and used as a reference for ascent and if there is much boat traffic.