Turns out I'm a chicken; anybody else?

[LCF]

So, I've had a few opportunities to go down and do staged decompression dives, and I have to laugh at myself. We keep making dive plans to average 130 feet and incur 15 minutes or so of deco . . . but we get down on the dive and I keep shallowing it up, and in the end, we have little or no obligation by the time the formal "ascent" begins. I don't really do it consciously -- I'm not thinking, "Oh, dear, I don't want to be down here!" It just seems to work out that way. Sometimes I think I've just done so many multilevel dives that my subconscious is trying to create a check-mark profile without consulting me

Has anybody else found themselves doing this? Or is it just because all these dives are wall dives, so it's just easy to do, as opposed to wrecks, where you're pretty much confined to the depth where the wreck is?

[liuk3]

I think that it is natural to be conservative with obligatory deco profiles until you gain more experience and have more data points regarding how it might affect your own personal physiology. I wouldn't call it being chicken. I would call it being prudent.

[wookie]

I think that it is natural to be conservative with obligatory deco profiles until you gain more experience and have more data points regarding how it might affect your own personal physiology. I wouldn't call it being chicken. I would call it being prudent.

X2

And even on a wreck, where I have a plan for a 20 minute bottom with an alternate set of tables in case I go longer or accidentally deeper, I find myself back at the ascent point earlier than the planned time, and start my ascent. I call that live to dive another day.

[Mark Vlahos]

I don't do many deco dives that are not in a cave. Not necessarily by design, it just works out that way.

In the caves I just don't worry too much about it. I see the time getting short, then I cross the line where deco is required. I have made the plan. I have an appropriate gas waiting near the cave entrance, and I know that I could deco on back gas if it was necessary. I don't sweat it.

It is different in open water though. You have the ability to ascend. Your depth is not dictated by a rock ceiling, it is a different animal.

It does sound to me like you need to conquer the Ginnie Monster. Once you fight your way back into the system and off the main line the flow is not such an obstacle, of course that does not make the first few hundred feet any easier.

I guess it all depends on the location for the dive. A wall where there is stuff to see shallower invites that ascent. A wreck or flat bottom reef where up brings nothing but open water and an anchor line will make things easier to incur that deco obligation.

Mark Vlahos

[b1gcountry]

I'm still pretty new to decompression diving, but no. When I average shallower than the plan, I still just do whatever deco we talked about beforehand as the primary plan. I just like being in the water.

Tom

[Grateful Diver]

I often find myself beginning an ascent on those kind of dives with less deco obligation than the plan had called for. Usually it's because once I get down there I find there's more interesting stuff to look at shallower than I thought I would need to go.

It's all good ...

... Bob (Grateful Diver)

[LeadSled]

Knowing what I know about you Lynne, "chicken" is the LAST word I'd use to describe you.

[do it easy]

I ain't skeered, but we usually plan the dive to the silt. The interesting parts of the wreck are usually much higher (especially when the wreck is intact and sitting majestically as if it were quietly sailing through a soft sea of silt), so this builds some conservatism into the plan.

Chicken by design!

[JS1scuba]

The misconception among the current genre of technical divers is that decompression diving is easy. Because the procedures have been worked out, standard gasses established, and decompression tables and computers easily available the true understanding of the act of decompression has been minimized. (that's a mouthful)

"Decompression is the tax we pay for bottom time." I penned that phrase a year ago and it's as true a statement as one can make on decompression.

Having completed many thousands of decompression dives over the years I can share with you that long decompressions are usually not fun. They can be uncomfortable, boring, chilling, and at times downright dangerous. On occasion they are ok when all the pieces are in place and you can play "stupid pet tricks" with other divers around, or you get some species that decide to hang out with you. But for the most part you want it over with and back on the boat.

There are some dives where the decompression IS enjoyable as it's built into the entire dives tour. It becomes part of the multi level ascent, on walls, canyons, reefs, caves, and even on some wrecks. But again it's decompression and it prevents you from making that direct ascent.

You are not a chicken. You are working within the parameters of your mind-set and physical and emotional abilities. When I train divers for decompression we ease into it. We will begin with 15 minutes of simulated decompression, then move on to 15 min of real decompression, then 20 then 30, then 40 and so on. I limit all deco training dives to no more than 90 minutes in water. Sometimes the dive is 60 min OTB with 30 in deco and over time it moves to less bottom more deco (deeper dives) but always within that 90 min window.

Some folks have a fear that they cant hold a stop at a specific depth for a specific time. Much of that comes from not using static ascent lines. A good visual or physical reference is helpful. It helps build confidence and allows one to spend time on understanding the decompression phase instead of worrying about minor changes in buoyancy. Others are deathly afraid of decompression sickness and do not understand that bends can happen from most any dive decompression or not. (that comes back to the art of decompression)

I try to plan every dive with the least amount of effective decompression. That may mean dropping back 5 min of bottom time or by making the dive a little shallower. And, by utilizing my dive computers ability to calculate multi level dives. (great feature). One can successfully take some big dives, map them out and cut 25-40% of the decompression time off with some good multi level planning.

Are your feelings valid ? Of course they are. Don't think you can wake up one morning and decide that you can knock out 2 hours of decompression on the line. It's a hard thing to do. And, unless you have a really good reason to be doing it you are best off not to. If 15 minutes is a challenge then, again, no need to do it. Plan your dive - dive your plan. This is supposed to be fun .... right ?

(happy dance when deco is over)

Cheers
JDS

[LCF]

When I average shallower than the plan, I still just do whatever deco we talked about beforehand as the primary plan. I just like being in the water.

We have an agreement to do five minutes on O2, even if we end up without any obligation, just for the practice. But in our cold water, you don't do any midwater time for fun!

[Grateful Diver]

I dunno ... I find deco pretty relaxing. Of course, I haven't had to do more than about an hour's worth of it on a given dive yet. But it's one of the few times in my life that I get to just let both my mind and body relax. I enjoy that feeling.

Now, admittedly, if I had to do that same deco with a badly flooded suit or something, it would probably suck ... but that ain't happened yet.

... Bob (Grateful Diver)

[PeteJ]

Sometimes the tax is fun, sometimes it may not be worth the dive:

The best deco I ever had was in North Carolina when a pod of dolphins circled us for about 20 minutes and I had 3 frames left in the Nike III I had. Too bad it was 64 speed film, you need 200 or better for those guys. But back to the dolphins, there were 3 or 4 babies in the pod and I felt like the adults were showing us off to them; "Son, those are humans. Now don't laugh at them, that is just the way they are made."

The worst deco I ever had was on the wreck of the RMS Oregon when the seas went from bad at the start of the dive to "What am I doing here" by the end of it. If I didn't have two jon lines to tie together I would have dislocated a shoulder or elbow. The seas were at least 10 feet on a less then 9 second interval.

But the worst deco I never had was off of Cape Cod when the first team went in and I was all set to jump when a baby Great White showed up. It was only about 9 feet long but I didn't want to get a few "baby bites." Now the first team had a wonderful DECO watching the baby circle them for 20 minutes. It even passed between them and the boat as they were heading back to the ladder. One of the team shot out of the water onto the platform and latter said that all he was thinking was to get all of the vital organs out of the water as fast as he could.

[Benthic]

I think that it is natural to be conservative with obligatory deco profiles until you gain more experience and have more data points regarding how it might affect your own personal physiology. I wouldn't call it being chicken. I would call it being prudent.

Agreed. It's best to get a thorough knowledge of what your body will tolerate. However, it's also worth pointing out that if you plan a 130' dive for 30 minutes and then you execute a dive that's 130 feet for 15 minutes and then 100 feet for 15 minutes that is *not* a valid data point about how your body tolerates 130' dives. If you really want to learn what your body is comfortable with you need to plan the dive and dive the plan. Then, if all goes well, you can consider planning a dive that is a bit less conservative if you feel it's necessary. Personally I'm a believer in knowing the minimum deco you can get away with. That doesn't mean that's the deco I do all the time, but I have a good idea how close to the edge I can walk.

<snip>
You are not a chicken. You are working within the parameters of your mind-set and physical and emotional abilities. When I train divers for decompression we ease into it. We will begin with 15 minutes of simulated decompression, then move on to 15 min of real decompression, then 20 then 30, then 40 and so on. I limit all deco training dives to no more than 90 minutes in water. Sometimes the dive is 60 min OTB with 30 in deco and over time it moves to less bottom more deco (deeper dives) but always within that 90 min window.
<snip>

Agree very much here as well. It's best to ease into deco rather than beginning with large obligations. My first deco dives followed a progression very much like the one Joel outlines above. I also think it's wise to limit one's overall run times in certain environments. Typically in the ocean we try to limit run times to 100-110 minutes. That's mostly because you never know when weather might change, boat issues may arise, marine life issues may arise, or a host of other problems. Yes, that means that as dives get deeper they become more deco and less bottom time but, as Joel said, that's the tax you pay.

Brian

[LCF]

Well, I'm talking about very conservative dives here to begin with -- something in the nature of 130 average for 25 minutes, and thus 15 minutes of deco. I've got a personal limit of an hour in the water; although I can tolerate more, an hour's about as long as I'm at all comfortable, especially in the wintertime.

[liuk3]

Agreed. It's best to get a thorough knowledge of what your body will tolerate. However, it's also worth pointing out that if you plan a 130' dive for 30 minutes and then you execute a dive that's 130 feet for 15 minutes and then 100 feet for 15 minutes that is *not* a valid data point about how your body tolerates 130' dives. If you really want to learn what your body is comfortable with you need to plan the dive and dive the plan. Then, if all goes well, you can consider planning a dive that is a bit less conservative if you feel it's necessary. Personally I'm a believer in knowing the minimum deco you can get away with. That doesn't mean that's the deco I do all the time, but I have a good idea how close to the edge I can walk.

In your example, I would call that a dive with an average depth of 115 ft. for 30 minutes and might do 15 minutes of deco. I can still then use this as another data point in my experience regarding how my body tolerates deco profiles and practice depth averaging in order to recalculate deco on the fly. I'm still new to all this and just still trying to build up my own experience base for this type of diving. Thanks.