Cutaneous Decompression Sickness

[MilitantMedic]

What do you mean my dive profile was pretty "out there". I think I was diving pretty conservatively. Most of both dives were at the 50-60' range, both included long, slow ascents with more than adequate safety stops.
First dive 60 minutes to a maximum depth of 83'. More than half of the dive between 50-60 feet. More than 8 minute safety stop.
Second dive 59 minutes to a maximum depth of 79'. Most of the dive between 50-60 feet again. At least 10 minutes above 30' and perhaps 5 minutes at safety stop depth.

Off the top of my head the NDL (PADI) for 60' is 55 mins and 90' is 25 mins. Albeit you spent more time in the 50' range. If you were to "wheel" you'll find you're very close if not over your NDLs.

I (or anyone) can safely do a 90' dive for 70 mins BUT (big but here) it's 5 mins @ 90', 10 @70', 15 mins @ 60', 20 mins @ 40', 20 mins @ 30' (and ascent) (w/SS).

That's just an example of Muli-Level planning that is still acceptable. Your dive *may* have spent too much time around 60'. If you had a computer it may have *let* you dive that profile even though you may be spending too much time.

Please understand I'm not attacking you only trying to help where I can.

 

[wylerbear]

I do dive a computer and did not come close to a deco obligation according to my Cobra which is a fairly conservative computer. Generally when I get close to the yellow zone, I ascend. Both dives, the maximum depth was reached and then almost immediately the ascent to shallower water was begun. It's hard to explain that in a simple relating of the numbers of the dive. When I spoke to the Medic at DAN, I went into greater detail about the dives and she agreed that they were pretty conservative dives. But as was pointed out-I did end up with Cutaneous Decompression Sickness so something does need to change.
I'm diving this Sunday again at a site where it's possible to go a little deep but probably will stay a little shallower, end the dive a little sooner, and extend even my usual extended safety stop. In a couple of weeks, I'll be taking the Nitrox class and hope that will prevent me from having this happen again although I will depend on more conservative profiles as a matter of course in the futrue.
Thank you all for your comments. This is great information and I'm happy to have found this resource.

 

[wylerbear]

P.S. I'm not taking offense at anything being said here, by the way. I really very much appreciate any insights or thoughts other divers have.

 

[MilitantMedic]

No prob, my suggestion would also include maybe taking a Multi-Level speciality? As well try to plan your dives so you do more "time" as you come up at each level, more or less like I posted. Mine's easy for me each time I come up 20' and add 5 mins. Just a suggestion.

Bruce

 

[Uncle Pug]

Georgia, most of our shore dives here have more to see shallow than deep. Instead of shortening your dive just extend the shallow portion.

 

[pickens_46929]

Wylerbear,

Were you using a dive computer? What make and model?

Would be interesting to know.

If you look at the tables or wheel, these profiles are indeed pushing things, but if you were using a computer, you might have indeed been showing no deco obligation. Some computers allow you to set a conservative factor which backs them off a bit, say 10% or so which can help with this.

 

[Ber Rabbit]

Thank you for your post, one of the things my OW students learn about is skin bends (among several other types). I would like to use your experience in my lecture if that's ok.
Ber :lilbunny:

 

[wylerbear]

Ber,
That's one of the reasons I posted, to help spread the information. So feel free to use the info. If you have any questions, please PM me. One of the things the DAN Medic told me is that this in not what has been known as skin bends-that's something different.
UP,
Good idea. I always spend a lot of time in the shallows anyway but spending more time there instead of shortening the dive is what I'll likely end up doing.
Pickens,
Suunto Cobra. It's about 4 years old. I can set it for a more conservative profile than I have right now. I might do that at least until I do the Nitrox class.

 

[Dive-aholic]

...I (or anyone) can safely do a 90' dive for 70 mins BUT (big but here) it's 5 mins @ 90', 10 @70', 15 mins @ 60', 20 mins @ 40', 20 mins @ 30' (and ascent) (w/SS)...

Look at your wheel again. If it's PADI's wheel, you'll see that you have to ascend to shallower than 60' if you dive to 90' - 70' isn't allowed. After 60', you have to ascend to shallower than 40'. There are no specifics on what to do after that, but you can still hang around shallower than 40' for 45 minutes and get an 85 minutes dive plus ascents and stop. Remember to check the little yellow boxes around the center.

 

[MilitantMedic]

It was actually VPM-B (off the top of my head), but you are right the wheel doesn't let you do it. I used a bad example to highlight that.