Any danger from several shallow dives in a row?

[pt40fathoms]

It sounds like your dive profile, although unconventional and not recommended, was not completely dangerous due to the shallow depths and short dive times. However people have had DCS hits doing the most benign dive profiles, those events are referred to as “undeserved decompression sickness”, and tend to defy explanation. The key to keeping yourself safe, is taking precautions that lessen your chance of a DCS hit. Drink lots of water the day before and the day of your dives. This is the one key area that most divers tend to slough off and treat with the least amount of respect. It is also the one item entirely in your control that will do the most in keeping you healthy, so keep hydrated. Ascend slowly from every dive. The shook up pop bottle is the best visual description for this. You can open the pop bottle without it exploding in foam, as long as you open it slowly. So ascend slowly from every dive and keep yourself from producing bubbles. Have a minimum surface interval of 1 hour between dives. This is not to say that when you come up from a shallow depth to get a bearing to shore, you cannot go back down to that shallow depth. In that instance you are simply continuing on with the same dive, just make sure you ascend slowly when you need to get your bearings. But after the dive, take your time and relax, stay on top for at least 1 hour. Now onto exertion after the dive. Don’t lift weights, run a marathon, chase cats, or go bull riding, and on the other end, don’t go to sleep or lay down for the entire hour either. Keep active, but keep it light and relaxing.

Now go out and log some easy dives, and have fun with your daughter. The cherished memories you make will be worth it.

 

[Dive-aholic]

Beg to differ. You can spend several hours at shallow depths with little risk ... assuming that you ascend properly. People sometimes get bent coming up from depths as shallow as 20 fsw by making rapid or repeated ascents ... instructors doing repeated CESA's with their students, for example.

Even a little bit of nitrogen coming out of solution as you ascend can bend you if the bubbles expand quickly enough. The problem isn't totally due to the amount of nitrogen in your system ... it's also due to the probability of those tiny nitrogen bubbles colliding and combining. The more quickly they form and expand, the greater the possibility of that happening ...

... Bob (Grateful Diver)

I'm totally in agreement. That was already covered in regards to the fast ascent on one dive so I took it for granted that it would be understood. Should have mentioned it, though. :11:

 

[puk00puk00]

I was requesting advice on 2nd stages in shallow dives and fell into this related topic so relevant to my dive profile (not sure how i might be "feeling" (future) if hadn't fallen into this thread!!!)... this is just a thanks to the Jared participants and copy of my addition to my reg thread.



I just skimmed thru the thread below (sawtooth dive profile) and though it's clearly off the reg topic, decided it needed to be attached to my equipment thread since the shallow dive sawtooth profile could easily be ignored or totally missed by a newbie reading my shallow dive thread. The read totally got my attention since it applies directly to my situation. Once again, I am appreciating that shallow dives are to be treated with the same respect as deeper work.

ScubaBoard > Scuba Diving Central > Basic Scuba Discussions
Any danger from several shallow dives in a row?


So, my thanks to Jared’s informant’s to get the sawtooth issue out on the table. Chuck (puk00puk00)

 

[alibee]

Just to pipe in...

Right before I was OW certified, I was speaking to a friend's mom about my interest in diving. She was telling me how dangerous it was because she got DCS while at a resort, and she made it sound like it was really random that this happened to her, so I asked her what she had been doing. Apparently, she lost her dive buddy and was going down to 10'-15', searching around for a few minutes, ascending to the surface, looking around there, then descending to 10'-15' again, over and over again (5+x).

After my certification, I had to keep myself from calling her up and berating her:
- Obviously, the dive profile there is just... not in line with anything you learn in an OW class.
- OW teaches to only search for our buddies underwater for 1 minute and then permanently ascend, so you have a greater chance of find each other.

Argh. At least some of us pay attention!

 

[JimC]

Just to chime in, bounce dives, even shallow ones are a recipe for disaster.

Do a proper accent, do some surface time. Even a dive to 30 foot dive deserves a safety stop at 15-10 feet.

 

[miketsp]

See this reference
http://www.scubaboard.com/showpost.php?p=904520&postcount=5

 

[baitedstorm]

Here's a great way to get your daughter more comfortable in the water (and also the exact thing I still do with my girls ages 9 and 13)

Go down to WalMart and in the toy section you should still be able to find their seasonal swim stuff.. They actually make a few different packages of sinkable pool toys that look like shells, coral, and little fish. Buy everyone different one you can find (I found 3), take your little one to a swimming pool and go dive. I spend time at the bottom of the pool with my girls just hanging there, doing nothing (cept watching like a hawk.. ). I hand them the different reef like toys for them to inspect (and completely relax them).. Before you know it, 20 minutes has passed then we work on skills. It will probably be at least another year before I let them out of the pool so I'm constantly looking for ways to entertain them. Sometimes I'll hide treasures for them, if they find them, they get to keep them.. I even give them a little treasure bag to stash their finds in, kinda makes it more offical. The underwater cameras were also a huge hit.. I never knew just how much gunk a pool can actually have.... lol..

Your daughter isn't capable of being your dive buddy right now, nor will she for several good years. I LOVE that you have her starting young, just remember to make it all about her when she's diving with you.
Just my opinion, when she can dive around the pool without a mask and still breath comfortably underwater, she's ready for the next level. That being said, have fun with her, take a ton of pictures of her underwater and make her a photo album. She will start to identify with being a diver (should she actually want to dive) and crave the pool adventures you create for her..

Cheers,
Vickie

 

[jaycanwk]

Some good advice so far. I would only add that maybe you should zero in on the reason she is feeling uncomfortable and wanting to go up so often. If you two can work through that, then the saw tooth profile won't be an issue as she will stay down the whole time. She might be cold or a bit nervous etc.. Maybe try a location with better visibility or not as cold or a shallow shipwreck or something else to see.


JASON ~~~

 

[Sideband]

Also one detail I left out that my brother would like me to mention, he was there with us. He's been diving for a couple of years and has around 20 dives under his belt I believe. So it wasn't just my daughter and I alone the whole time. We were diving with a more experienced diver at the time and plan to do so going forward if/when she does more open water dives.

Be careful here. My intent is not to cut on your brother at all but "more experienced" is a very relative phrase. IMHO, 20 dives, especially over a period of several years, is very little experience. Now, your brother may be Aquaman for all I know so take from this what you will, but while 20 may sound like a lot to someone new it really isn't very many. Even if it is only over 2 years that's only 10 dives a year. There is nothing wrong with that at all but it doesn't make for a good safety diver. I was still working out my own issues even after that point.

Joe

 

[LJinFLA]

This is very interesting thread to me because i have just recently gotten into lobstering. I have hooked up witht some very experienced divers. they are all DMs with hundreds of dives under their belt. The one that taught me how to hunt the bugs gets a commercial lobstering license so that he has no limit and he seems to know his stuff. We basically hunt bugs in 70 to 90 feet of water and his instruction is that we travel at 15 to 20 feet above the botton until we find likely spots for bugs and then rapidly descend to the spot, pull out the bugs and go back up 15 or 20 feet and move on until we find the next spot. The resulting profile is definately a bit sawtooth. They are a few minutes at the bottom hunting out the bugs, and then back up for a few more yards and then back down to pull out the bugs. It is a great system for getting bugs because it makes better use of your gas. Since less gas is used at 70 feet than at 90 we can stay down longer and get more bugs.

After reading this, I am a bit concerned about the sawtooth nature of this profile. We make a slow and measured ascent when we do surface, we do our safety stops, and we are diving nitrox, but is this still dangerous?

LJ