Scooter Free Diving and DCS

[ricki]

Electric dive scooters can extend dive duration and depth range substantially without much difficulty. They can also increase the quantity of repetitive dives as well. As easy as scooter diving can be, it is best to try to observe a policy from kiteboarding. Never go further (deeper or longer in this case) than you are willing to swim back from on your own. I did 8 to 10 shallow scooter dives to 100 to 115 ft. for fairly short intervals usually under 2 minutes wreck of the Spiegel Grove off Key Largo, FL, USA. I started to think about possible DSC with repetitive dives after the first couple and increased my surface interval to 10 minutes or longer. Aside from increasing surface intervals and checking some posts on this subject today, slowing ascent in the upper 33 ft. and even stopping, are there other suggestions out there? I had no symptoms of DCS not even untoward fatigue. I had the misfortune to have a number of minor DCS hits starting at 16 years on SCUBA and again during Trimix diving in the early '90's, so the symptoms are familiar.

[Jon]

At the end of a long day of scooter diving I'll go back down with a stage of 02 and deco out for the day. I don't do this in the middle of my diving, just at the very end of the day when I'm done.

Other than that, I do the same things you mentioned- extended surface intervals between dives. Scooter diving is so relaxing that is lulls you into doing longer/deeper dives without prolonged surface intervals because your not winded. Using a watch to time surface intervals is a must- which your already doing.

One thing I just switched to, thanks to Longfins, is a climbing harness to hook my scooter into. I used to use a standard weightbelt, with a DiveRite scooter strap, but the harness is much more comfortable and gives me more places to hang things off of- like cameras. It also allows me to drive the scooter with one hand while I clear my ears with the other. Or, if you can clear your ears hands-free like Peter does, you can run the scooter with one hand while you shoot video with your digital camera in the other. You can pick a cheap harness from REI for less than $35.

Jon

[ricki]

Doing O2 deco makes sense, thanks for mentioning it. The climbing harness is a good touch. I am currently using an inexpensive SeeDoo with minimal thrust, so equalizing while wedging it between your arm and one hand is not hard. I had doubts about it's usefulness but learned it is adequate for some applications this weekend.

I had an old Tekna with a lot more thrust, so much that I used a tee seat (didn't like using a Spanish Bowland for dropping off quickly) when free diving to ease arm fatigue and allow ready equalization. I had to retire it after the third rebuild, too bad, it was a nice ride.

So, what do you think about a minimal 10 minute surface interval between dives? A longer break when changing out batteries if possible could be done as well. O2 deco at the end of the day or sooner with more extreme exposure. You could pause at 15 ft. for a safety stop and go real slow up from 33 ft.. Other ideas or experiences with this?

Thanks!

[Ale Andres]

There are Deco tables for apnea, i don't have it her but surely you can find it if you search in the web

[ricki]

Originally Posted by Ale Andres

There are Deco tables for apnea, i don't have it her but surely you can find it if you search in the web

Thanks, found a table on this site at the link:

http://forums.deeperblue.net/attachm...earfishing.pdf

Question, is the traditional definition of bottom time used in this case, that is the time from leaving the surface to start of ascent or does it include the entire time immersed?

Looks reasonable but I wonder what decompression algorithm and empirical testing the table is based upon?

One direction would be to go to a free diving deco meter such as is under discussion at: http://forums.deeperblue.net/freediv...suunto-d3.html

Looking into the Oceanic Geo now. Even with that though precautions for reducing residual nitrogen in apnea make sense. Other ideas out there?

Thanks