Cow Springs penetration

[Tegg]

DUH!!.......

You put helium in your deco bottles?

Don't you? Hell, I even put He in my O2 bottle... I like coming out of the river in full sidemount gear with the hunter on the edge of the bank and ripping my mask off and yelling at him in my He voice... They usually only fire 2-3 shots before they get scarred and run...





[note]

Not really... I only use He when depths require it... (>150 or so, depends on dive)

[Gary]

Also, I forgot to mention that I learned kind of the hard way to surface more slowly on that HE from the ~100 dives.

"Recreational Triox" was a fad invented about 6-7 years ago using hyper-oxygenated Trimix for shallow dives for reduced narcosis. There were classes and they had their own tables.

One of the claims of those who were pushing the idea was that Triox had similar NDL's to normal air and nitrox mixes. However they failed to mention that they only achieved similar NDLs by limiting the ascent rate to 10'/min so that on a 100' dive with similar bottom time to nitrox actually required a 10 min deco. (This may have modified this later to only 10'/min starting at half max depth - so then 5 min of deco).

Also most bubble model decos assume a slow 30'/min ascent rate and then 10'/min usually starting at 50-80% of max depth until the longer stops kick in at 30-50% of max depth.

So definitely watch the ascent rates.

[Angie Reim]

Also, I forgot to mention that I learned kind of the hard way to surface more slowly on that HE from the ~100 dives.

"Recreational Triox" was a fad invented about 6-7 years ago using hyper-oxygenated Trimix for shallow dives for reduced narcosis. There were classes and they had their own tables.

One of the claims of those who were pushing the idea was that Triox had similar NDL's to normal air and nitrox mixes. However they failed to mention that they only achieved similar NDLs by limiting the ascent rate to 10'/min so that on a 100' dive with similar bottom time to nitrox actually required a 10 min deco. (This may have modified this later to only 10'/min starting at half max depth - so then 5 min of deco).

Also most bubble model decos assume a slow 30'/min ascent rate and then 10'/min usually starting at 50-80% of max depth until the longer stops kick in at 30-50% of max depth.

So definitely watch the ascent rates.

Well there you go... Anyway I do not do use trimix because of a fad. I use trimix because I get narc'd at 90'. To test it, I once stopped in the Corn Flakes on 32EAN and John asked if I knew what my deco was. I looked really hard at my dive computer and all I could say was "I dunno. Pick the biggest number to be safe?" Of course I knew the cure for narcosis was a trip to the Gallery. Since then, it's what I call the 'magic mix' for 90'+ dives. I'm a better diver and better buddy for it. 8)

[aainslie]

Something that a few computers are beginning to incorporate (like the Liquivision X1, soon to be launched) is the fact that one's ascent rate is really appropriately done on an exponential scale relative to depth. Put another way - its percent ascent/minute that really matters, not absolute ascent. So for example, at 300 ft, it's fine to go up at 60 ft/min. At 20 ft, it's nice to go up waaay slower.

Taken further, deco is only broken into "stops" out of convenience. The BEST way to do deco (ignoring the complexities of implementation) is to do the whole ascent as a continuous ascent. pretty fast to begin with and reeeeally slowly at the end.

In general, I now try to adjust my ascent rate as I go up, and start getting very cautious from about 40 feet upwards.


...Boy, this sure drifted off topic!!

[zlyrack]

Hey aainslie,

Thanks for sharing the video! I haven't been there yet so it was cool to get a preview. The quality was really good... do you have any others posted anywhere?

Thanks

[aainslie]

Thanks! Have a look at:

andrewainslie.com/page2
http://andrewainslie.com/page2.html

Or

andrewainslie.com/videos
http://andrewainslie.com/videos/

[zlyrack]

Hey Andrew, thanks for the video links... good stuff!

[andrebasso]

wow, what a great video of Cow upstream!!!

hey, what's the name of that one Dave Matthews tune? great song.....

[Gary]

The CDS site has practically lost the access rules for these sites (it took me forever to find an expired link).

Lest they be lost forever:
http://www.nsscds.org/cow.htm
http://www.nsscds.org/cathedral.htm
http://www.caves.org/preserves/ascp/mp-mcsp.html

School Sink (Wayne's World) Access Policy
School Sink is an advanced cave dive with low visibility, depths to 160 feet, and varying flows due to tidal variance. The following qualifications are required to dive:
1. Must show that they are a current NSSCDS member.
2. Must show proof of 100 cave dives, or equivalent. A cave dive is defined as any cave dive after Full Cave training is completed and greater than 30 minutes in length.
3. Must have either dove School Sink before or dive with an experienced cave diver to the system.
4. For planned dives beyond the 130 foot recreational limit, must be certified to utilize breathing gases appropriate for those depths per CDS Standards and Procedures.
5. Must hold a DPV specialty card and have logged at least 5 swim dives in School Sink before a DPV may be used in the system.
6. Those guiding may not charge any fee.
7. The site may not be used as a training site.
8. A signed waiver is required prior to diving the system. Waivers must be signed at least annually. The property manager must be notified prior to diving.
9. All dives will be planned in accordance with the contributing factors of incident analysis as published by the NSS-CDS.


I assume they are still current and the access forms still include the same requirements. Scooters are expressly forbidden anywhere at Cow.

[FW]

Thanks Gary, but it is much simpler to find them. Just go to the main NSS-CDS website http://www.nsscds.org

Then click on the "NSS-CDS Dive Sites" menu selection.