how deep max. when diving solo?

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Unless you have a big selection of tanks on hand, like many of us DONT, you dont dive (a) SMALLER tank(s) because you dive shallower - you dive the same tank(s) that is appropriate for deeper dives.
You're not actually suggesting that people should buy smaller tanks so they can bring less gas on a dive "because thats proper gas planning"?
Don't need big selection. From more than necesary gass none died jet, but did from unapropriate dive planning which comprises gass planning.
If you do not plan your gass correctely you could be f...d off when **** hapens.
What Tony is saying is it is the same deep or shallow, gass needs to be planned corectely than you will not have problems for it, sure only saying shallow does not tell you all. You need to tel in a cave or OW, what is distsnce from shore or from entrance/exit of the cave etc...
Diving solo is a mindset not for everyone. Selfsuficience is its basic principle. Correct dive planning necesity.


Sent from my PAP4500DUO using Tapatalk 2
 
How deep do you dive as max. solo? and the max. decotime?
You have to analyze and have a Gas Consumption Plan for the particular depth you're going to. For example:

18m Beginner/Novice OW Limit

A Quick Contingency "Rock Bottom" Calculation and Gas Plan Estimate for Open Water. . .

Given a single 11 litre tank (AL80), with a standard spec of 11 litres/bar metric tank rating, and a diver's gas volume Surface Consumption Rate (SCR) of 22 litres/min -same as a pressure SCR of 2 bar/min*ATA (divide 22 litres/min by 11 litres/bar equals 2 bar/min*ATA)- using an example NDL air dive to 30m (4 ATA) depth in Open Water.

Emergency Reserve/Rock Bottom pressure calculation, from 30 meters with one minute stops every 3 meters to the surface,
-->Just "tally the ATA's":
4.0
3.7
3.4
3.1
2.8
2.5
2.2
1.9
1.6
1.3

Sum Total: 26.5

Multiplied by 2 bar/min*ATA equals 53 bar Rock Bottom absolute reading remaining on your SPG. --this also happens to be the pressure in bar needed for one person (Solo Diver) in an emergency contingency to reach the surface with the above minimum arbitrary "safety stops" ascent profile.

So ideally for a two person buddy team, multiply 53 by 2 which is 106 bar for both to reach the surface (sharing in a buddy Out-ot-Gas contingency).

But realistically, for two experienced divers stressed: 106 bar plus 30% of 106 bar equals 138 bar Rock Bottom SPG reading. (For an experienced Solo Diver, the SPG reading of the primary AL80/11L Tank would be half of 138 or 69 bar. A full auxiliary/redundant pony bottle equivalent to this amount to have along as a contingency, independent or emergency back-up would be an AL30/4.2L tank)

For two novice divers stressed: 106 bar plus 100% of 106 bar equals 212 bar (!!!) A full 11L (AL80) cylinder is 200 bar. . .
--->obviously then, two novice divers on single 11L tanks should not be diving to 30m for any significant length of time, hence the basic open water limit depth of 18m. . .

(For a novice certified Solo Diver going this deep to 30m, the SPG reading would just be 106 bar; a full auxiliary/ redundant/independent pony bottle nearly equivalent to this amount to attach along the main AL80/11L tank -or slung like a stage tank- would be an AL40/5.5L cylinder).
 
Leave it to Kev to blather mindlessly about buddy diving gas planning in a solo thread.
 
Leave it to Kev to blather mindlessly about buddy diving gas planning in a solo thread.
Hannibal . . .the prerequisite for SDI Solo Diving is an Advanced Open Water rating & certification progression from Basic Open Water Scuba --both of which initially involve the teaching and learning of Buddy Diving skills first. Do you understand? Doesn't that make sense to y'all???

The methodology for gas planning in Solo scuba is similar, except now in this instance you're only figuring out a critical amount of breathing gas just to get only yourself to the surface. . .
 
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Nah, all I need is my 19cf bottle.

N
 
Nah, all I need is my 19cf bottle.

N

Sure, fine . . . a 19cf/2.7L emergency bottle will get you to the surface from 30m: ascend at a faster rate between 9m to 18m per min to 5m depth and hold a safety stop for as long as you have any remaining gas left. However, any delay though during the ascent and you may not have any margin gas left to perform any safety stop. . .

But I prefer the slower ascent more conservative approach of post#92 above. . .
 
Sure, fine . . . a 19cf/2.7L emergency bottle will get you to the surface from 30m: ascend at a faster rate between 9m to 18m per min to 5m depth and hold a safety stop for as long as you have any remaining gas left. However, any delay though during the ascent and you may not have any margin gas left to perform any safety stop. . .

But I prefer the slower ascent more conservative approach of post#92 above. . .


Or using a 19 cu ft from 40 meters / 130 feet with a safety stop of 5 mins.... :D
 
Sure, fine . . . a 19cf/2.7L emergency bottle will get you to the surface from 30m: ascend at a faster rate between 9m to 18m per min to 5m depth and hold a safety stop for as long as you have any remaining gas left. However, any delay though during the ascent and you may not have any margin gas left to perform any safety stop. . .

But I prefer the slower ascent more conservative approach of post#92 above. . .

I am not picking on you. :wink: I enjoy your posts.

A safety stop is not a mandatory stop.

The 19cf is more than enough for me to do a standard ascent and a optional safety stop. It is unlikely the emergency will occur at the end of the dive with accumulated maximum saturation. It could but it could also occur at any point in the dive. Specifically for dives beyond 100 feet I may go with a 30cf, maybe. My SAC is quite low so giving me a little flexibility the Air Hogs do not have.

N
 
Just shy of 180' on a wreak... Did that dive 10/ 12 times ..

Jim...
 

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