sidemount solo, how low is safe

[eternaljonah]

I dive Side mount and some times, on a day where the vis is above average and i'm on EAN 40 i like to stay down as long as possible, who doesn't. the question is just how low would you guys consider safe. Ocean dive never more than 20mt from the anchor line and a direct ascent is safe anyway. i need 15bar to get from 18mt to the surface including a safety stop and a make ascent speed of 9mt/min last bit at 3mt/min.
i feel safe with 20bar in each tank so a total of 40 bar to start my ascent. (though i rarely have the chance to stay down alone that long, boat want to head back before, but sometimes )
what do you all think safe or pushing the limits ?

 

[DevonDiver]

It depends on you.

 

[eternaljonah]

It depends on you.

i feel safe but sometimes its good to just see what others think about what we believe is acceptable an safe

 

[DevonDiver]

Well, it's hard for anyone to give you an affirmation, unless they've been in the water with you. So many intangibles...

From what you've written:

1) "..for as long as possible.." isn't a dive plan, nor a gas plan. Those would be a start for solo diving, at any depth.

2) Obviously, we're talking about diving within the limits of your certification (not at them), defined by your personal comfort level, current competence and accumulated experience.

3) Obviously, we're talking about no-stop dives.

4) Obviously, we're talking about a well trained and qualified solo diver.

5) Obviously, we're talking about a well trained and qualified sidemount diver.

6) Obviously, we're talking about explicit familiarity with the dive site/s concerned.

Those are my starting points as "acceptable as safe"... but just the starting points.

 

[LeadTurn_SD]

As far as "what is safe", I would first ask myself what is considered "Best Practice" for solo sidemount with the tank sizes you use, and the environment you dive in?

If you are considering deviating from what a large number of solo sidemount divers consider "Best Practice", can you clearly explain (to yourself) why? That doesn't mean what you are considering isn't "safe", but will allow you to more carefully consider why it might not be a good idea.

Or it might be fine.

I think that is part of what DevonDiver was getting at in his first reply.

Best wishes.

 

[uncfnp]

Solo is all about self rescue and redundancy, be that sidemount or pony. As a sometimes solo diver that knows little about sidemount, what are the unique considerations for a sidemount diver vs a single tank diver with a pony? Just curious.

 

[Dive-aholic]

Difficult question to answer. You mention pressure, which IMO is too low regardleess of the cylinder, but you do not mention cylinder size. Is this using an 11 liter cylinder? 15 liter? 8 liter? That makes more of a difference. Again, 20 bar is just too low regardless of how large the cylinders may be.

 

[victorzamora]

Remember that it's very common for SPG's to lose ALL accuracy at low pressures. 20bar on your SPG could actually mean 0. I wouldn't dive below 500psi/35bar at any point. Starting with your depth, you should figure out how much gas you need to ascend, do a safety stop, and then surface.....including the fudge factor for inaccurate SPG readings.

 

[Dive-aholic]

It's also common for SPGs to be inaccurate with higher pressures. Several years ago I gauged a tank with 5 different guages and had 5 different readings - 3000, 3100, 3200, 3350, 3500. Gauges are generally inaccurate and should not be thought of as anything more than a guideline.

 

[eternaljonah]

thanks
tanks are Al80's
dive plan is go down the anchor line and hang around within vis limit of it and just relax and remember there more to diving the course's and DSD's
the dive site is one i have 100's of dive's on since we do all OW, DSD's and many more dive's there, could dive it in my sleep
I have multiple dive's there where i have pushed the limit down to 30bar in each tank ( thats still more tank 50/bar together) and feel comfortable, but the other day i had a talk with one of my dive mentors and we talked about complacency and how as we dive more and more we start to feel more and more comfortable pushing limits and how its good to sometimes see if we're pushing them too far