SDI specialty training for solo diver

[scubadada]

I am slinging a 30cu Catalina. I will usually surface with 500 ish psi in my main, after doing a 3 or 5 min SS. If I hit 101'+, my Shearwater automatically goes to a 5 min SS, and I keep that in mind, when deciding to surface. 99% of my diving is shore diving. If I am diving with a buddy, I will usually come up sooner, due to "rock bottom" gas needs. Once again though, the pony is not included in gas planning.

Better yet, use SurfGF to end up with the surfacing GF of your choice,

I used an adaptive-like stop strategy before I bought my Shearwater by lengthening my safety stop if I closely approached NDL and to pad my last stop for light deco. Since buying my Teric in May 2019, I have not surfaced with a GF higher than the low 80s. My average surfacing GF for those nearly 500 dives is around 50. I do at least a 3 min SS for all no stop dives, regardless of my SurfGF, just because.

 

[Gandalf-the-Diver]

Better yet, use SurfGF to end up with the surfacing GF of your choice,

I used an adaptive-like stop strategy before I bought my Shearwater by lengthening my safety stop if I closely approached NDL and to pad my last stop for light deco. Since buying my Teric in May 2019, I have not surfaced with a GF higher than the low 80s. My average surfacing GF for those nearly 500 dives is around 50. I do at least a 3 min SS for all no stop dives, regardless of my SurfGF, just because.

I have only been diving for 2.5 yrs, and really don't feel I have had the training, to start using GF, or to customise the GFs in my Peregrine. I have set the conservatism to low, however, and been known to ride my NDL. At this mornings dive, my buddy and I were discussing this very topic, as his Perdix, is set to medium. He ran out of NDL time, while I was still at 4 min to NDL. We were at 101'.

 

[scubadada]

Hi @Gandalf-the-Diver

So, you are diving a GF high of 95. I also dive a GF high of 95, but have chosen to dive a different GF low rather than the preset default of 45. The SurfGF is really rather simple, it tells you your surfacing GF if you instantaneously surfaced at that time. If you look at it at the end of your safety stop or at the end of your deco stop, it will give you a surfacing GF that will be just a little high, reduced a bit more by your final ascent to the surface. You can use this to choose your surfacing GF from a dive.

In the graph, the GF (GF99) was 1% at the start of the ascent, it was 14% when arriving at the safety stop and 11% at the end of the safety stop. At the surface it was 74%. By looking at SurfGF at the end of the safety stop, you would know that your surfacing GF would be in the low 70s, despite the significant blooming of the GF on final ascent.

 

[neeka]

I think it's interesting that in Tech diving which is more advanced is a solo kind of affair. I guess with recreational diving you have someone to buddy breathe with for certain situations. this is a topic I will investigate further.

 

[Marie13]

I think it's interesting that in Tech diving which is more advanced is a solo kind of affair. I guess with recreational diving you have someone to buddy breathe with for certain situations. this is a topic I will investigate further.

Buddy breathing is no longer taught.

 

[neeka]

Buddy breathing is no longer taught.

do you mean in Solo courses or OpenWater ?

 

[Marie13]

do you mean in Solo courses or OpenWater

OW.

 

[BlueTrin]

Buddy breathing is no longer taught.

Except in some technical classes to share deco gas (which is exactly what you said: it’s no longer taught in rec classes)

 

[Marie13]

I just completed the E-Learning portion of the SDI Solo course, there is added emphasis on gas planning and it is clearly more stringent than normal buddy diving. The SDI course basically "requires" a strong adherence to a strict "rule of thirds" which means on a dive with a single back mount AL80 with a starting pressure of 3K psi that "the course" wants me back at my safety stop with 1000psi. I normally plan to be at my SS with 500psi. I also note that the site conditions can come into play. For example on Bonaire on the far south end dives with longer shallow water swim outs to the drop off, I may arrive back to the top of the drop off with 500psi and then spend another 5 to 10 minutes on the bottom navigating back to the truck.

We're all gonna end up doing what we feel is best for us........But..... for the SDI course, I'd plan to be at my SS with 1/3 gas remaining..... And also note that redundant gas does not factor into the rule of thirds.

I’m used to the rule of thirds from OC cave diving, so that’s what my “muscle memory” is used to, so that’s what I use OC. Always on SM for OC. My solo dives are always pretty shallow anyway, less than 30ft. I get bored long before gas rules are an issue.

 

[rx7diver]

Buddy breathing is no longer taught.

My daughter's open water course last year, a university NAUI course, taught buddy breathing.

Personally, I think buddy breathing is a valuable skill to have, another option divers "should" have in their toolbox. Just in case.

rx7diver