Tech 40 with a Pony Bottle?

[GeoffreyD]

Hi all,

First post here. Please be gentle ...

Anyway, I was looking at a thread and came across Andy Davis article where he compares the PADI Deep Diver course with Tech 40. In outlining the equipment options he refers to single back-mount with appropriately sized pony bottle as an alternative to double back-mount or side-mount (or double valve single).

This would suit me well as I already have most of this equipment and its what I plan to dive with in the future in the context of solo diving (not deep, no deco, no overhead). My tech ambitions are negligible but I am interested in the theory, planning and other skills in tech which carry over to sport diving.

So, what do people think about the idea of doing tech 40 with single back-mount and slung bottle?

 

[PfcAJ]

Sounds like nickle rocketry and half way garbage to me

 

[joe8mofo]

Doesn't meet the requirements for Tech 40 gear. At a minimum you would need your single cylinder to have an H/Y valve to meet redundant regulator requirements.

Tech 40 is a complete waste of time because you are only allowed to use 50% and only deal with 10 minutes of Deco.
Go for TDI Advanced Nitrox and Deco and you get 100% O2 and 10 minutes isnt a limit. I am finishing my AN/DP currently, have 2 more dives to go until completion.

 

[uncfnp]

Hey @GeoffreyD.

Not so long ago I explored similar options with various instructors. Even discussed it here on SB and received similar "encouragement."

At that time it seemed to really be up to the instructor. In my experience most instructors want the full package, doubles. But if you can find an instructor willing to work with you and your goals my understanding is that it will meet the PADI requirements.

• Any one of the following appropriately labeled and marked options:
  • A single cylinder with a dual outlet valve (eg H valve or Y valve).
    
    
  • A single cylinder with single outlet valve and a pony bottle. Pony bottle should have same gas as main cylinder, or be breathable at the deepest planned dive depth. The minimum size cylinder is one with a free gas capacity of 30 cubic feet.
    
    
  • Back mounted doubles with dual isolator manifold
    
    
  • Two side mounted cylinders (sidemount configuration)

FWIW I think this is a good option for divers wanting an introduction to more advanced diving or just wanting to make their recreational diving a little safer and start approaching thier dives with a "technical mindset."

 

[Diving Dubai]

Tech 40 is a complete waste of time because you are only allowed to use 50% and only deal with 10 minutes of Deco

Seriously dude

Tec 40 is an "intro" course. It where you learn theroy and procedures and get your technique squared away.

It's irrelevant that you're only doing up to 10mins deco with upto 50%. What you're learning and practicing is procedures and deco theory. Most candidates won't have even slung a deco cylinder before...

For the record. BSACteach backgas deco on their second tier course (AOW) in PADI terms. Because you're still restricted by their OW CERT depths, they never actually go into deco, which doesn't matter. Their simulation still makes sure they can plan the dive, hit all their run times and hold stops to the prescribed limits.

Baby steps....

 

[divezonescuba]

You also have to use a deco cylinder during the TEC 40 course. It is recommended that each student have their own, but sharing is permissible according to the standards document. I would want each student to have their own.

So if you used a single primary cylinder and a pony bottle, you would have to either sling two cylinders or have the pony bottle attached to the primary cylinder and sling the deco cylinder.

Slinging two cylinders is better left to TEC 50.

 

[boulderjohn]

You also have to use a deco cylinder during the TEC 40 course. It is recommended that each student have their own, but sharing is permissible according to the standards document. .

Correct, but it can only be shared for practice sessions, in which they case they would be taking turns. On a real dive, each would have to have their own deco bottle in addition to whatever they were using for redundant back gas.

 

[divezonescuba]

Yes, I don't know how you would really be able to do any training dive sharing a single deco bottle unless it was for an emergency exercise. Better to just have one per person for the entire course.

 

[boulderjohn]

Yes, I don't know how you would really be able to do any training dive sharing a single deco bottle unless it was for an emergency exercise. Better to just have one per person for the entire course.

I agree.

I guessing what they have in mind is something like I do for dive #1 for trimix when I have more than one student. They have to carry, stage, unstage (etc.) 4 deco bottles as one of the exercises. I don't have them all carry 4 deco bottles throughout the dive. When it is time for them to do those exercises, I have them take turns with the 4 bottles I bring.

I don't see a good reason for doing it in Tec 40, though. It seems to me they need to get used to carrying the deco bottle, and since they will need it in the real dives, they might as well get used to it from the start.

 

[raftingtigger]

I did my Tec40 with a backmounted HP100 and single long hose. I had a OPV on the 1st stage and a inline shut-off on the 2nd stage. My second tank was a SM 80 with short hose. A 30 cuft pony would have been sufficient. Absent a 1st stage failure I had access to all my gas with a freeflowing 2nd stage on either tank. I do not have the strength to carry doubles, no interest in them, and can't reach a backmounted valve. This was a very workable solution for me at the time. FWIW, I have moved on to full SM.

My reasoning for taking the class was the same as the OP's. I don't intend to go deep, or more than touch on any deco. It was the theory and the observed practice I was after.