Thinking about going tec

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Depends on depth/bottom time. Get yourself a copy of MultiDeco or V-Planner and start running dives. Weak Nitrox mixes for back gas on dives 150ft or shallower with deco gas of 50 or 100%. Both are available in desktop or mobile versions. Mobile is enough to get you started, but you will likely need desktop for more functionality when actually taking your course or planning dives (lost gas, more time).

It’s an eye opener running dives you would actually do.

You like your 130ft dives. Run them with 28% back gas and see what you get.

the more deco planning and dives I did, the more I realized how much I liked carrying
2 deco gases.
 
the more deco planning and dives I did, the more I realized how much I liked carrying
2 deco gases.

From the people I’ve talked to, 50% is a common deco gas here. Either that or 100%.
 
The 130 example is because a lot of our sites are in the 110-130 range. And this where the NDL start getting short (hence why I don't usually do them). I dive because I like being underwater. A deep reef where I start at the bottom and work up (still getting 45-60minute dive) are my usual deep dives but on a wreck you cant really do that, your starting at 110-130 and working up to 90-110. Still very NDL limiting. So for the above example 2 dives at 130 with N28 is 36 minutes of total time. If tech let's me get say an hour of total it's worth it to me.
 
The 130 example is because a lot of our sites are in the 110-130 range. And this where the NDL start getting short (hence why I don't usually do them). I dive because I like being underwater. A deep reef where I start at the bottom and work up (still getting 45-60minute dive) are my usual deep dives but on a wreck you cant really do that, your starting at 110-130 and working up to 90-110. Still very NDL limiting. So for the above example 2 dives at 130 with N28 is 36 minutes of total time. If tech let's me get say an hour of total it's worth it to me.

Bottom time really hinges on how much deco you are willing to do. Off to run a dive on MultiDeco. Be back shortly.

OK, I ran 130ft dive for 60 min with 28% back gas. I did it 3 times, with 50%, 100%, and with both 50 and 100 as deco for the same dive. Should be eye opening for you. O2 exposure is a real issue.

BAC93CC3-0055-4850-AC56-9E1922140EC8.png
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Please consider gas density issues when you go deep. I heed Dr. Simon Mitchell's recommendation of a 5.2 g / L.

Alert Diver | Performance Under Pressure
 
The 130 example is because a lot of our sites are in the 110-130 range. And this where the NDL start getting short (hence why I don't usually do them). I dive because I like being underwater. A deep reef where I start at the bottom and work up (still getting 45-60minute dive) are my usual deep dives but on a wreck you cant really do that, your starting at 110-130 and working up to 90-110. Still very NDL limiting. So for the above example 2 dives at 130 with N28 is 36 minutes of total time. If tech let's me get say an hour of total it's worth it to me.
Assuming you have some decent sized doubles and a 40 of deco gas.
30mins @ 130ft is going to incur about 20-25mins of deco. So just under an hour runtime.
You could in theory do 2 of those with a 2hr SI.

60mins at 130ft is not really an entry level AN/DP type dive. You're just under an hour of deco which is quite a bit when you are still building your experience base. It's also requires a lot of bottom gas and hefty reserves to handle OOA and other contingencies.
 
Assuming you have some decent sized doubles and a 40 of deco gas.
30mins @ 130ft is going to incur about 20-25mins of deco. So just under an hour.
You could in theory do 2 of those with a 2hr SI.

60mins at 130ft is not really an entry level AN/DP type dive. You're

So it is worthwhile to pursue, I have doubled my bottom time and almost 4 times total in water.
 
Assuming you have some decent sized doubles and a 40 of deco gas.
30mins @ 130ft is going to incur about 20-25mins of deco. So just under an hour runtime.
You could in theory do 2 of those with a 2hr SI.

60mins at 130ft is not really an entry level AN/DP type dive. You're just under an hour of deco which is quite a bit when you are still building your experience base. It's also requires a lot of bottom gas and hefty reserves to handle OOA and other contingencies.
I’d agree for sure.
An hour at 130ft gives me 53 min of deco with 50 %and 100% while ANDP has no deco time constraints its a fair amount of deco to do. I think you need to work your way up to that kind of deco obligation.
On my course dives we usually did 30-40 min of deco as practice while incurring 5-20 min of actual deco obligation
 
This is that same 130ft dive on AIR with 50 and 100 for deco gas and just 50%. You get a CNS warning for just 100 for deco on this dive.

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https://www.shearwater.com/products/teric/
http://cavediveflorida.com/Rum_House.htm

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