Calculation on having ENOUGH air for DECO

[ffdiver]

Same difference @boulderjohn. Point is to get more training.

I could have also said the IANTD advanced nitrox. Again the point is to get more training.

 

[flymolo]

OP - I see you are located on Long Island. Do you need recommendations as to a good shop for adv nitrox/decompression procedures?

I understand what you're trying to do might warrant only "light" deco, but even a difference of 5-10 minutes extra bottom time can incur a large obligation.

 

[boulderjohn]

Same difference @boulderjohn. Point is to get more training.
.

I saw your point. The difference is that Tec 40 is only one course.

 

[Captain Mikey Likey]

All legit points. I just want to be a little clearer and get some opinions. By no means will I dive into the deep end of the pool and try deco without proper training. I just thought there was a simpler formula. As for diving to 130 feet...I am comfortable diving 110 and have done numerous dives to 110. I am no means over confident but comfortable. The relief on my 110 foot dives is 70 feet. The relief on this wreck is at 80 feet...so there is plenty to see in between that.
Again I value all opinions and advice. Thank You

 

[RyanT]

Capt. Do you know your SAC? If so, you can make a fairly reasonable estimate of your gas consumption by summing together the amount of gas you consume at each depth/time point. Also, most dive planning software (e.g. Multi deco) will do it for you if you know your SAC rate.

 

[dumpsterDiver]

It is not that hard. If you want to figure a safe air supply for a short deco associated with staying too long.

You want to keep enough air in the pony to ascend safely and also enough air in the primary tank. Each should be enough to get you up without the other.

If you max depth is 130. Then assume an ascent from 140 and pick a max deco time of maybe 10or 12 minutes. This is a simple contingency for staying a few minutes too long past the no deco time limit.

If you don't know your sac rate assume 1 cuft per minute and do the math.

If you can't figure that out with a pencil and paper
Then you really, really need to take a course . The are resources on this forum that will be useful. If you are diving with a charter boat, it is unlikely they will want you doing deco without the certification.

Go.slow and there are big consequences for a math error.

 

[WarrenZ]

I would recommend that you do a few dives within the NDLs where you calculate the gas required and compare the end results of your gas you surface with to make sure that your calculations are tracking true to how you actually dive.

Dont forget to plan for a reserve quantity of gas adequate for the dive.

Also keep in mind that surfacing without completing your deco due to running out of gas can be fatal.

 

[ffdiver]

All legit points. I just want to be a little clearer and get some opinions. By no means will I dive into the deep end of the pool and try deco without proper training. I just thought there was a simpler formula. As for diving to 130 feet...I am comfortable diving 110 and have done numerous dives to 110. I am no means over confident but comfortable. The relief on my 110 foot dives is 70 feet. The relief on this wreck is at 80 feet...so there is plenty to see in between that.
Again I value all opinions and advice. Thank You

I assume you are talking about the San Diego and the Oregon right?

The San Diego does have plenty of relief and it's a great wreck to cut your teeth on. The Oregon doesn't really have relief unless you plan on just swimming around the engine near the top of it. Which is fine if that's your plan, it makes for a nice dive.
My point is that it's a really simple dive that can go to hell quickly. Just keep safe and don't worry so much about doing longer dives until you are ready to do the longer dives.

 

[Captain Mikey Likey]

I assume you are talking about the San Diego and the Oregon right?

The San Diego does have plenty of relief and it's a great wreck to cut your teeth on. The Oregon doesn't really have relief unless you plan on just swimming around the engine near the top of it. Which is fine if that's your plan, it makes for a nice dive.
My point is that it's a really simple dive that can go to hell quickly. Just keep safe and don't worry so much about doing longer dives until you are ready to do the longer dives.

Yes sir

 

[flymolo]

Multi

Yes sir

Mikey-

I have done both those dives as NDL dives. I have even gone into light deco (<10-12m) on a single 120 with an extra AL30 as bailout. Luckily nothing bad happened, but knowing what I know now, I would approach those dives differently.

My .02 is that if you are so inclined, doing some additional training will make those dives safer, with the added bonus that you get to see a lot more of the wreck.