Least expensive nitrox certification option in Coz?

[halocline]

You are quite correct. But you have NO right to say someone else doesn't feel less fatigued.

I’m wondering if you have ever tried mimicking the effect of using nitrox as opposed to air in recreational diving by extending your safety stop on an air dive so that you surface with less residual N2. When I used to dive in coz on air, I would do a couple of minutes at 20ft and then at least 5 minutes, often longer, at 10 ft. Then a very gradual ascent, at least a minute to surface from 10 ft. That made a big difference in my post dive fatigue.

There’s always been back and forth discussion about the use of nitrox and pst dive fatigue, but little about simply surfacing with lower tissue pressures, which would be the logical reason for less fatigue experienced on similar profile nitrox dives.

 

[tursiops]

I’m wondering if you have ever tried mimicking the effect of using nitrox as opposed to air in recreational diving by extending your safety stop on an air dive so that you surface with less residual N2. When I used to dive in coz on air, I would do a couple of minutes at 20ft and then at least 5 minutes, often longer, at 10 ft. Then a very gradual ascent, at least a minute to surface from 10 ft. That made a big difference in my post dive fatigue.

There’s always been back and forth discussion about the use of nitrox and pst dive fatigue, but little about simply surfacing with lower tissue pressures, which would be the logical reason for less fatigue experienced on similar profile nitrox dives.

Two things: (1) it is hard to apply a "logical" reason unless one knows what the cause of the lessened fatigue is, and (2) yes, I feel better after very long safety stops, no matter what I am breathing.

 

[NW Dive Dawg]

Deleted Message

 

[BRT]

Two things: (1) it is hard to apply a "logical" reason unless one knows what the cause of the lessened fatigue is, and (2) yes, I feel better after very long safety stops, no matter what I am breathing.

Which is to say that you feel better with less decompression stress, which is why I feel better with nitrox.

 

[NW Dive Dawg]

I think that the ultimate answer to the OP's question is that it it is best to pay the very least amount of $$ necessary to get a flippn "card" that will allow you to get fills. The actual training and knowledge is 100% available and free online.

 

[wateraddiction]

I did a long safety stop (10+ min) and a very very slow ascent on my last dive and didn't feel drugged out exhausted afterwards which surprised me since I've felt like passing out everyday after just 2 dives. It prob didn't help I blew through my first safety stop on Day 1 and so the DM started adding weights to my BCD at the end of my dives.

 

[halocline]

Two things: (1) it is hard to apply a "logical" reason unless one knows what the cause of the lessened fatigue is, and (2) yes, I feel better after very long safety stops, no matter what I am breathing.

People anecdotally report feeling less post dive fatigue while using nitrox on (presumably) similar dive profiles as they would use air on. A “logical” conclusion would be to attribute that to whatever is different after the dive, and the main thing that’s really different is the amount of N2 loading upon surfacing. Is it proof…no. But it does make sense, which is just a different way of saying ‘logical.’

One could argue that another difference is the amount of N2 loading during the dive, which of course would not be affected by a longer safety stop. But since these divers are experiencing the difference in fatigue post dive, not during the dive, it’s less logical, or intuitive, or makes less sense (however you want to say it) to attribute a post dive condition to differences in tissue loading during the dive. Proof….nope, but we’re not talking about any proven cause-efffect.

You can also infer likely causation from decompression diving, where there is far more N2 tissue loading. Early surfacing of these dives causes severe symptoms, while the completion of deco schedules allows divers to surface after far more N2 loading during the dive, symptom free and without post dive fatigue. The relevance here is that this indicates that it’s the N2 loading (tissue pressure) upon surfacing, not during the dive, that is likely to be responsible for post dive symptoms, including fatigue.

I’m not trying to argue against the benefits of Nitrox; I use it all the time in cave diving. I’m just saying that I have experienced the ability to mimic the effect of lessened fatigue that is commonly attributed to Nitrox use by extending safety stops on air dives.

 

[boulderjohn]

The relevance here is that this indicates that it’s the N2 loading (tissue pressure) upon surfacing, not during the dive, that is likely to be responsible for post dive symptoms, including fatigue.

Do you mean the way a nitrox diver will have less N2 loading than an air diver doing the same profile?

 

[ggunn]

The density doesn't matter because in the context of decompression theory and practice, meters (or feet) of water, whether salt or fresh, is a pressure measurement, not a depth measurement. The algorithms and your gauges (including your dive computer) all use pressure, not actual depth. They display it in meters or feet because that's how we think, but the depth shown on your computer is just an approximation of your actual depth.

This should be somewhere on wikipedia.... Here we go:

Metre sea water - Wikipedia

en.wikipedia.org

"The metre (or meter) sea water (msw) is a metric unit of pressure used in underwater diving. It is defined as one tenth of a bar.

The unit used in the US is the foot sea water (fsw), based on standard gravity and a sea-water density of 64 lb/ft3. According to the US Navy Diving Manual, one fsw equals 0.30643 msw, 0.030643 bar, or 0.44444 psi,[1][2] though elsewhere it states that 33 fsw is 14.7 psi (one atmosphere), which gives one fsw equal to about 0.445 psi.[3]

The msw and fsw are the conventional units for measurement of diver pressure exposure used in decompression tables and the unit of calibration for pneumofathometers and hyperbaric chamber pressure gauges."

I was just pointing out that the pressure to depth relationship is dependent on the density of the water and the defining standard for the bar isn’t precisely locked to it.

 

[Sloeber]

We're here now and I was hoping Nitrox cert would be easy/economical since we could step into a shop for testing, etc. Dressel wants $260 pp which sounded high -- 2-3 hrs of elearning and I don't know if that price includes a dive but I didn't keep asking questions after I heard the price.

We're only diving twice a day (while kids club is open) but we're headed to Bonaire in Dec. If we decide to do AOW and complete dives in Bonaire, it it more economical to add Nitrox as a specialty or is there no cost advantage to adding specialty dives to AOW (does it just save time to bundle the certs)? Husband is interested in Rescue Diver option since our kids will be getting certified when they turn 10 this Dec -- but that's looking like almost 1k in additional training, does that sound correct?

Thanks for any advice, I was surprised to see how much nitrox cert cost given there's no dives required (our local shop in Chicago wants $250).

Salty Endeavors retail price is $160 for SSI Nitrox Level 2 and if you also schedule dives with us we discount it an additional 25% for $125 retail price. And you keep the textbook forever.