Nitrox in Cozumel

[fred3798]

We're going to Cozumel and expect to dive 2x per day for 6 or 7 days. Maybe throw in a night dive or a shore dive too. Lots of surface intervals and no heavy multi-dive days. We have 50 dives each and in our last trip we found we neared our NDL well before we ran out of air. So our DM suiggested we try Nitrox. We've done the (simple) on-line course. So, I understand that we might feel better (which is unproven) and at moderate depth we can increase our NDL. But a lot of the dives in Cozumel seem to be in the 80-100 foot range. Isn't that nearing a problem with Nitrox?

Do experienced divers always use Nitrox when available? When do you prefer it or prefer to avoid it? What say ye all?

Thanks

 

[Bubbletrubble]

Nitrox will give you more bottom time for dives in the 60-100 fsw range.

However, given your "light" dive schedule, using regular air should be sufficient. You'll have ample time to off-gas from day to day.

If you aren't convinced, by all means, dive nitrox. It's your vacation.

In general, I like to use nitrox when I'm on a multi-day repetitive (3 or more dives per day) dive trip. FWIW, even if I'm using nitrox, I try to schedule a non-diving day in the middle of a dive-heavy trip to allow my body to off-gas and recover.

Using nitrox on a Bonaire trip is a no-brainer. For most of the unlimited shore diving packages on the island, there is no additional charge for using 32% nitrox.

I wouldn't hesitate to pay for nitrox on a week-long liveaboard trip. Money well spent, in my opinion.

For the local diving that I do (typically single night dives with max depths ranging from 60-80 fsw), I don't bother using nitrox. Depending on the multilevel depth profile our group chooses, I can usually manage a 100-minute dive with my HP100 tank. That's more than enough bottom time for me.

 

[beaverdivers]

But a lot of the dives in Cozumel seem to be in the 80-100 foot range. Isn't that nearing a problem with Nitrox?

It depends on your Nitrox mix? If you are diving 32%, then your Max Operating Depth ( MOD ) is 130' at a PPO2 of 1.6, Max. Depth Limit. You have a 30' buffer.

Do experienced divers always use Nitrox when available?

Yes, smart ones do.

When do you prefer it or prefer to avoid it? What say ye all?

Thanks

I always dive Nitrox, just different mixes depending on what I want my MOD to be.

Realize Air is a 21% mix of Nitrox.

 

[boulderjohn]

When I dive in Cozumel, I use nitrox quite a bit, and I have found the attitude toward it is beginning to change there. When I say "beginning," I have to admit that I have not been there in two years, so it may be even more different.

The first time I asked for nitrox on a dive (EANx 32), which was many years ago, the DM would not let me use it on the first dive, saying it was too dangerous. He said it could only be used on the shallow second dive. That was absurd. He assumed I might not hold my buoyancy properly on an 80-100 foot dive and might instead plummet to 130 plus and stay there long enough (which is considerable) to have a problem. A number of Cozumel operators used to have that attitude--nitrox only on the second, shallow dives.

Since then, on all my trips I have used nitrox quite a bit. (I switched to a different operator with a different attitude.) In all my diving wherever I go, I use nitrox on all dives between 70-130 feet whenever I can.

That is because, in part, I know that my breathing gas will last longer than my NDL. If you are going to run out of air before you reach your NDL, then there is really no point to the nitrox. Otherwise, the typical 80-100 feet depth of a typical Cozumel first dive is ideal for nitrox.

 

[beaverdivers]

That is because, in part, I know that my breathing gas will last longer than my NDL. If you are going to run out of air before you reach your NDL, then there is really no point to the nitrox. Otherwise, the typical 80-100 feet depth of a typical Cozumel first dive is ideal for nitrox.

Yes, it is even MORE important that you use Nitrox because the diver that is using his gas faster probably has increased workload, therefore increased nitrogen load.

The only way to keep track of increased workload is to use an Air-Integrated dive computer!

 

[boulderjohn]

Yes, it is even MORE important that you use Nitrox because the diver that is using his gas faster probably has increased workload, therefore increased nitrogen load.

The only way to keep track of increased workload is to use an Air-Integrated dive computer!

What's interesting is that you said that in another thread and I asked for more information. You chose not to reply.

Could you please explain your point, because most people do not believe this is true.

 

[Woodiver]

If we're on a liveaboard that offers nitrox, it's a no brainer to opt for nitrox. With day operators, you need to decide what works best for you. The profiles in Cozumel can push you into deco on a two tank day which isn't a big thing, it really depends on the sites, the number of dives per dive and your SI's. We have done northern sites which can be square profiles where nitrox is a real benefit and can double your bottom time. In Cozumel we normally opt for air on the first dive and 36% on the second dive, I'd rather be safe than risk getting bent. We know too many people have been bent even though they did everything correct.

 

[beaverdivers]

What's interesting is that you said that in another thread and I asked for more information. You chose not to reply.

Could you please explain your point, because most people do not believe this is true.

It is simple > workload means >Nitrogen. Do you believe it is true?

 

[Mayor]

Two dives a day maybe three over a week you can be sure I'm using Nitrox.

 

[Bubbletrubble]

It is simple > workload means >Nitrogen. Do you believe it is true?

:blessing:
@beaverdivers: Are you an instructor?