Question How to dive nitrox for the first time

[TravisD]

...some places will have an analyzer station set up somewhere and point you to it. It's unlikely that they would have staff accompany a certified (nitrox) diver, but if you ask for help they probably would send someone to help you out. Couple of places I've seen will have analyzer info in an Intro video that you can watch before you get there, or possibly may do so as part of their intake process.

 

[tursiops]

If it's a mixed gas group led by a DM and all divers must surface together, and do the same surface intervals then Nitrox is almost pointless.

"almost pointless"? In the situation you describe, you do not get more bottom time or shorter surface intervals, but you DO on-gas less N2, and many feel that is good.

 

[boulderjohn]

Like is the DM going to lead me to my tank and give me an analyzer so that I can do the checking?

I think I have seen every procedure imaginable. The one you don't want to accept is the one where they tell you what is in the tank and expect you to accept it without checking it. I have had that happen more than a few times, and I simply tell them I want to check it myself. They always produce an analyzer.

 

[Blackcrusader]

I’m going to Moalboal, Oslob and Malapascua. They are not going to be too deep that’s why I plan to dive on Nitrox.

Dives on the walls in Moalboal and also at Pescodore island do go to 40m for recreational divers.
Some guides do prefer not to exceed 30m on dives depending on the dive op. I have done many dives 35-40m depth in Moalboal. I was there for two weeks in February and again two weeks in March this year.

When I dive on 32% I set I try to limit my depth to 30m and do not push the MOD of 34m.

On most my dives the guides and other divers were on 21%. This just meant that as they needed to ascend due to NDL I would just continue the dive at around 20m depth or a bit deeper and then ascend near the end of the dive. This let me enjoy being on my own chilling out with the other divers just above me.

@ttc008 When you ask for Nitrox you need to analize the gas mix on your tank and make sure you set your DC to that mix. Always check the mix yourself. In fact where I was diving with Savedra in Moalboal you cannot take a nitrox tank without you first checking the mix in front of the staff, and writing the date, your name, cert level, gas mix and gas tank pressure in the shops nitrox log book. Then the tank was labeled with your name and the had mix on it. Although 32% is the standard mix sometimes you get 31.5% but you can also ask for 40% or 25%

Nitrox just allows you to stay deeper for longer but that means using more gas. It won't give you a longer total dive time. Recently I was diving where the dive op sets dives times at 60 minutes with 90 minute surface intervals between the morning dives and a 2 hour interval before the afternoon dive.

I am an experienced diver and use less gas than even the guides I was diving with. So I am about to utilize my nitrox mix and only ascend to a shallower depth when my NDL was at around 2 minutes.

Do pay attention to your SPG and to your NDL and enjoy your fun dives. Also upload your dive logs so you can review them after dives.

 

[Blackcrusader]

It is very relevant in recreational diving. If your buddy is on air and you are on nitrox, you need to discuss no-stop times. You don’t want your buddy to shoot to the surface because OMG their computer showed 1 minute of deco while you were at 15 minutes NDL.

Why would your buddy shoot to the surface and end the dive just because they had 1 or a few minutes of Deco time on their DC? Deco obligation will clear on the dive as they ascend to shallower depths without needing to end the dive. Of course better not to have unplanned deco and also be trained for deco and understand your DC as well.

 

[lowwall]

Many might feel that way but so what? Many people feel the earth is flat too.

Except we know the Earth isn't flat.

We don't definitively know if N2 loads that are somewhat less than those required to cause clinical DCS symptoms can cause or exacerbate other conditions. But we do know that DCS is not a binary condition, it gets worse as N2 loadings increase. So it is not illogical to posit that this continuum also exists at loadings below whatever point we decide constitutes clinical DCS.

Edit to add.

A quick search finds that there is at least preliminary evidence to suggest fatigue is ameliorated when using Nitrox versus air. Fatigue is likely to be a marker of some sort of decompression stress.

Also, use of Nitrox appears to result in clearer thinking which could certainly be useful in an emergency.

 

[babyhippo]

In fact where I was diving with Savedra in Moalboal you cannot take a nitrox tank without you first checking the mix in front of the staff, and writing the date, your name, cert level, gas mix and gas tank pressure in the shops nitrox log book.

On most my dives the guides and other divers were on 21%. This just meant that as they needed to ascend due to NDL I would just continue the dive at around 20m depth or a bit deeper and then ascend near the end of the dive. This let me enjoy being on my own chilling out with the other divers just above me.

That seems like good practice by Savedra. I know Savedra is a popular shop there. Are you saying even with them there most likely won't be enough nitrox divers to form their own group? Did you have to communicate to the DM beforehand that you will probably ascend later than others and the DM was ok with it? I imagine the DM would come back to find you after everyone else has surfaced?

 

[Blackcrusader]

That seems like good practice by Savedra. I know Savedra is a popular shop there. Are you saying even with them there most likely won't be enough nitrox divers to form their own group? Did you have to communicate to the DM beforehand that you will probably ascend later than others and the DM was ok with it? I imagine the DM would come back to find you after everyone else has surfaced?

Divers choose what gas mix they want. One of the staff is not nitrox certified or a DM yet. So they let him dive with me as my "guide" to let him get some experience with me. So really I could just dive as I want. Great young lad but not too good on gas consumption. At times I was with guides and divers on nitrox. At other times I was on nitrox with a guide and diver not on nitrox. Yes the guides are advised I will remain deeper as they ascend. By the time I was doing these nitrox dives the guides had been diving with me for over 3 weeks so as a known experienced diver they don't need to be concerned about me. One one dive with a regular dive buddy the guide took the divers deeper and my buddy and I headed off on our own dive but stayed shallow around 12m - 15m for the dive. This was pre planned but it was the first time for the DM to have had two experienced divers head off on their own and meet up at the dive boat at 55 minutes for the safety stop.

PS We did the safety stops together on the dives. Just because I stayed deeper for some part of the dive does not mean that the safety stop is not done together. If you see my dive log post you see that after 50 mins I come up to around 10m where the guide and diver were and then at 55 minutes we ascended and did the safety stop. You will see when diving some divers ask for nitrox and some do not. So you can see groups only on 21% or you might see a group with one diver on 32% and others on 21% but they all stay at the same depth more or less.

So for me I enjoy being able to do dives where the guides are there more for the other divers than for me lol Sometimes back on the boat divers would ask the guides why they don't ask me to check my gas too often. They just reply that fat dude is just better than any of the guides on air lol. I always let them known when I have one hundred bar but many times I was back on the boat with more than 100 bar.

The Savedra manager Koz I have known before she became an instructor and is now an IDC Course director. So when you have someone you have known for 8 years and done many dives together it's great. But I still follow the guides dive briefings and the 60 minute dive time.

Trip Report Thread 'Moalboal: Savedra Dive Centre'

Mar 29, 2024

Recently did a 3 day trip to Moalboal, which is famous for the Sardine ball just off the beach.

Accommodation: We stayed at the Dreamcatcher Hostel, which is in Panagsama approx 300m from the beach. We picked this place on arrival as it’s up a small lane and therefore escapes all the traffic noise. The rooms are comfy enough with fan and a/c. There is a nice area out front with hammocks and chairs to chill. Staff were really nice.

Diving: We initially went into ‘Amigos Dive Centre’ but the music was just too loud for us in there. Asking questions at the reception desk and had to strain...

• carono6333
• Replies: 12
• Forum: Philippine Paradise Divers

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[Blackcrusader]

That seems like good practice by Savedra.

Yeah they have great staff there. They do have some freelance DM's as well as they can get pretty busy.
So some divers will be doing shore dives, some on one of the three dive boats they use going to different sites. Pescoder island they do the second dive every day as it is the most popular dive site. Visibility can be hit and miss but when vis is not so great I might look for macro stuff to take video or photos of.

One piece of advice. Learn the functions and settings of your dive computer. If it has audio alarms then learn what they sound like. My Shearwater Perdix does not have Audio alarms. Yet on dives I hear alarms going off and the diver with the alarm going off is pointing at my dive computer clueless to their own alarms. My settings are such that my dive computer does not give you a safety stop. You have to manage that by yourself. Also when ascending from the safety stop ascend slowly. Many people just rush to the surface after a safety stop risking a lung injury

 

[Centrals]

There is no difference in diving between air and Nitrox. Depth is the limiting factor. BTW, air is Nitrox 21.
Any responsible operator would not mix air and nitrox divers together. If they do then they should provide TWO guides to take care of the respective group.
In Moalboal, Nelson's diver shop is the place.