Feedback on recent two-tank and dive limits

[inquis]

Recreational NDL diving - anywhere between 100/100 to 70/70
Planned decompression diving - below 70/70, for example, 45/90, 40/85, 35/75

You're drawing a distinction when using GFLow values (the first of the pair), but that is irrelevant for NDL diving. Additionally, for deco -- when both are relevant -- you say "below" and then give a GFHigh that is above your limit. It's no wonder people can't understand you.

 

[Mobulai]

Wouldn’t it be easier if we stop discussing GFLo and deco conservatism in basic scuba — it’s already a (slightly) confusing topic for (some) tech divers; let’s not overconfuse rec divers
Otherwise we’ll also start talking deep stops, HPNS, hydrogen dives and bailouts planning

 

[34109411]

i have such a headache after reading all this. Iam close to 300 dives and used the following computer mares m1, suunto zoop, mares quad air, sherwater peregrine TX.

That's should not be rocket science to go dive with them. I don't play much with the factory setting and never encountered a problem whatsoever.


Let's just go diving.

Be safe

 

[grantmac]

Wouldn’t it be easier if we stop discussing GFLo and deco conservatism in basic scuba — it’s already a (slightly) confusing topic for (some) tech divers; let’s not overconfuse rec divers
Otherwise we’ll also start talking deep stops, HPNS, hydrogen dives and bailouts planning

GFs are simple, if someone is struggling with them they shouldn't be considering tech diving.

 

[Mobulai]

GFs are simple, if someone is struggling with them they shouldn't be considering tech diving.

Yes, I meant their implications is where it starts to get a bit complex
And I agree, they shouldn’t

 

[old frogman]

Apologies for the headache. But GFs can be a headache for the recreational diver. I agree that if you are using a GF on your computer for NDL dives you need to monitor the duration of your bottom time. When you select a particular GF, it will reduce your bottom time not only on your first dive but even further on your second dive and even further on your third dive (common on dive resorts and liveaboards). If not monitoring your computer (on the subsequent dives), your computer may direct you to complete a multi-stop ascent with the first stop at 21 metres. This surprise may be very challenging for an inexperienced recreational diver.

In reality you may not need to do the multi-stop ascent. However, you selected the GF and now you have to decide to either follow the computer on a long multi-stop ascent or just do a 5 min safety stop at 5 metres. What would you do?

 

[rongoodman]

I routinely do five dives daily on liveaboards with my Teric set to the default 40/85 and have never seen anything remotely like that. The most deco I've ever incurred was a couple of minutes on deeper dives out at Cocos Island, such as Dirty Rock, which cleared on the way up to the safety stop.

 

[boulderjohn]

If not monitoring your computer (on the subsequent dives), your computer may direct you to complete a multi-stop ascent with the first stop at 21 metres. This surprise may be very challenging for an inexperienced recreational diver.

So you are warning people that if they use GFs, they need to watch their computers to make sure they don't go into decompression. Are you saying that if they use another system, they don't need to watch their computers to make sure they don't go into decompression? What's the difference between Buhlmann with GFs and any other system?

If you are surprised to find you have an unexpected decompression stop at 21 meters, you made a super serious NDL violation to get a first deco stop that deep, even with the lowest of the preset GF low settings. I would be surprised if an NDL diver with an AL tank could make that happen.

 

[Blackcrusader]

Nonetheless I think most recreational divers will be perfectly fine by leaving their computer at the default settings and knowing enough to follow what it says, which is what happened here...

They may as well not use a dive computer then. The issue really is that people buy a dive computer slap it on their wrist and have no understanding of its functions. We recently had another thread where a diver was telling us his Shearwater was wrong as it had shown he went into deco. He also had no clue about his dive computer. The problem is people don't even know what default settings their DC is using as they never checked it in the first place. Then these divers are all surprised when things didn't go as expected.

 

[Blackcrusader]

I routinely dive five dives daily on liveaboards with my Teric set to the default 45/85 and have never seen anything like that. The most deco I have ever incurred was a couple of minutes on deeper dives out at Cocos Island, such as Dirty Rock, which cleared on the way up to the safety stop.

I use GF 45/95 and on several dives in Maldives this year where 10 minutes of deco was done also cleared deco obligation on the dive before safety stops. My dive buddy and I use the same GF profile.