Light back gas deco

[Julius SCHMIDT]

I have to carry a pony for solo every dive and there's 50% in that so is there a place for me somewhere

 

[rjack321]

If we followed that logic we’d all leave ScubaBoard. It has never ‘all been said.’

In the same week? Normally these topics take a few months break then resurface. Perhaps one day of pause per page of thread is reasonable. The other 17 page thread about backgas deco means we have to take a 17 day break before we go all over it again.

 

[Jwoobs]

I have to carry a pony for solo every dive and there's 50% in that so is there a place for me somewhere

Are you limited to 18m while solo diving?
I.e. ppO2 1.4bar? Otherwise could have ox-tox concerns if you have to deploy your pony at depth.

 

[Blackcrusader]

Hi folks, Do you recreational divers ever do light back gas deco?

Thanks for the poll. I think there are two areas for this. Those that are planned dives and those where the diver goes into deco unplanned. I wrote about being on a dive with a visiting instructor on her vacation who wanted to get some photo's deeper than 32m of a pigmy seahorse and went 10 mins into deco because by the time we got to the site NDL was getting pretty limited. I was in two minds stay in NDL and ascend above her or stay with my assigned dive buddy. I chose the latter. We were on single tanks. We ended up with a shorter over all dive time as we went and did our deco clearance and surfaced before the rest of the dive group finished their dive. It was her last dive of her vacation and she wasn't leaving without those photos.

 

[Diving Dubai]

Are you limited to 18m while solo diving?
I.e. ppO2 1.4bar? Otherwise could have ox-tox concerns if you have to deploy your pony at depth.

Ox Tox isn’t instant.

AT 40m it’d only be a 2 min ascent up to 18m, so no biggy in an emergency- depends on the whole dive plan

 

[AdivingBel]

I don't do planned deco for rec dives. I may on rare occasions exceed NDLs by a few minutes if there is something to see and I have sufficient gas. In those instances I usually clear deco before I even reach my stop depth or very shortly afterward. I don't recommend this practice for new divers, but for those with the situational awareness and judgement that comes with experience I don't see this as "risky" behavior. All IMHO, YMMV.

 

[Diving Dubai]

The only hard line on the dives we organise, is the 60 min dive time (no ifs no buts)

Given the nature of our diving we always have s significant gas contingency. By that I mean, if I've staying above 30m I'll generally be surfacing with 100bar/1500L or 50Cu ft of usable gas remaining. Thus we have the option based on the fluid nature of the sites. Maybe we need to go deep to find vis below the eplankton layer, maybe we'll bump into a mola mola or something else worth hanging about for deep.

At that point it's an educated decision based on the computers ND, current conditions and a simple mental exercise of gas/time calculation, while honouring the max dive time min pressure restrictions. We all know how our computers deal with Deco, so none of it is a surprise.

Since most of us are riding scooters we're all carrying redundant bail outs (ponies) which are sized to and carry a mix (40-50%) to allow for accelerated deco if required (or just a richer mix flush when shallow). All based on experience knowledge and training not a finger in the wind guess

 

[Celt]

For me decompression is part and parcel of scuba and should always be planned for. All my dives are planned. And for the people on this tread who are doing deco, ye are not recreational divers and should get a grip and start planning deco as 10 minutes could very quickly become 30 minutes. The deco is the most important part of any dive and should be taken seriously.

 

[Angelo Farina]

Does "recreational divers" mean people without any formal tech/deco training?

On this side of the pond (Europe) many divers are formally trained to recreational deco during the first-level course (OW). Or perhaps at the second level (AOW), if they start with a very basic first course.
I mean courses organized by no-profit clubs, not by commercial entities, and employing didactics such as CMAS, BSAC, FIPSAS, FIAS, etc..
That's fully recreational deco dives, nothing "tech". My certification (CMAS-FIPSAS) is for recreational diving down to 50 meters, in plain air, with deco and with a buddy.
I am not a tech diver, nor I own a tech computer allowing to be set up for mixture changes during the dive, etc..
I have a very basic Cressi Leonardo, which is just fine for these dives "just beyond NDL" in air...

Said that, the poll seems clear to me, and makes no mention to the certifications owned.
It simply asks if YOU ever make dives with some amount of deco, done using the back gas (aka main tank), instead of an additional tank.

 

[Compressor]

On this side of the pond (Europe) many divers are formally trained to recreational deco during the first-level course (OW). Or perhaps at the second level (AOW), if they start with a very basic first course.

Good to know.
On the west side of the pond you talked about, they say it's taboo which I think is not right. All dives are decompression dives physiologically as you know. The only difference is if there is a physiologic barrier (mandatory stop) to the surface.