nitrox 50/80 deco tables

[Digger]

I might be wrong but I'm sure you can go from BSAC advanced to TDI/IANTD deco procedures, so you get a 100% ticket as well as the ability to do deco and all the training/skills/advice.

The BSAC course is barely enough to be doing stops on 50%, I had to intervene a couple of times on mine when theory was just plain wrong. Unfortunately there are some really good BSAC instructors out there but some very inexperienced ones who seem to hardly be diving nitrox at all and teaching the courses. Others mileage will vary, but if you want to do tech diving get a tech instrcutor IMO.

Digs.

[chrisch]

Originally Posted by romperstomper1

I did not relise when I started that the bsac advanced nitrox course did not cover accelerated deco (in which case its hardly advanced also I don't see the point in using a 50 mix for deco in such a case) anyway I've learnt a lot at a bargain price and will have to try and find the next course !
Thanks for reply's

Glad to hear you are looking at getting some more training. FYI the IANTD charts covering air with EAN50 deco can be found if you look around. For example here: http://www.diveriteexpress.com/logow...vetables.shtml

You will find these types of tables very different to the 88s and their proper use would be covered in a decent training course, together with things like EAD to use standard table (again outside the scope of the BSAC course). Nonetheless I'm sure you could figure out what sort of time you can gain using this methodology and that might be useful in deciding when/whether to get more training.

Use with care.

Dive safe.

Chris

[Narked@50]

I have to largely agree with Diggers first post here - and also his later ones.

It does seem, without trying to offend you, you have not understood what the course was actualy about regarding content, and have obviously quite a bit to get to grips with. Saying that, it's good you are asking for advice, but it will only do you any good if you take it. It's all too easy to think you know better and everyone else is just wet, but get the right training in the first place and you could save yourself a lot of hartache. Any Hayhurst in the North and Mark Powel in the South would be my recomendations.

Dive safe

James

[Ferg3333]

Originally Posted by romperstomper1

I did not relise when I started that the bsac advanced nitrox course did not cover accelerated deco (in which case its hardly advanced also I don't see the point in using a 50 mix for deco in such a case) anyway I've learnt a lot at a bargain price and will have to try and find the next course !
Thanks for reply's

Thats the not the point behind the course now is it. Just consider IANTD Advanced Nitrox max depth after qualification is 42m and limited amounts of deco using 50% upto a maximum of fifteen minutes decompression. If you are desparate for tables buy the iantd technical diving encylopedia it has them all, buy a laminator and go ahead, but the statistics are against you.

A 50% mix is more than adequate for decompression as it has a whole 29% less nitrogen in it!!!!!!! Plus most people cannot get high pressure o2 fills when partial pressure blending, depending on several factors cylinder size, how much of your 02 you've already used etc etc.

Also consider TDI ( I may be wrong ) but there advanced nitrox covers you to use upto 100% but you need to do decompression proceedures before you are qualified to use the gases for extended deco! So you see its swings and roundabouts in the end. there are plenty of instructors on here would help you go down the technical route but take it slow, the uk waters are unforgiving! Plus anything deeper requires a twinset and in my opinion a minimum of an ali 7 although some do like ali 40s.

My advice do another course IANTD, TDI or BSAC ERD since you need the card to buy the gas!

Just my 2p

Dive Safe

[wreckweasel]

Personally, for single stage diving, my mix of choice is 50%. Anyone turning their nose up at this would do well to study some deco theory and think of real world applications (fill logistics/Gas Gradients/distances to next mix in a fuck up).

If its deco you want, you'll need TDI Adv Nx + Deco Procs, or IANTD Adv Nx, or GUE Tech 1. If you're following the course route that is. (Can't comment on PSA, I dont teach them or know about their course structure).

I'd suggest a lot more reading is in order, whether you do a course or not.

Theres some info at our site, but I know mark powell has a useful resource area too.


/Zak

[garethwebber]

Originally Posted by Digger

The BSAC course is barely enough to be doing stops on 50%, I had to intervene a couple of times on mine when theory was just plain wrong.

Digs.

Having done the BSAC course recently, I am intrigued by your assertion that parts are wrong. Which bits?

Gareth

[Garf]

before taking the DIR path, I used 50% as a stage mix wherever possible as wlel. It gives a nice gradient over the weak nitrox mixes, but its much more forgiving than the richer mixes. finally, you can get onto it at a nice depth without having to bolt for the shallows if something goes wrong.

It's just a nice mix that works.

[Paul Oliver]

Originally Posted by Garf

I used 50% as a stage mix wherever possible as wlel. It gives a nice gradient over the weak nitrox mixes, but its much more forgiving than the richer mixes. finally, you can get onto it at a nice depth without having to bolt for the shallows if something goes wrong.

It's just a nice mix that works.

50% is my preferred standard deco mix and it works very well for me.

I accelerate my deco but tend to then cancel that out with a very slow assent and an extra 3 min at 3m anyway.

[Garf]

Originally Posted by Paul Oliver

50% is my preferred standard deco mix and it works very well for me.

I accelerate my deco but tend to then cancel that out with a very slow assent and an extra 3 min at 3m anyway.

I do something similar. I accelerate the deco, but then do a ludicrously slow ascent from 6M. water and weather conditions permitting I do a one minute stop at 5m, one minute at 4M, one minute at 3M, one minute at 2M, one minute at 1M before hitting the surface.

This makes a tremendous difference to how I feel when I get out of the water so try to do it every time I do into deco.

[JKS]

Originally Posted by Garf

I do something similar. I accelerate the deco, but then do a ludicrously slow ascent from 6M. water and weather conditions permitting I do a one minute stop at 5m, one minute at 4M, one minute at 3M, one minute at 2M, one minute at 1M before hitting the surface.

This makes a tremendous difference to how I feel when I get out of the water so try to do it every time I do into deco.

I do this too. I try to ascend as slow as absolutely possible through the last 3m. It really does make a difference to how I feel when getting out of the water.