Deco bottle

[PerroneFord]

Data,

I don't know the instructor, but I am very wary of anyone who whould call EAN80/80%, 80/20.

 

[bwh6]

Data,

I don't know the instructor, but I am very wary of anyone who whould call EAN80/80%, 80/20.

How many people do you know who call 50% 50/50?

 

[PerroneFord]

None.

 

[Sideband]

Here's a problem. Get a bottle of 80/20 and a bottle of EAN80 and throw an O2 analyser on them both. There is a bit of difference in use though.

Joe

 

[PerroneFord]

There is a bit of difference in use though.

Joe

And price!

 

[Jasonmh]

My personal experience has been that I felt much better after diving when I started doing deep safety stops on deeper dives and slowing my ascent rate down to a crawl after the shallow safety stop. It went from feeling worn out after a couple of dives to feeling fresh as I had that morning.

Definitely. I had experienced some of this before, but not as dramatically as I did this past weekend. We did a longer than usual dive (>60 mins) and after the last 10 foot stop I spent several minutes getting from 10 to 0 because there happened to be some fish there to look at. When I got out I felt as good as I had before the start of the diving that morning. A very noticable difference!

 

[SmileMon]

Actually I've heard it many times (the 50/50 or 80/20 but also heard a lot Nitrox 50, or 80 percent), people are not very careful in saying exactly what they mean, the only time I'm sure what I got is if I asked for it myself AND analyzed it myself (some people will say the only time they are sure is if they mixed it themselves, but I'm not there yet).

I think people are just not careful enough with how they speak about these things or they count only the oxygen because of MOD reasons (for decompression anyway).

Anyone has a serious book written by serious people about all the deco theories and mixes? can you tell me its name?

Thanks.

 

[PerroneFord]

There are plenty of them out there. But what "people" are you talking about when you say people aren't careful. All the people I dive with or hang around are VERY serious when it comes to how they talk about gases. Maybe after watching a few friends die, you get careful.

And your oxygen analyzer isn't gonna tell you a 50/50 mix from a 50% mix. But a few pulls on the regulator wil!

I found this book helpful:
http://www.amazon.com/gp/product/1904381200/ref=sr_11_1/102-9836456-1770532?ie=UTF8

You can read some of this:
http://www.decompression.org/baker/home.htm

There are many others.

 

[MSilvia]

Out of curiosity, why 80/20 instead of Oxygen?

So his buddies can laugh at the way he squeaks like a chipmunk when he gets back on the boat.

 

[bwh6]

Actually I've heard it many times (the 50/50 or 80/20 but also heard a lot Nitrox 50, or 80 percent), people are not very careful in saying exactly what they mean, the only time I'm sure what I got is if I asked for it myself AND analyzed it myself (some people will say the only time they are sure is if they mixed it themselves, but I'm not there yet).

I think people are just not careful enough with how they speak about these things or they count only the oxygen because of MOD reasons (for decompression anyway).

Anyone has a serious book written by serious people about all the deco theories and mixes? can you tell me its name?

Thanks.

I would guess that 50/50 and 80/20 are terms for nitrox dating from before the wider use/knowledge of trimix and the F02/FHe naming convention. Searching this board will find numerous threads with these terms.

Also, from 1997: http://www.baue.org/library/bakers8020.html

I would stick with the F02/FHe convention and encourage your instructor to do so too. But many people DO still talk of 80/20 and 50/50 and it helps to not get confused. There IS a big difference between, say, 50% and 50/50 heliox for decompression; try comparing schedules using your favorite algorithm.

Brian