Deco Reg

[DIR-Atlanta]

Soggy, please share your reasoning on the Poseidons...

I'll jump in on this. Right off the top of my head:

• Upstream design
• Non-standard hoses and fittings
• Non-standard purge mechanism
• Not field serviceable without tools

There are probably a few more that could be added to that list, but those are the major "negatives".

 

[dab]

If your looking for factory cleaned 02 regs, there are several out there. Poseidon, aqua lung, and oms come to mind. Diverite may also offer one if my memory serves me right.

 

[dab]

Oh, and I've been diving Poseidon reg's for several years. When your looking at deep and cold, they've proven themselves over and over. My experience, my comfort level....

 

[Scared Silly]

Because you are already diving Atomic Regs I would find a Z1 and O2 clean it. This would address the service issues. This past spring my local shop was selling off their rental Z1s. I considering doing this because we have a bunch of other Atomic regs but decided for $$ purposes just to O2 clean my MR12 regs.

 

[DIR-Atlanta]

Worrying about buying O2 clean from the factory shouldn't even be a consideration...that's basically a 1 year 'solution'...your reg still has to be cleaned and serviced at some point, probably when you first get it and every yearish thereafter.

The other issue here is to get away from the mindset of "deco regs", "stage regs", etc. Basically you have back gas regs and then you have stage regs (which are also used for deco bottles). Stage regs are stage regs, and need to be "plug compatible" with each other. Otherwise you are inviting the potential for confusion or a mistake (Robbie McGuire, Thunder Hole, 1995).

I'll not debate the issue of O2 cleaning vs not, but if you feel that it is important for a particular reg in your "fleet" to be O2 clean, then they all must be O2 clean. From a procedural standpoint, it's not really a good idea to have one "special function" reg. Clean them all or don't clean any of them, just make sure they can be used interchangeably.

 

[Soggy]

I'll not debate the issue of O2 cleaning vs not, but if you feel that it is important for a particular reg in your "fleet" to be O2 clean, then they all must be O2 clean.

I concur wholeheartedly.

 

[Scared Silly]

up to 100% 02 AL40 dedicated "full time" to deco mix.

A side question I was taught that it is better to use a LP cylinder for pure O2. If this is the case using an Al40 as a LP bottle would make it an 30. Or are folks using AL bottles to their full pressure rating for O2.

Also would it also do not be perfable to have a dedicated pure O2 bottle and marked as such and have another bottle for other deco mixes? Which is also how I learned.

I have an AL40 for deco and was looking at a LP20 for an O2 bottle. Which for the dives I do they fit the bill. Curious to know what others use, size wise for a dedicated O2 bottle.

 

[Soggy]

For ocean diving, the tank of choice is Al40s. Cave diving allows for a few other options since you don't carry gasses beyond their MOD, but Al40s and Al80s are preferable. Generally speaking, steel tanks should not be used if at all possible due to their poor buoyancy characteristics as slung bottles.

O2, like *all* slung bottles should be permanently marked with MOD. 100% is additionally marked with "OXYGEN 20".

 

[DIR-Atlanta]

Oh, and I've been diving Poseidon reg's for several years. When your looking at deep and cold, they've proven themselves over and over.

With all due respect, dab, the "deep and cold" argument doesn't really hold up anymore. It's true that in years past, the Poseidons were the favorite regs for those conditions, but nowadays, almost any decent quality environmentally sealed reg will perform just as well, when used with the proper breathing gas. There are literally hundreds of cold water DIR divers all over the world who prove that point on an almost daily basis.

The "deep and cold" attitude tends to be a holdover from the "deep air" days, when regs had to be able to flow well to deliver air at the higher densities created by deeper profiles. Current thinking (at least in DIR circles) is that we use helium-based mixtures to mitigate those problems. Helium reduces the breathing gas density, which reduces the need for high flow second stages, which in turn reduces problems associated with freeflows and freezing.

I'm glad that you have had such great success with your Poseidons. Many divers use them still and are quite comfortable with their idiosyncracies. From a DIR standpoint however, they introduce too many potential problems (noted in my posting above), which is why we do not use them.

 

[dab]

With all due respect, dab, the "deep and cold" argument doesn't really hold up anymore. It's true that in years past, the Poseidons were the favorite regs for those conditions, but nowadays, almost any decent quality environmentally sealed reg will perform just as well, when used with the proper breathing gas. There are literally hundreds of cold water DIR divers all over the world who prove that point on an almost daily basis.

The "deep and cold" attitude tends to be a holdover from the "deep air" days, when regs had to be able to flow well to deliver air at the higher densities created by deeper profiles. Current thinking (at least in DIR circles) is that we use helium-based mixtures to mitigate those problems. Helium reduces the breathing gas density, which reduces the need for high flow second stages, which in turn reduces problems associated with freeflows and freezing.

I'm glad that you have had such great success with your Poseidons. Many divers use them still and are quite comfortable with their idiosyncracies. From a DIR standpoint however, they introduce too many potential problems (noted in my posting above), which is why we do not use them.

The theory sounds good.........now if I can figure out a way to explain that at 200ft to the diver who's reg is free-flowing....