o2 clean

[Thrillissues]

I have recently finished my Advanced nitrox, and decompression procedures classes. I have been looking at regs to put on stage bottles and on an o2 bottle. I have two dacor vipers and was wundering if they would be suitable to use for deco regs. I would just flat out buy some new regs but i have already purcahsed two mk25's and a set of doubles. And being a Marine Corporal that means i am now broke!

 

[Deal Me In]

hey thrillissues, got some bad news for you. i've just finished the same class and had the same regulator. it can't be done according to the people at dacor. there is something called a poppit (sic) that can't be replaced to make the reg suitable. as for being a marine, in case you haven't heard it in awhile.....thank you.

mc

 

[theskull]

The manufacturers mostly agree now that any regulator can be used with up to 50% EANx without any customization without any problems. Those in the cave diving community mostly will use any regulator off the shelf even with O2; parts may wear out a little faster, but have not heard of any other consequences. You do assume all liability since the manufacturers will not recommend this practice--they sell a few regs that are "designed" for O2.

theskull

 

[LUBOLD8431]

That number should be 40% percent o2.

 

[mketa]

I have recently finished my Advanced nitrox, and decompression procedures classes. I have been looking at regs to put on stage bottles and on an o2 bottle. I have two dacor vipers and was wundering if they would be suitable to use for deco regs. I would just flat out buy some new regs but i have already purcahsed two mk25's and a set of doubles. And being a Marine Corporal that means i am now broke!

Corporal, you are on the right track in trying to use what you have so make the swap, use the dacors for your back gas and the mk25's for your deco regs. Why? First, the Dacors are diaphram regs. If you have a problem underwater with them on your deco tanks and have to do an underwater switch, there is a possibility when you recharge the regulator underwater with water in it, the diaphram can blow out and the reg is completely worthless. Thus, it is not a good practice to use diaphram regulators as stage regs or deco regs. On the other hand, you have scubapro mk25's which are piston regs and work wonderfully as stage regs and/or deco regs. Again if you have an underwater problem where you need to switch regs, you can charge a piston regulator underwater with water in it and it will work, every time.

As far as o2 cleaning, scubapro makes a nitrox kit for the mk20 and I think the 25. These are the only reg scubapro makes that as far as I know has an nitrox kit available. However, by mfg specs, this is only good to 40% which is BS. I have been using all Scubapro regulators mk10, 10+, 15, 20's and use the standard parts, clean them with white vinegar and ultrasound and then soak in Blue Gold, reassemble in a clean environment and feel very comfortable using any reg I own on 100%.

I have had one microexplosion inside a tank that did not have "O2" compatible parts but that was only because a micro fragrament of SS broke loose inside the fill system and when it hit the HP seat of the Thermo Valve, it exploded, that sounds worse than reality. Reality, the teflon seat simply vaporized, this being the fuel for the explosion and when vaporized, there was no more fuel and thus no explosion or fire or anything of that nature. I mention this as charging a first stage on 100% goes through a sintered filter and thus nothing is going to fire down the HP oriface and cause an explosion. If you are clean, keep covers on your din fittings, clean the regs every year and do the annual maint. You are ready with what you have but do not use diaphram regs for deco or stages, just one failure point you do not need to have.

My last bit of advice is to go on EBAY and find a couple Mk10G250 regs for your deco/stage regs as they are the best and easiest to work on and IMHO the most reliable reg every made. You can find them for about $125 - $150 with din but do not pay much more.

Hope this helps. If you need further assistance please email me off line.

Martin

 

[DA Aquamaster]

All of Scubapros regs sold since October 2000 are approved for use with Nitrox up to 40% at 3300 psi except for their titanium first stages. Consequently, SP does not sell a dedicated nitrox reg since they are all Nitrox approved.

Per Scubapro's service bulletin, the chrome plated brass Mk 20/25 is the only first stage that is SP approved for use with mixes over 40% and it is approved for up to 100% O2 at 3500 psi with installation of the Nitrox kit and proper 02 cleaning.

In practice, the MK 2 Plus can be used with 100% O2 as long as it is O2 cleaned and has the current production EDPM o-rings. Due to it's design, there are no high pressure areas in the reg downstream from the HP seat, so O2 at high pressure is not really an issue in the first stage. There are also only 2 dynamic o-rings in the reg and both are exposed to no more than the maximum intermediate pressure of approx 145 psi.

The MK 2 makes an excellent reg for a deco bottle as it is small in size, very simple in design, very durable and, as mentioned above, will survive being changed under water.

One caution though, if you do happen to do this the reg will need to be serviced as soon as possible as you need to clean any salt water or salt deposits out of the reg. If you change a MK 2 underwater you WILL end up with a couple drops of salt water in the compression chamber where it cannot be rinsed out or removed without disassembling the first stage.

The Mk 10 also makes a great reg for back gas or for deco bottles. It is more compact than a Mk 20/25 and with proper cleaning and current O-rings tolerates the hotter mixes used for deco. In year past I used third party O2 compatible Viton o-ring kits for the Mk 10 and Mk 15. But SP currently uses EDPM o-rings that are well suited for O2 use. I am not sure why they don't just come out and approve the older regs for O2 use with proper preparation, but at present it is not SP approved.

I would also agree that the G250 is a great second stage and normally a great buy on e-bay. Of course the all metal Balanced Adjustable is usually an even better buy and can be upgraded to use the same internal parts as the G250 and offers nearly identical performance in a slightly smaller and more durable metal case. The upgrade for an Adjustabel or older Balanced Adjustable requires the poppet and balance chamber that already come in the G250 annual service kit and a new spring that costs an additional $1.00. In some cases a new lever may be required but this only a $3.00-$4.00 item.

 

[Norm]

Corporal I have to basically agree with theskull. Alot of what we see and most of what we hear is hype. Having said that, In my opinon: I have used 10 year old, uncleaned regs with 50/50 with no problems whatsoever. I have seen pure oxygen put into 8 year old empty aluminum 80 that has never been oxygen cleaned and SLOWLY filled to 1200 PSI! (I am telling you this only to show you alot of talk is hype. I DO NOT advocate any of this to anyone in any way!)
To continue, In my opinion: I DO believe in oxygen cleaning for 100%, but even that primarily only applies to the first stage (HP). I use Dawn soaks, lots of rinses, a wash with isopropyl, then a couple more risnes. (Worked fine for me with 100% for years!) I do use Viton parts for pure oxygen when available. One of the biggest safety factors when working with oxygen is GO SLOW! This applies when opening valves, filling, mixing, etc. Take it slow and easy!
A friend once bought a brand new "Oxygen-Clean" regulator. For some reason he didn't feel safe with it so he asked me to go through it before he committed it to 100%. I brought it home, tore it down, and guess what? Right there, inside the first stage, was a huge drop of cutting oil from the factory, left over from the maching process! "Oxygen Clean" ? Yeah, right........ I cleaned it up for him, lubed it with Halocaron grease or Crystolube, (don't remember which), checked the I.P. and gave it back to him ready to go.
Good common sense is the best rule. Just treat oxygen like gasoline. While it is not a fuel it is an accelerant. It has to have fuel and heat. The heat can be something as simple as opening a tank valve too fast and the fuel could be a single drop of cutting oil. A tiny piece of metal can be both.
Some folks claim that Teflon isn't oxgyen compatible but I've never had/seen any problems from using it. I do keep my oxygen rigs committed to pure oxygen use. They are my "sacrificial" regulators. Vince Harlow's book is a big help to alot of folks on this subject. Just my opinions......
Norm

 

[AdamHorsman]

O2 cleaning standards:

Navy any mix >25% O2
Nasa any mix >25% 02
OSHA considers any mix >23.5% "Oxygen Enriched Air"
IANTD any mix >40%

The scuba industry states a 40% cut-off point. I know damn well who I want backing me if I am in court.


Adam

 

[LUBOLD8431]

Actually, its the regulator manufacturers that set the 40% limit. So, if something happens, and you have a problem, sue them...

 

[AdamHorsman]

[

Actually, its the regulator manufacturers that set the 40% limit. So, if something happens, and you have a problem, sue them...

I understand that, but I'd like to see the justification on the decreased standards for the magical "40%"; and then if Joe Blow, the average dive shop owner, doesn't O2 clean a reg for 36% use, based upon the manufacturers recommendations, and god forbid the 1st stage or valve goes out, it very well could be brought back to you.

If a lawsuit were to arise any good lawyer is going to get the Navy standards, or NASA standards, or ANDI standards, or OSHA standards, out and use them against both the manufacturer, and most likely the person who has been performing the service. Thank you no.

Adam