Diving on nitrox and air with the same regs?

[crpntr133]

OK what do you say to a O2 clean 1st stage? Switch or no switch?

 

[Web Monkey]

OK what do you say to a O2 clean 1st stage? Switch or no switch?

The only time you would need to O2 clean the first stage is if you were using very high concentrations of O2.

For normal recreation mixes of < 40% O2, you don't need to do anything to the first or second stage.

However if the manufacturer specifically states that the regulator is not to be used on anything with a higher O2 content than air, you'll probably want to check into it and find out why.

Terry

 

[Scuba Ken]

The general Guideline is that anything that can be subject to higher than 40 percent oxygen needs to be oxygen serviced and treated as if it was 100 percent ox. Less than 40 percent can be treated as standard air according to the DSAT gas blender manual. In Rec diving the only thing that might be exposed to higher than 40 is the tank during partial pressure filling. Having your tank O2 clean and stamped is very important or you will likely have hard time getting nitrox fills. A partial pressure blending facility may even want the tank serviced by them prior to filling, do to the dangers. Some people are just so distrusting of others when itcomes to blowing themselves up

 

[crpntr133]

The only time you would need to O2 clean the first stage is if you were using very high concentrations of O2.

For normal recreation mixes of < 40% O2, you don't need to do anything to the first or second stage.

However if the manufacturer specifically states that the regulator is not to be used on anything with a higher O2 content than air, you'll probably want to check into it and find out why.

Terry

I guess I should have been more specific. If the first stage is O2 clean for use in >40% should you not use it for air. Lets take it one step further and say that the air isn't hyperfiltered or such. Just plain ole dive air.

 

[JeffG]

I guess I should have been more specific. If the first stage is O2 clean for use in >40% should you not use it for air. Lets take it one step further and say that the air isn't hyperfiltered or such. Just plain ole dive air.

gee...do you store your regs in an O2 clean room?



This thread is too funny.

I guess I am close to death due to the fact I couldn't care less which reg I have goes on which tank.

<snicker>

 

[Web Monkey]

I guess I should have been more specific. If the first stage is O2 clean for use in >40% should you not use it for air. Lets take it one step further and say that the air isn't hyperfiltered or such. Just plain ole dive air.

As long as you're using Nitrox @ less than 40%, there's no reason to O2 clean either stage of your regulator and it's irrelevant whether or not you get hyperfiltered or regular air.

Terry

 

[Charlie99]

I sure wish I could get Mythbusters to try to make this happen. The odds of this seem astronomical to me.

1) The fill has to be fast enough to generate enough heat to flash the oil.

2) The oil and EAN have to be right there together.

3) Neither of them can be underwater (Some places still dunk the entire rig underwater while filling).

I get that there's the "potential" here, but it sure seems remote.

I do recall an incident a few years ago. IIRC, it was in California and the reg was on a very rich deco bottle -- something like 80% or 100%. Unfortunately, this is just from memory because I don't have a link to info about the incident.

<found it! http://groups.google.com/group/rec.scuba/msg/28bf9b3543994200?hl=en or see the fourth post below>


I dive much more conservative than a 60fpm direct ascent to the surface after doing USN NDLs. I'm conservative in this area too and minimize this sort of risk by simply using an Atomics B1 with brass innards in the first stage (titanium 2nd stage, but that only sees IP of 140psi). The M1 which uses monel for the 1st stage which is corrosion resistant without being flammable. They are a pound or two heavier than the Atomics titanium regs, but that not a very big penalty.

Charlie Allen

p.s. The problem is NOT a fast fill of the tank. The problem is the rapid pressurization within the reg when you turn on the tank valve. Obviously cracking open the valve slowly would less the heat generated by rapid compression of the gas already in the first stage.

 

[ucfdiver]

How often do you guys actually o2 clean? I mean my tanks are "o2 clean" but they get exposed to regular air every second that they aren't underwater.

 

[Charlie99]

How often do you guys actually o2 clean? I mean my tanks are "o2 clean" but they get exposed to regular air every second that they aren't underwater.

You remove the valve and open up the tanks between dives ???

 

[crpntr133]

gee...do you store your regs in an O2 clean room?



This thread is too funny.

I guess I am close to death due to the fact I couldn't care less which reg I have goes on which tank.

<snicker>

I ask this because there seems to be the idea that once it is O2 clean for 100% that you can't use it for regular air. This is something that I don't buy. I agree with you that you store it the best you can but it isn't going to be 100% clean.

Diving 40% I could care less what reg it is as long as it works.