switching gases

[markrovner]

OK, this may be a dumb question, but...

I just got Nitrox certified and did a trip where I used EAN32. I happened to be flipping through the owner's manual for the reg recently, and it says never to go back and forth between air and Nitrox, the risk being from residue left by less-than-stellar filtration of the air fills.

As a practical matter, do people really do this? I know I'll be in places that have no Nitrox from time to time -- do I really need a second reg?

m

 

[spectrum]

As long as you stay below 40% oxygen it should be a non issue for the regulator set.

I can see that as a cylinder precaution for PP blending where a tainted cylinder could react with the intoduction of pure oxygen. Hence the need for 02 clean cylinders.

Pete

 

[The Horn]

I would think it more in line with keeping a tank that is certified for nitrox solely for that purpose to protect the person filling if they do a partial fill with O2 and then top off with air to get you a 32% mix. The big concern is the pure O2 so your 32% mix will not be reactive with anything in your regulator from another air source. Normal recomendation is to have dedicated equipment for mixes above 40% I do believe

 

[Mako Mark]

your reg is not going to explode, they put that in there (as stated) for high O2 mixes and for liability reasons.

What are you reading the instruction manual for anyway??? Real men are not supposed to read the instructions, ask for directions or put the tiolet seat down... Get with the program..

 

[markrovner]

your reg is not going to explode, they put that in there (as stated) for high O2 mixes and for liability reasons.

What are you reading the instruction manual for anyway??? Real men are not supposed to read the instructions, ask for directions or put the tiolet seat down... Get with the program..

This is a good question and it is totally potty-related. It was the only thing in the loo to read. If it makes you respect me more, I've logged most of my dives on the reg and just peeked at the manual last week...

 

[DA Aquamaster]

Most shops that sell both air and nitrox use air that meets the same standards as the air used to mix nitrox (since the air used for both purposes comes out of the same compressor), so in effect it is not "air" but EAN 21 and you are in effect not switching back and forth.

And as indicated above, if you stay at or bleow 40% mixes, it wonlt be an issue.