Nitrox cylinder bands

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Do any local FL shops still do this Partial Pressure blending? Or is it mostly a foreign thing?
I'm sure there are quite a few in Fl that still do this. It's quite the accepted practice. How they make NitrOx should be one of the questions you ask before you have a cylinder filled. Also find out what their requirements are to have that tank filled. Don't argue if you don't like the answers, just ask the next shop. We have lots of shops here in Florida.
 
Do any local FL shops still do this Partial Pressure blending? Or is it mostly a foreign thing?
It is the norm almost anywhere that a shop does not do enough nitrox business to justify the cost of any kind of blending system. In Colorado, for example, we have no truly local diving that is deep enough to justify the use of nitrox, so we only use it when we travel out of state. Most of our out of state travel is dedicated to OW instruction, so most of that does not justify the use of nitrox. The shops that provide nitrox do it through PP blending (as far as I know), and Most of the shops in the state do not even have the ability to do that.
 
I'm not sure what kind of blending my shop does, I just know it's not partial pressure. :)
 
Peter69_56:
TDI issue a sticker which clearly just says oxygen clean. It appears a LDS issues a sticker which states clearly "cleaned for Nitrox to 40% or oxygen clean to 100%.
The TDI sticker is dual-purpose, and you can punch the lower 'star' (as in your picture), or the upper star if the cylinder is not cleaned for oxygen service. We use a similar sticker (although not agency-labelled) at the shop where I currently do the VIPs. For the majority of enriched air cylinders, I punch out the upper 'star' as the cylinder is NOT cleaned for oxygen service. PADI offers two separate stickers, one of which is labelled 'NOT OXYGEN CLEAN' and the other is labelled 'OXYGEN CLEAN'. BUT (and this is a big 'but' which doesn't adequately cover my 'butt' as the VIP person, from my perspective), even though the upper 'star' on the dual purpose sticker, and the small print on the PADI 'NOT OXYGEN CLEAN' sticker both imply some 'cleaning', there is none done.
 

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Do any local FL shops still do this Partial Pressure blending? Or is it mostly a foreign thing?
Force-e in WPB only does pp fills for nitrox and I think that is true with all their shops including the one in Pompano but not certain. Another shop in WPB that I use for O2 fills will do pp if you need a mix they don't bank and it will cost you more per fill.
 
I'm not sure what kind of blending my shop does, I just know it's not partial pressure. :)
Your safety is your primary job. Be proactive in this regard. Ask to see their operation. Ask to see their clean air certificate. Is it over six months old? How do the compressor and fill banks look? Do they have a time tracking method for their filters? Do they have replacement filters in stock? Not only do you have a right to be nosy, you owe it to your family. We own two CO analyzers and three O2 analyzers and travel with them for this very reason.
 
It is the norm almost anywhere that a shop does not do enough nitrox business to justify the cost of any kind of blending system.

It also seems to be the norm here in NJ, where almost every shop does an awful lot of nitrox business. Perhaps because so many local divers like to dive best/custom mixes for whatever specific dives they have planned? Doesn't really make sense to blend/bank a "standard" mix when the standard is to dive nonstandard mixes.
 
what John said is a common misconception... A properly set up continuous blending system is actually MUCH more cost effective than PP blending. With a blending system, which you can build for under $300 with an O2 analyzer attached to it... you don't have to O2 clean anything other than the dosing system which is just a needle valve, so NBD there, so no more O2 clean whips. No more dumping of tanks and having to put more compressed air into them to top them off, and no cost of cleaning all of the tanks. Now, dive shops will use this is a way to make more money, because they charge a lot of money for O2 cleaning, and more for nitrox fills. On top of this, the continuous blending systems can suck O2 bottles dry so you have less waste, where a PP blending system often leaves a significant amount of O2 left in the bottles that you can't do anything with.

PP blending for "standard" mixes, or even custom mixes if you go through the compressor is a perfect example of being penny wise and pound foolish, but that is the reality in this industry...
 
I avoid Partial Pressure blending whenever possible. I've been poisoned twice with CO due to this.
I have to admit that this baffles me. Why should PP blending increase the risk of CO poisoning?
 
A properly set up continuous blending system is actually MUCH more cost effective than PP blending. With a blending system, which you can build for under $300 with an O2 analyzer attached to it... you don't have to O2 clean anything other than the dosing system which is just a needle valve, so NBD there, so no more O2 clean whips. No more dumping of tanks and having to put more compressed air into them to top them off, and no cost of cleaning all of the tanks.
Tom makes a very good point. I 'grew up' doing partial pressure blending, but I did so in a shop that had a truly outstanding fill station set up, plus a 4500 psi booster pump. We could, and did, blend just about everything - enriched air, normoxic and hypoxic trimix, heliox. etc. I loved it. We could, and did, boost 100% O2 to 3000 psi (OK, some will say that was crazy, but we did it, A LOT, without incident. I loved splashing with my 100% deco bottles filled to 3000psi. :)

But, all good things come to an end, and so did that shop. I moved to a shop where we do continuous blending. My first reaction - what a pitiful set-up. But, once I started using it, started thinking about the possibilities, etc., I realized we can do almost what I did before, with the exception that there is no booster pump, and it is actually easier. I am working on a plan for a control panel to allow us to add trimix capabilities. If volume becomes an issue, we can even add a second Stik station (we don't have the capacity to bank enriched air). I am now a beleiver, in the efficiency and the cost benefit.
Now, dive shops will use this is a way to make more money, because they charge a lot of money for O2 cleaning, and more for nitrox fills.
Frankly, most dive shops have no interest in doing oxygen cleaning. I did it for my old shop for many years, and I do it on a limited basis for my new shop. It is a PITA, it is time-consuming, and the compensation doesn't come close to matching the time investment. I am happy to move away from PP blending, oxygen cleaning, etc.
 

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