"Industry Standards (US)" What are they?

[ktomlinson]

The below reference applies to Commercial diving and specifically does not apply to recreational diving operation.

Reading the full text of the CFR is left as exercise for the reader.

Hint: read Luxfer's summation:

http://www.luxfercylinders.com/freq...linders-in-oxygen-enriched-and-oxygen-service

That is a great link for this thread as it lists the differences in o2 handling standards.

 

[Scared Silly]

BLUF: Luxfer says they are a member of the CGA so they support the CGA position of 23.5 %. It really is sad that, with so much real world experience with HP O2 concentrations up to 40%, no one can even attempt to make a case based on accident/incident records. I will continue putting up to 40% O2 in my scuba cylinders with absolute confidence that it is safe.

You are forgetting that Luxfer makes cylinders for other uses. I bet that the number of O2 cylinders made for medical usage out weighs the number made for scuba. Especially so today given they quit making scuba cylinders. That said I bet they are taking a collective view point - not too mention a CYA. So until CGA wants to make a different standard they are going to go with the flow.

The regs leave adequate wiggle room to go either way and the record says it is safe.

If that is what you beleive why don't you take on the project of getting CGA/DOT/OSHA to do some rule making. It is quite an educational process.

I believe that the OSHA regulations exclude recreational diving at least in part because OSHA governs workplace environments, not home or recreational environments. This is a guess on my part, but I suspect that they simply don't feel that it's in their domain to try to regulate non-workplace activity. It invites more flak to do so, and any administrative organization tries to avoid that. But clearly one cannot interpret their exclusion of recreational scuba from the 40% practice as an indication that recreational scuba should be subject to more stringent regulations than commercial diving.

It is my understanding that the history of the 40% rule came from caisson workers. While OSHA does not regulate private recreational scuba, it does regulate commercial recreational scuba. So by defacto private recreational scuba gets regulated when utilizing commercial recreational scuba.

Here is a simple example you are not required to wash your clothes but if you send a garment back to the mfg it must be clean. If not they will wash it and charge you for the cleaning. Getting a cylinder filled is the same. The difference is that for the garment industry the standard is clean and not sterile. For cylinders the standard is sterile (O2 clean) but for some applications clean (<40%) may be sufficient.

The luxfer language is a great example of liability avoidance, pure and simple. It specifically refers to their tanks only. They don't want any part of a scuba-based lawsuit, and I suspect that scuba is a fairly small percentage of their product business.

I have yet to see any hard evidence of a single incident of recreational nitrox combusting, ever. Maybe one exists, if so I'd be interested in it. Partial pressure blending excepted, of course, as that is 100% O2 handling.

There simply cannot be any arguing that the dive industry norm, as taught in all recreational nitrox classes by the major agencies, usually at the very same shops providing nitrox fills, is that under 40% O2 requires no special handling. Whether or not anyone thinks that is reckless, or even that it breaks federal regulations or recommendations, is irrelevant, and just another example of the confusion and mis-information that perpetually follows nitrox use like a dark cloud.

You are right - the anecdotal evidence does seem to say that <40% does not require special handling. And as I have said before if DEMA really wanted to do something positive for the dive industry they should be pushes for rule changes. However, perhaps they and others have and collectively CGA/DOT/OSHA have found reason not to change the rules. Which is why I have suggested to AWAP that he do some writing.

In the mean time the rules are the laws (in some cases). We may not like them. Shops may ignore them (to their detriment if ever an accident). But just gripping about them ad nauseum does not do anything. A few folks have tried to educate themselves and that is great. And a few have called BS on shops which is great as well (when it is really is BS).

 

[redacted]

You are forgetting that Luxfer makes cylinders for other uses. I bet that the number of O2 cylinders made for medical usage out weighs the number made for scuba. Especially so today given they quit making scuba cylinders. That said I bet they are taking a collective view point - not too mention a CYA. So until CGA wants to make a different standard they are going to go with the flow.


AWAP - you sound like you have bee in your bonnet so why don't you take on the project of getting CGA/DOT/OSHA to do some rule making. It is quite an educational process.

Because it would make little difference. Shops that are PP blenders will support the 23.5% standard. Shops that bank will continue to support the 40% or they will unnecessarily lose business. If the correct answer were clearly 23.5% then the PP blenders would be taking legal action against the 40%'ers to increase their share of the market.

It is not a safety issue. It is not a legal issue as the standards are not clear and consistent. It is a $$$ issue with the PP blenders wanting to sell O2 cleaning service and nitrox.

 

[Scared Silly]

Because it would make little difference. Shops that are PP blenders will support the 23.5% standard. Shops that bank will continue to support the 40% or they will unnecessarily lose business. If the correct answer were clearly 23.5% then the PP blenders would be taking legal action against the 40%'ers to increase their share of the market.

It is not a safety issue. It is not a legal issue as the standards are not clear and consistent. It is a $$$ issue with the PP blenders wanting to sell O2 cleaning service and nitrox.

AWAP you are losing credibility fast here - yer talking out yer butt. How do you know it would make little difference? Have you even made one phone call and talked with someone at the CGA ????

A shop with a concern would not take any legal action they would file a complaint. Do you even understand how OSHA / DOT works? OSHA is work place related and typically does not get involved unless you are an employee.

How to File a Complaint with OSHA

How DOT works I am unsure as they have many divisions but I have been successful in getting their attention with an aviation related complaint.

How do you know it is not a safety issue? All you can do is present your narrow scoped anecdotal evidence. Which at times can be sufficient but perhaps not. Perhaps the issue is not with today's modern regulators and cylinders that are typically come "nitrox" compatible but with all the older gear that is out there. And they may not be using nitrox so it is not yet an issue.



Finally, I am not advocating that the 23.5% rule followed or ignored for <40% O2. What I am advocating that is that perhaps it is time for the industry to get their shiit together and figure it out. In the mean time, I have 14 cylinders to O2 clean cause they just got back from hydro and they will likely get PP filled at some point. So I have no dog in this fight other than to call BS.

 

[redacted]

AWAP you are losing credibility fast here - yer talking out yer butt. How do you know it would make little difference? Have you even made one phone call and talked with someone at the CGA ????

A shop with a concern would not take any legal action they would file a complaint. Do you even understand how OSHA / DOT works? OSHA is work place related and typically does not get involved unless you are an employee.

How to File a Complaint with OSHA

How DOT works I am unsure as they have many divisions but I have been successful in getting their attention with an aviation related complaint.

How do you know it is not a safety issue? All you can do is present your narrow scoped anecdotal evidence. Which at times can be sufficient but perhaps not. Perhaps the issue is not with today's modern regulators and cylinders that are typically come "nitrox" compatible but with all the older gear that is out there. And they are not using nitrox so it is not yet an issue.

Actually I have had a bit of hazmat, OSHA, and safety (risk management) training.

I must admit, "safety issue" may not have been the best choice of words. I know it is not a recognized and demonstrated danger. Obviously there are folks trying to make it a safety issue. Without some evidence of a danger, I hope they fail as I do not wish to pay for unnecessary protection.

So, tell me, with your concern about this matter, do you avoid dive operations and locations where you could be exposed to the "dangers" of uncleaned nitrox tanks?

 

[Scared Silly]

Actually I have had a bit of hazmat, OSHA, and safety (risk management) training.

Ah like me a bit of knowledge and dangerous .

I must admit, "safety issue" may not have been the best choice of words. I know it is not a recognized and demonstrated danger. Obviously there are folks trying to make it a safety issue. Without some evidence of a danger, I hope they fail as I do not wish to pay for unnecessary protection.

Okay as you have a bit of risk management knowledge, what is one factor that often dominates most rules? The lowest common denominator factor. That is rules are often made the person with perhaps the least experience and or knowledge. The person filling cylinders is affectionately known as the fill monkey. While not always appropriate it sets the stage. Now let add in two other factors high pressure gas which can go boom and high percentages of O2 which as Sarah would say burn baby burn (well not quite as we all know that O2 does not burn but is needed for combustion). Each alone are hazmat issues and we are now combining them together.

So while we would like to live in utopia and never have someone fill an unclean cylinder with a high percentage of O2 it can happened. For instance, the O2 monitor is going out and what someone thought was 32% they were banking is actually much higher which just might be enough to cause a problem. Say it will not happen, ever gone in to get a certain percentage of nitrox and gotten some else. Ever had your cylinders accidentally overfilled (not talking a cave-fill) or under filled.

So I suspect, note suspect these reason for the CGA rule staying at 23.5% is for all the dumb azzes out there. I have no proof of that but that would be my educated guess. And I am sure the insurance underwriters have their hand in it as well. While the 40% is fine once mixed and verified. Which again it is my understanding goes back to caissons days when the gas they used were delivered and it was their equipment (not cylinders) that had to be exposed to less than 40%.


Personally, I am rather ambivalent as I have not seen enough evidence. There is reasonable anecdotal evidence that <40% is okay in cylinders but I have not seen counter evidence. Which is really is what is needed. I am sure it out there. How much and to what degree is unknown to me and most. Which is why I have suggested writing GCA/DOT which as a rule making body they would have it.

So, tell me, with your concern about this matter, do you avoid dive operations and locations where you could be exposed to the "dangers" of uncleaned nitrox tanks?

Like everything "it depends"

 

[redacted]

Ah like me a bit of knowledge and dangerous .



Okay as you have a bit of risk management knowledge, what is one factor that often dominates most rules? The lowest common denominator factor. That is rules are often made the person with perhaps the least experience and or knowledge. The person filling cylinders is affectionately known as the fill monkey. While not always appropriate it sets the stage. Now let add in two other factors high pressure gas which can go boom and high percentages of O2 which as Sarah would say burn baby burn (well not quite as we all know that O2 does not burn but is needed for combustion). Each alone are hazmat issues and we are now combining them together.

So while we would like to live in utopia and never have someone fill an unclean cylinder with a high percentage of O2 it can happened. For instance, the O2 monitor is going out and what someone thought was 32% they were banking is actually much higher which just might be enough to cause a problem. Say it will not happen, ever gone in to get a certain percentage of nitrox and gotten some else. Ever had your cylinders accidentally overfilled (not talking a cave-fill) or under filled.

So I suspect, note suspect these reason for the CGA rule staying at 23.5% is for all the dumb azzes out there. I have no proof of that but that would be my educated guess. And I am sure the insurance underwriters have their hand in it as well. While the 40% is fine once mixed and verified. Which again it is my understanding goes back to caissons days when the gas they used were delivered and it was their equipment (not cylinders) that had to be exposed to less than 40%.


Personally, I am rather ambivalent as I have not seen enough evidence. There is reasonable anecdotal evidence that <40% is okay in cylinders but I have not seen counter evidence. Which is really is what is needed. I am sure it out there. How much and to what degree is unknown to me and most. Which is why I have suggested writing GCA/DOT which as a rule making body they would have it.



Like everything "it depends"

That lowest common denominator rational would be quite useful in ending all recreational nitrox diving as we would be O2 cleaning every tank before each fill. Sure, we could go to the European/Scubapro reverse threads to reduce the risk of a tank being connected to an unclean gas source but that is just one more of the many dumbass pitfalls we could still run into even with a 23.5% standard.

The key in your post is the acknowledged lack of counter evidence.

And, no, I have never run into a tank fill that was more than 1% higher than expected. But I have never used nitrox that was PP blended.

 

[ktomlinson]

I think we can all agree on at least one aspect of this topic, and that there are many conflicting regulations. It's not as easy as one would think to figure this out, as the many pages of this thread illustrate. I think that part of the issue is that some of the pamphlets we are supposed to rely on are cost prohibitive unless you need them for your job. If a law points to an association pamphlet for guidance it should be made freely available.

 

[Scared Silly]

If one looks at the history there is not so much conflict. Think in terms of when the rules went into place and for whom. As I mentioned it is my understanding that the rules started for caisson workers. BITD the gas was mixed at the plant and delivered on site. So DOT was involved further the gas was made only via partial pressure blending. So DOT said 23.5% and above needed to be cleaned (probably came from the aviation side). Now the gas is on site and OSHA got involved and said the evidence shows that < 40% O2 which was their max mixtures were safe without special handling. The system worked fine and no real conflicts because the process was rather separate.

Move forward to the 90s and recreational divers getting nitrox mixes. The plant moved from a gas supplier to a dive shop. It started out with only PP blending. No conflict. But then someone said screw that, made a mixing stick, ran the O2 through their compressor, and banked Nitrox. Now the technology allows for affordable membrane systems etc. So now three different ways for obtaining nitrox. With PP still being the lowest common way. Thus the rules remain because of that and the human lower common denominator.

The conflict has come because of the scuba industry has not always been honest with their customers - just look at the whole 6351 cylinder issue and my compressor my rules BS.

 

[NAM001]

It looks like i willhave to inject another story of 40%. The source as told to me was with nasa and the apolo launch pad fire. It goes like this: After the fier nasa looked into preventive measures to prevent the loss of life from a fire in the future. botom line was that o2 content >60 percent acted as pure o2 and < 60 acted like air. at the same time nooa was doing the ean thing and had 32 and 36%. to provide a bufer for the nasa60% number and the divers 36% figure they settled on 40%. The 40% took into consideration that non professionals would be handling this concentration in the scuba world. Hence <40 treat as air >40 treat as 100% o2. later the feds acknoledged that they could not effectivly regulate the air industry in the ever changing techologies pluss that fed regs always were years behind teh problem. So they ruled that handlilng and such be done in acordance with standards and recommendations of agencies such as cga dot and osha whose recopmmendations were more real time as opposed to fed hindsight. Those agencies figured out tht they were now on the spot for a misshap if handled per their recommendtions. Eventially someione came up with 100%o2 of 50 psi or greater under the right conditions could cause a problem. So when you apply that aspect to a pp blending in a oil contaminated tank and slam the tank instantly with the pure o2 or during the top off with air you could get an explosion. On a 1600 psi bottle the 50 5si o2 would result n a 23.5% mix. originally the attempt was that all systems above 20% was to be o2 clean. then cga had to accept that air is 20.9 adn that all gas stations would have to o2 clean thier tire filling systems prior to each use. Then the level went to >21% adn they found that there was 4-5 places in the usa where the ambient o2 was gerater than 20.9 so they settled on 23.5. Stories are stories. The psi folks consider any mix > 23.5 which could have been pp blended would violate teh 50psi thing and that is what they teach. If i remember they even state that in thier books. Now the question might be ,,,,,because there is a requirement that only a PSI qualified inspectors are allowed to inspect the fiber tanks,,,, are the psi folks inclulded in the list of agencies whose regulations are required to be followed by fedreral statute.

Oncce again i am not saying i agree with them only passing on info. If this was not in the psi material perhaps it was in hte o2 cleaning course material i have somewhere.

---------- Post added March 20th, 2013 at 05:25 PM ----------

100% on target. And if a shop wants to know what he has to do and be protected they will go to he libility provider and ask them what they want. Any guess what they will say, knowing they will take an even more cautuos position. How wouldthe sourt se thngs. Some one brings in a contaminated tank and gets an nitrox fill. dies berathing it and the plantif lawyer says """"shop owner show us your records of your o2 cleaning of piping in your system. Well shop owner since you can't prove your system was clean, how do you know the contamination in the tank did not come from your compressor sytem. Many places i've been to no longer fill nitrox because of that. or the liability costs to cover nitrox fililng in thier insurence coverage.
.

I think we can all agree on at least one aspect of this topic, and that there are many conflicting regulations. It's not as easy as one would think to figure this out, as the many pages of this thread illustrate. I think that part of the issue is that some of the pamphlets we are supposed to rely on are cost prohibitive unless you need them for your job. If a law points to an association pamphlet for guidance it should be made freely available.