Irresponsible or Illegal? Maybe Both!

[GNwes]

I have an 'acquaintance' who is planning on running a dive charter. This person has a boat and has acquired several 300 bar tanks with obviously, 300 bar DIN only valves. Now instead of doing what they should do, sell the tanks and buy the appropriate ones for the job, this person has decided they are going to modify the DIN valves with a screw-in adapter made by a local machine shop and I suppose drill a seat in the back of the valve for the yoke valve to seat.

I have expressed my concern to this person that I think their idea is stupid and someone could die... but they seem, well, uninterested. So my question is this. Is this illegal? and am I overreacting? or are my concerns valid?
:smt100

[FW]

My first question would be, "what pressure does he plan to fill the tanks?"

If he plans to go over 200bar (around 3000 psi) he is nuts. The insert idea is probably not DOT approved, but if he doesn't cross state lines, there isn't much DOT can do. OSHA is a different story.

[stairman]

300BAR din valves should be threaded already for yoke adaptors.

[FW]

300BAR din valves should be threaded already for yoke adaptors.
Nope, they are too deep, a yoke won't fit over them.

[stairman]

Well then he's crazy.Wait till he gets the machine shop bill.

[GNwes]

My first question would be, "what pressure does he plan to fill the tanks?"

If he plans to go over 200bar (around 3000 psi) he is nuts. The insert idea is probably not DOT approved, but if he doesn't cross state lines, there isn't much DOT can do. OSHA is a different story.
that is a good question, I have no idea what pressure he plans to fill them to, but seeing how a dive shop will normally fill them to whatever pressure the tank is rated to, I would assume 3500. But then again I may be assuming a lot.

[aainslie]

I din't think they'll get it to work. That 300 is just too deep to fit a Y over. So don't fret, grasshopper.

Edit - oops, Forrest got in before me.

[GNwes]

I din't think they'll get it to work. That 300 is just too deep to fit a Y over. So don't fret, grasshopper.

Edit - oops, Forrest got in before me.

Thats what I figured. I'm taking him a yoke adapter tomorrow so I can effectively illustrate to him how stupid he is.

[Slüdge]

The "theoretical" limit for a yoke is 232bar (3442psi), but I've seen yokes with "4500psi" stamped on them! I believe that's what the post-1995 Oceanic Balanced Piston says.

To add some real world to this, I've seen people with old Scubapro Mark 5s with 2250 yokes on them (the really skinny ones), and they put them on AL80s, which commonly are filled to 3200psi. I haven't heard of one blowing up yet, but I don't want to be around one.

To go over about 3600psi with a thick yoke is crazy in my book.

[Line Squirrel]

The OP didn't post what tanks these 300bar DIN valves are on.

If they want to alter the valve to fit an A clamp and the tanks are HP (3442 or 3500psi) tanks then forgret it, that's crazy.

But we don't know what the tanks are...I have 300bar DIN valves on all my AL80 stage bottles.

[GNwes]

The OP didn't post what tanks these 300bar DIN valves are on.

If they want to alter the valve to fit an A clamp and the tanks are HP (3442 or 3500psi) tanks then forgret it, that's crazy.

But we don't know what the tanks are...I have 300bar DIN valves on all my AL80 stage bottles.

sorry, 300 bar tanks.... 3500 psi the old PST HP's. But regardless, as you said, altering would be crazy.

[Line Squirrel]

sorry, 300 bar tanks.... 3500 psi the old PST HP's. But regardless, as you said, altering would be crazy.

I agree, I deleted my first post. Now knowing these are HP tanks that sugggestion would be a very bad idea.

[OneBrightGator]

When we were down in the Keys this past May my buddy handed me his DIN to yoke adapter saying check this out... two hairline cracks where the "sides" met the end without the knob (for lack of a better description). Anyway, his adapter is hardly used and only on rental tanks and such that aren't subject to excessive pressure. Just something to think about.

[DogDiver]

He should just put new 3000 psi yolk valvs on the cylinders. Or convertable 200 bar din/yolk valves. Screw (lol) the adaptors.....

[Slüdge]

Back the truck up! These cylinders are NOT 300bar.

300bar is approximately 4400psi. You're confusing the cylinder with the valve.

And by the way, these cylinders have the skinny neck, so you can't replace the 300bar valve with a 200bar or yoke. By law, no valve could be sold in the US for these cylinders except 300bar. (Even though I have actually seen some; they were 200bar with inserts, but were bought outside the US.)

Bottom line, he needs to buy some cheap AL80s and only let the HPs be used by divers with DIN regs.

[GNwes]

Back the truck up! These cylinders are NOT 300bar.

300bar is approximately 4400psi. You're confusing the cylinder with the valve.

And by the way, these cylinders have the skinny neck, so you can't replace the 300bar valve with a 200bar or yoke. By law, no valve could be sold in the US for these cylinders except 300bar. (Even though I have actually seen some; they were 200bar with inserts, but were bought outside the US.)

Bottom line, he needs to buy some cheap AL80s and only let the HPs be used by divers with DIN regs.

I'm definitely not confused and you are very correct. I was not to getting into specifics so I generalized. 300bar meant not LP! But either way 4400 psi is definitely HP so you point is somewhat moot.

Again I agree with you entire post and appreciate your input regarding laws.

[caver]

I have an 'acquaintance' who is planning on running a dive charter. This person has a boat and has acquired several 300 bar tanks with obviously, 300 bar DIN only valves. Now instead of doing what they should do, sell the tanks and buy the appropriate ones for the job, this person has decided they are going to modify the DIN valves with a screw-in adapter made by a local machine shop and I suppose drill a seat in the back of the valve for the yoke valve to seat.

I have expressed my concern to this person that I think their idea is stupid and someone could die... but they seem, well, uninterested. So my question is this. Is this illegal? and am I overreacting? or are my concerns valid?
:smt100

I have some old 300 cubic feet acetylene cylinders, he could modify them and rent them out to his victims.

[FW]

He can probably sell those tanks, as sidemount tanks, for more than the cost of AL80s with the right valves. Do you know the tank size?

[OFG-1]

Boy, you guys crack me up. DOT approval? Are you joking? We think nothing of sticking 3700+ psi in a lp 104, clamp a yolk Scubapro regulator on it, and go diving. How many burst disks are in your 200 bar manifold? And you want to pontificate about this poor schmucks valves.

BTW, you can buy this from GMC, file off the little thing at the end, and it will fit a 300 bar valve just fine.

http://www.gmcscuba.com/ProductInfo.aspx?productid=45185

[fitnessdiver]

Yeah- agreed, but I think the point was about liability....

What "WE" do to ourselves is one thing. As a business owner should this guy alter a tank valve --then have something happen.... is he liable?

I'd say it's really irresponsible and he is handing a very easy lawsuit to anyone who ever has a problem. I'm not even close to a lawyer but isn't there something about "acceptable standards"?? Thats going to be in his insurance right?

[skip]

the PST tanks, rated pressure 3442, have 200 bar valves (din with inserts). from my understanding valves are not rated by pressure anyway. the pressure rating comes from the equipment designed to connect to them and this is a european thing. they (europeanians) set up two valve types so the equipment could not be mistakenly connected to the wrong pressure. had nothing to do with scuba. had nothing to do with how much pressure the valve itself could handle. indeed my understanding is that 200 and 300 bar valves are the same except for depth/number of threads.

i see no problem at all making a longer insert for the 300 bar valves and putting a yoke on them. although my yoke regs won't even fit over the top of the 300 bar valve so an insert would'nt do a bit of good anyway!

-skip