Stop steering new divers in North America towards DIN regulators

[jagter]

This is not a bad idea if your diving Yoke, and traveling into DIN areas. Also having your own allen/hex key so your not wating around on the boat for the Captain/DM to remove the slug for you. (I've seen this happen)

I would just clarify that you cannot convert all DIN valves using the typical 200bar insert. a) the slug is not deep enough for some (300bar) valves. b) you have to have the 'pro' type valve with the dimple on the back to secure the yoke clamp to. You could be in major trouble if you ever came across a 200bar NON-Pro valve and tried to use a slug converter. (don't know if these even exist). ..Just make sure you have the dimple on the back!

For 300 bar, yes the insert won't be 'deep' enough, it will be 2 threads short. But as I understand yokes are only rated to 232 bar anyway. So it's really protecting you from yourself. The 300 bar valves also don't have the dimple, to discourage any determined attempts at attaching a yoke and blowing up something. And of course there is the rarity of 300 bar rental cylinders. (has anyone ever seen one?)

I've never seen a 232 bar valve without the dimple. I'm sure they must exist somewhere though, but can't think of a good reason why anyone would manufacture one.

 

[drbill]

I prefer DIN to yoke and have for almost two decades. I carry a yoke adapter which makes it easy to use my regs on yoke tanks (albeit with some reduction in safety). Most operators I've dived with have at least a few convertible valves.

 

[admikar]

This thread is about North America, per the title. 300 bar tanks and fills are generally unavailable here because of USDOT regulations.

Not being a jerk, but aren't you the land of free and land of democracy? Change the regulations?!

Probably because of the already mentioned problem of needing a true HP tank and someplace to get it filled to that high pressure.

In Europe & other regions where DIN dominates, do recreational divers have ready access to tank fills in excessive of the equivalent (since I know they probably think in metric) of 3442 PSI?

In my part of Europe, quite a few divers use 300 bar tanks, typically 10L, 12L or 2x7L twinsets, so not being able to offer 300 bar fills limits the market quite a bit. So most LDSs offer 200, 235 and 300 bar fills equally. I have the impression that many clubs also do that (non-commercial club diving is more widespread than commercial resort diving in many areas).

My club's compressor have two fill whips, both 300 bar. We also have two 300 -> 200/232 bar adapters with a 250 bar safety valve plus a DIN/yoke adapter which only fits a 200/235 bar fill whip (or adapter). Even the rather antique Bauer we bring on trips has two whips; one 200/235 and one 300 bar.

I don't know about other European countries.

My club have a compressor with 2 200 (232) bar fill whips, and a 300 bar fill whip. My friend have a compressor with one 232 bar and one 300 bar fill whip. Today, I carried tanks to a fire department that have two compressors with 2x232 and 1x300 setup. So, I think it it is safe to say that we do have a ready access to HP fills.
Edited to say: since it is a fire department,aka public service, my fills are free, provided my tanks are legal ( hydro and visual), but to be fair, fills at my club and at my friend's place are free too

 

[KenGordon]

I've never seen a 232 bar valve without the dimple. I'm sure they must exist somewhere though, but can't think of a good reason why anyone would manufacture one.

I have two. They are 3l and the knob is where the dimple would be.

 

[KenGordon]

And you're in the UK, right?

Yes, are you trying to suggest the UK is not in Europe? Oh, wait....

 

[KevinNM]

Bob,

I searched and can't find anything. Does anyone have a source for the maximum allowed pressure? I understood that a limitation to 3442 PSI was the reason 3500 PSI tanks were discontinued.

I think it was a DOT ruling about transporting high pressure tanks on the highways.

 

[JohnN]

I think it was a DOT ruling about transporting high pressure tanks on the highways.

That would make tanks used by fire-fighters rather problematic, wouldn't it ?

 

[KevinNM]

That would make tanks used by fire-fighters rather problematic, wouldn't it ?

" Although there are 3500 psi cylinders still in service, current DOT rules prohibit the transport of metal scuba cylinders on public roads with pressures above 3442 psi (230 bar), even if the cylinders have been rated for higher pressures"
Dive Gear Express® | Official Site | Dive Gear Express®

 

[JohnN]

Hmmmm, SCBA cylinders are wrapped (carbon fiber I believe) metal cylinders. . .

 

[2airishuman]

All the 4500 PSI SCBA cylinders I've seen are carbon fiber wrapped and have a 15 year life limit after manufacture.