Deco cylinders O2 over pressurized

[Imbodie]

So I'm moving into the realm of deco diving, just finished Tek-40 and starting to work on Tek-45.. Just curious how comfortable everyone is with filling a 3000 psi cylinder with 02 that gets questionable above 2250 psi?? Back in 2011(ish) when I was working at a dive shop in Tampa there was a guy that blew out the front of his apartment (and died) most likely from an AL40 with 100% O2 in it.... I don't know all the details but this was enough to make me question getting 100% O2 filled to capacity of an AL40/AL80.

 

[Whitrzac]

Make sure everything is clean/compatible
Dont drop it
Fill it slowly

 

[Scott]

^^^
This

 

[Imbodie]

THAT is NOT reassuring.

 

[broncobowsher]

Nothing unstable about O2 above 2250. Perfectly safe at 3000 and even higher. Clean and slow and key. No slapping the valve open. Crack it slowly, let the pressure build over several seconds, once equalized then open the valve fully.

Someone put a little too much fear into you about O2. And gave some incorrect advice as well. O2 is not suddenly safe if under 2250. Just about every rebreather out there has one bottle filled with 100% O2 and if there is a booster involved, filled to 3000 PSI. Maybe more.

 

[Imbodie]

Nothing unstable about O2 above 2250. Perfectly safe at 3000 and even higher. Clean and slow and key. No slapping the valve open. Crack it slowly, let the pressure build over several seconds, once equalized then open the valve fully.

Someone put a little too much fear into you about O2. And gave some incorrect advice as well. O2 is not suddenly safe if under 2250. Just about every rebreather out there has one bottle filled with 100% O2 and if there is a booster involved, filled to 3000 PSI. Maybe more.

I guess I was basing my post on the fact that medical O2 cylinders generally contain 2k psi when full and this is my only exposure to O2 outside of diving.

 

[Wibble]

curious how comfortable everyone is with filling a 3000 psi cylinder with 02 that gets questionable above 2250 psi?

Questionable?

The O2 cylinder must be O2 cleaned and certified. All hoses need to be clean. Mustn't open valves too quickly.

If diving on open circuit, you'll always be after high pressure = boosted oxygen. This gets harder to obtain if the source pressure before boosting is lower.

I've never used 100% for deco. It's MUCH easier to use 80% which is 155bar/2250psi topped off with 53bar/770psi air to bring the pressure up to 208bar/3000psi. There's no difference in your deco times; it allows you to get on it at 9m/30ft; easier to get a full-pressure fill... what's not to like.

On my rebreather I get my twin 12 litre oxygen bank cylinders are boosted to 250bar/3600psi oxygen and decant to the 3 litre oxygen cylinders from that.

 

[Imbodie]

Questionable?

The O2 cylinder must be O2 cleaned and certified. All hoses need to be clean. Mustn't open valves too quickly.

Well there was no question about O2 cleaning or handling O2... though I am curious how you O2 clean a hose... Valves I get, 2nd stages I get... but hoses?

 

[Wibble]

Keep them clean from purchase. Put caps on the hoses when finished. Flush out the hose first (e.g. attach the hose at one end and gently release some oxygen through it). Don't get any grease on the connectors... No special treatment.

Ah, I'm talking about decanting hoses.

For your regulators, those "should" be oxygen clean at service. Same thing; keep them clean, cap them if not hung up for drying; no grease.

 

[cerich]

Nothing unstable about O2 above 2250. Perfectly safe at 3000 and even higher. Clean and slow and key. No slapping the valve open. Crack it slowly, let the pressure build over several seconds, once equalized then open the valve fully.

Someone put a little too much fear into you about O2. And gave some incorrect advice as well. O2 is not suddenly safe if under 2250. Just about every rebreather out there has one bottle filled with 100% O2 and if there is a booster involved, filled to 3000 PSI. Maybe more.

You are wrong on most of that.