Refilling Oxygen Cylinders

[BossyCow]

We have a cascade system for the air bottles for fire SCBA's but O2 is refilled professionally.

 

[jafo]

We're rural, cascades for both air and O2. Never thought much about it except that it is a convienience to fill your own bottle after a job. Been working with compressed gas since I was 14 (O2, Acetylene, Nitrogen, Helium, argon, etc.).
However I cringe when I see how many EMT's and F/F's fill tanks. It works just fine if you follow the training Exactly, and EVERY time you fill tank, Understand the gasket issues with O2 (use an o-ring gasket, not plastic), don't talk to someone else when you do it, and TAKE YOUR TIME. These are not toys, be careful.
Jafo

 

[Gbro]

KEVD18 posted,
ive also seen it done opening the m tank valves very quickly without a problem on a regular basis.

There very well may be a flow control devise(like a fixed orifice) incorporated with the filling assemble, as filling too rapidly will create heat. Just like a diesel engine. One can tell the difference by listening to the flow rate. If you open very slowly and listen, as you proceed to open you may notice there is no further increase in the flow past a certain valve position. This should be done only with a empty cylinder and only for a very short time in case there is no protection. You may also inspect the CGA(compressed gas association) fitting that attaches to the M cylinder for an orifice. Each CGA fitting should be alike.
Please use caution and learn everything there is to know about what you are doing.

I am surprised, I thought more services used a vendor service to supply cylinders for exchange.
I would like to see my old service change to vendor supplied. Its a $$ issue.

I will dig out the failed safety release valves from a couple of incidents, as there is no room for error in working with compressed gases.

 

[CFRBryan347768]

All

of ours are sent out i believe.

 

[paramedix]

I started off with the cascade system at my volunteer station. The problem we had is when you dont know how the system work, you can stuff it up completely and not even to speak about the SAFETY RISKS....

I am so glad that the company I'm working at now, provide o2 already filled with fixed regulators. The company that provides it bears the insurance as well...

 

[emtd29]

We cascade our "D" tanks. Only those trained and qualified on the system are authorized to use the system ( I being one of those people)
( 6 "H" tank system with a steel box type unit that the "D" tanks are put in. The unit has a safety interlock that unless the small tank is secure and the hatch closed and locked, the system will not pressurize)

Everything else ("M" and "H" tanks) is sent out

 

[medic417]

So easy a basic or even a fire fighter can do it. A cascade is easy to use if a person has any common sense. Biggest problem is some try to fill to quickly. Do not get in a hurry. Double check that all fittings are secure. We use a cascade to fill the D's, E's, and M's. A supply company brings the large tanks for our cascade system.

 

[Gbro]

So easy a basic or even a fire fighter can do it.

Are you saying "A Cave Man" can't be an EMT-P?
I could send a couple of pic's from one of the ne'er by ALS services.

 

[ffemt8978]

So easy a basic or even a fire fighter can do it. A cascade is easy to use if a person has any common sense. Biggest problem is some try to fill to quickly. Do not get in a hurry. Double check that all fittings are secure. We use a cascade to fill the D's, E's, and M's. A supply company brings the large tanks for our cascade system.

Easy...yes. Is it the smart thing to do? Not necessarily. Do you perform all of the required checks on each cylinder before you refill them, and do you document such? I could go on, but I'm willing to bet that most agencies that cascade O2 don't do this.

 

[JPINFV]

Huh, there's supposed to be some sort of documentation before filling up a tank? News to me, but my old company wasn't exactly top of the line or the most intelligent.

 

[Jon]

Same. I'm on an FD and for our ambulance, we use the cascade and once the big tanks are empty/too low, I believe they're replaced either by us or a company. And for the ambulance O2, we would just replace the entire tank.

I've only used it once. I kinda forgot to close the valve on tank 1 when switching to tank 2...thus equalizing the two tanks. It wasn't an issue (except a mistake on my part, which I have learned from!) with the dept, as the tanks were low as is. However, our cascade system for the SCBAs is similar, but if you equalize the tanks, it's not a big deal because it's just the air we breathe (...filtered though) and can be easily refilled.

But I do agree with many poster's above in saying it's dangerous. Gas=pressure. Too much pressure=bad=it go boom! h34r:

At the small "mom-and-pop" transport ambulance Co. I worked at a few years back, I was the only field employee who was allowed to use the cascade, because I demonstrated that I could use it in front of the Ops. manager, and he trusted me. The Owner and the Ops manager were REALLY upset about the cascade, becuase the month before, some yahoo had equalized the high pressure tank with the low pressure tank... this was a HUGE deal because the service was VERY small, and oxygen was a big part of their ongoing expenses... and having to replace a brand new H-size cylinder made the tight-fisted owner VERY upset.

But now that I'm older and wiser... I agree with FFEMT... if you don't test the tanks and system appropriately, there is a HUGE problem.

At EMS Today I spoke with a few of the vendors selling O2 cascade systems... NOT ONE was displaying a fill port. 2 of the three vendors told me they didn't bring them "because it is too heavy". Does it bother you that you need that much protection to safely use a cascade?