Scariest Air Fill of my Life!

[knotical]

Do they not have to be certified to operate this type of equipment . . . ?

afaik, anyone filling cylinders for a commercial operation is required to have function specific HazMat training (I think it’s in the CFRs). I don’t know whether it requires training on all combinations of equipment for which the system is capable, but think it should. When I got HazMat training, I’d already been filling for a while.

 

[Garrobo]

ianr33: At your local fire station. They could use the money.

 

[caymaniac]

I had a guy fill my steel 72 to 3300 and the burst disk never blew, I let out alot of air after I put a gauge on the tank!

 

[Aeropl]

It's a small world -- I laughed when I read this because I'm pretty sure I had a funny experience at this same shop yesterday with the same guy. I have only been to this shop twice before: once a while ago to get my tank VIP'd and another just a few days ago to get a hood before my spring dive. So I stopped by to drop off my tank yesterday and I had to show the guy where the VIP sticker was, even though it had this shop's logo on it and was about 6" square. Next I asked to exchange the hood which I didn't use (this was obvious because the two paper tags were still attached and in perfect condition) for store credit. Immediately after picking up the two tags on the hood to look at the price, he asked in a serious tone if I had used the hood for my dive. I explained in the nicest way possible that there's no way I could use the hood for a dive and still have the two tags attached and not disintegrated. I was pretty amused after dealing with the classic "new guy."

 

[mike_s]

I got a nice fill once. Won't name the shop, I like them, but it did freak me out a bit.

I took my AL100 in for a fill. 3300 rated, 3500 for a hot fill is OK by me. I checked the mix but not the PSI, put it in the car.

The next morning, after it had cooled all night, we're gearing up for a beach dive. I mount my 1978 Mk5 yoke regulator to it, crack the valve & ease it on to pressurize. Imagine my surprise when my gauge read 3950

We got in the water quickly & started breathing it down. Longest single tank dive I've ever done

I had a similar experience with one of the shops down in Panama City.

They were filling my AL80's. I looked at one of the presure gauges on the walls reading 3800psi thinking it was a bank/cascade pressure.... then I realized the pressure was rising, not dropping (as it would be out of a bank).

I asked the guy filling my tank "Is that the pressure of my tank you're filling".

He looked at the gauge and went "OH CRAP!!!, what do you want me to do????" (as the pressure kept rising... in a panic)

I replied "I suggest you let some air out of it before it blows....", which he did quickly......


Some people just don't need to be filling tanks......

 

[ClayJar]

afaik, anyone filling cylinders for a commercial operation is required to have function specific HazMat training (I think it’s in the CFRs).

We covered the little hazmat training in the PSI VCI course I took. If you handle compressed gas commercially (fills or what have you), you should have had hazmat training.

From what I recall (and I'm not looking it up this late in the evening), it was not required that you use any specific training (although PSI has pre-made materials available, if you want to have someone else to point to), but training of some type was required.

 

[h90]

well the DM who tried to screw my DIN Reg in the Yoke tank....for sure 1 min turning it arround in the not existing hole...

 

[DA Aquamaster]

I had a guy fill my steel 72 to 3300 and the burst disk never blew, I let out alot of air after I put a gauge on the tank!

The hydro test pressure for a 2250 psi service tank is 3750 psi and the bust disc is required to burst between 90 and 100% of that pressure - a range from 3375 to 3750 psi.

So not having a burst disc blow at 3300 psi on a steel 72 is not surprising as long as the burst disc is fairly new and in good condition. On the other hand pushing it that close to the burst pressure is not good for the disc and will make it more likely to fail in normal service at normal pressures later. In generla the burst pressure of the disc degrades as it ages, corrodes, experiences fill cycles, etc anyway and an overfill that large degrades it much faster.

In the future if that happens, I'd ask them to replace the burst disc assembly free of charge.

 

[LiteHedded]

wait....UCF????
GO KNIGHTS!

 

[Zoomer]

The purpose of the burst disk is to protect the tank if left unattended while filling it from a running compressor, and possibly protecting the compressor, though most have their own pressure relief valve. They are designed to burst at well above the tank rating - often around 40% above nominal. For an aluminum 80, that would be:

3000 PSI x 1.4 = 4200 PSI.