rented out of date tanks

[rjchandler]

We must be off topic...Or perhaps I don't understand how using a scuba tank (with air) involves hazmat...

compressed gasses are Hazmzt by definition under the regs. The tires on your car are not as long as you don't overinflate them

 

[Bob3]

Yep, the "in commerce" part is where folks get away with overfilling their tanks, etc.
As long as its not a commercial entity, the hazmat rules do not (for the most part) apply to the private citizen.
Canada is a whole other ballgame, where hydros ARE required by law, individuals included.
So, chadfordr6, are you in the US or Canada?

I know of a couple local fire departments that have LARGE "shop built" high pressure volume tanks installed on a trailer that carries their compressor. They didn't even bother with nice domed end caps, just slapped some slabs of 1" plate over the ends of 12" x 8' pipe & welded it up.
Almost scary, eh?

 

[scubapro50]

I've run acrossed this problem down in Mexico. A lot of the smaller operations have used scuba tanks for the tourists. Many times these tanks are filled by the same shop running the dive. When asked they say the "tanks are safe" and there is no place local to have the hydro done. I think they were just too cheap and wanted to save money.

 

[fmw625]

Bob3 stated

Down here in the US a hydro is needed only if the bottle is used in interstate transport.

Are you sure of that?

Scuba tanks are also covered under OSHA, CFR, and HAZMAT, not just under DOT.

 

[RichLockyer]

Two key lines here:

(b) Any person who, under contract with any department, agency, or instrumentality of the executive, legislative, or judicial branch of the Federal Government, transports, or causes to be transported or shipped

in the same manner and to the same extent as any person engaged in such activities that are in or affect commerce is subject to such provisions, orders, regulations, and requirements.

This regulation specifies that a representative of the Federal Government is subject to the same regulations that apply to any person "engaged in such activities that are in or affect commerce"

Commercial use. DOT regs for compressed gas do not apply to personal usage.

I have heard of instructors being cited for carrying excessive amounts of compressed gas, or for improperly carrying compressed gas cylinders, as an instructor technically IS engaged in a commercial activity.

 

[RichLockyer]

hazardous materials carried on a motor vehicle by a private motor carrier in direct support of a principal business that is other than transportation by motor vehicle. Section 173.6(d) limits the aggregate gross weight of all materials of trade to not more than 440 pounds. ..."

So a dive instructor could carry 5 sets of double 104s and remain exempt.

 

[RichLockyer]

I know of a couple local fire departments that have LARGE "shop built" high pressure volume tanks installed on a trailer that carries their compressor. They didn't even bother with nice domed end caps, just slapped some slabs of 1" plate over the ends of 12" x 8' pipe & welded it up.
Almost scary, eh?

Okay... so now for the ultimate in a thread hijack

Assume for a moment that I am building a home fill station.
Now assume that this fill station is located in my garage... under my guest bedroom.

Not wanting a blown tank to take out a wall, or the bedroom, I would want to construct an explosion-safe containment for the fill tub.
Obviously not sealed, preferably vented to the outside of the building so as to prevent overpressure and blown windows/eardrums.

What thickness of steel plate would you think would be enough for a "tub" of about 24Dx48Lx36H? Welded or L-strapped corners bolted through?
Semi-trailer hinges and latch sufficient or overkill?

 

[TX101]

Okay... so now for the ultimate in a thread hijack

Assume for a moment that I am building a home fill station.
Now assume that this fill station is located in my garage... under my guest bedroom.

Not wanting a blown tank to take out a wall, or the bedroom, I would want to construct an explosion-safe containment for the fill tub.
Obviously not sealed, preferably vented to the outside of the building so as to prevent overpressure and blown windows/eardrums.

What thickness of steel plate would you think would be enough for a "tub" of about 24Dx48Lx36H? Welded or L-strapped corners bolted through?
Semi-trailer hinges and latch sufficient or overkill?

Well, you could probably work it out if you knew the calculations..

but I would have thought 1 inch plate would be more than enough to stop a cylinder. And welded properly, welds should be stronger than the original material - although getting good penetration on 1 inch plate is gonna need a HUGE welder.

I know cylinders have gone through cars, etc. but car body panels are actually very thin steel (like 3-5mm). 1 inch plate is what, 24.5mm? I think the walls of the cylinders themselves are no more than 10mm (for steel - more for ally).

 

[rjchandler]

Okay... so now for the ultimate in a thread hijack

Assume for a moment that I am building a home fill station.
Now assume that this fill station is located in my garage... under my guest bedroom.

Not wanting a blown tank to take out a wall, or the bedroom, I would want to construct an explosion-safe containment for the fill tub.
Obviously not sealed, preferably vented to the outside of the building so as to prevent overpressure and blown windows/eardrums.

What thickness of steel plate would you think would be enough for a "tub" of about 24Dx48Lx36H? Welded or L-strapped corners bolted through?
Semi-trailer hinges and latch sufficient or overkill?

You're taking that "price is no object"thread seriously aren't you?

 

[rjchandler]

So a dive instructor could carry 5 sets of double 104s and remain exempt.

Unless he ends up on a car ferry - then additonal rules may pop up. oh -- and that Nitrox is no ordinary compressed gas.