Main crash concern transporting Scuba tanks?

[Schwob]

the department of transportation has specific rules regarding the transportation of high pressure cylinders. they must be secured. they cannot be in an enclosed vehicle. they must be able to discharge directly in the atmosphere.( read in an open truck). check your federal and state regulations regarding transportation.

Is that for any quantity of tanks / compressed gas tank size or gas volume or for a quantity exceeding a specified threshold?

I secure my tanks anyway as I am quite aware of what might happen in a crash and as that is my main concern, but this requirement about "not in an enclosed vehicle, venting directly into open air" I would be violating... if it applies to me / my quantities that is.
That requirement may make a lot of sense for many gases, OTHER THAN AIR, (maybe including for oxygen) but if it indeed is a requirement for compressed air as well, then... "oh well, government"...

Jeez, really, is that enclosed scuba/rough camping converted utility trailer going to have to be an "outlaw"?

(If that constitutes derailment of thread, maybe it needs to be split of)

 

[txgoose]

I'm going to say that if "heavy things are flying around" that you're probably dead.

R..

Isn't that why I mentioned Concern A? Granted I hope to never be faced with the impacts described in your post above. We can start another thread debating the differences between "flying around" and "shifted" and which agency defines that most conservatively.

 

[Patoux01]

I figure that if we get to "missile" state, the wreck was probably big enough that the forces of acceleration from the impact are hundreds if not thousands of times greater than the momentum of an air powered tank.

Well, there's quite some energy in a tank. And on tests where they decapitate a tank, they sure fly far away.
And personally I wouldn't want to have my face in front of that thing.

But heavy things moving at high velocities and not being properly secured lead to some issues too.

@Schwob "That requirement may make a lot of sense for many gases, OTHER THAN AIR, (maybe including for oxygen) but if it indeed is a requirement for compressed air as well, then... "oh well, government"..."

What would happen if you suddenly release 3000l of air in your car?



I'm personally more on side A, so my tanks are always secured properly nowadays. They weren't when I started and hadn't thought about "what would happen with 40kg of steel lying behind me and I go from 130km/h to 0 in about no time?". Not saying they'd fly right through the seats, but it is likely to feel nasty for a long time (remember those kids kicking in the back of the seats...)

 

[Doc]

C) I spill my Triple Vente Grande Mocha Latte with Soy Milk.

 

[Schwob]

C) I spill my Triple Vente Grande Mocha Latte with Soy Milk.

... dang...

 

[txgoose]

Well, there's quite some energy in a tank. And on tests where they decapitate a tank, they sure fly far away.
And personally I wouldn't want to have my face in front of that thing.

I don't disagree, only saying that in a vehicle, it probably took a LOT of external force applied to the car before the valve was sheared off. That force has already put a ton of stress on your body. If I'm in a wreck, and that wreck was big enough to shear off tank valves, and my body was in front of the tank when its valve got sheared................... even diving, we can only plan for so much. At some point if it is your day, it is your day.

 

[Schwob]

@Patoux01 :
You write:
What would happen if you suddenly release 3000l of air in your car?
---
I don't think much would happen. I don't even think it would blow out a window. Certainly not if it's a burst disc. But even if it is a sheared off valve, a closed car has plenty of openings larger than a tank neck, possibly even larger than a tank diameter all together. Do you think the gas release could be sudden enough something would happen? I think not.
Now, if a tank (say one w/o burst disc) somehow managed to suddenly and catasrophically rupture.... Yeah, my car's burst discs (aka windows) might go... So might my earsdrums maybe (that would suck)... Worse??? Not sure. Think not.
Might I see that wrong? Maybe... I am willing to learn better...
How, what could happen?

Concern about "A": we agree

Missile from sheared off valve:
Yes, it could happen, but what is the liklyhood that it happens and happens such that the tank indeed becomes a fastmissile (and not a spinner)? I definitely just secure my tanks as if they don't fly to begin with the chances that the valve gets sheared of should be further diminished yet.

Edit:
On second thought:
To keep it simple, if ny car's interior was hermetically sealed (certainly is not) and had a volume of 80cf and if a full 80cf tank raptured catasrophically in half somehow, releasing all gas in an instant, the car's interior pressure would double to 1bar overpressur (or 2 atm) right? I am just not so worried about it because it very inlikely to happen extremely sudden and of course a car's interior is not that sealed...
Wrong thought?

 

[CuzzA]

This is kind of interesting to me because there seems to be a higher concern about scuba cylinders, but how many of us place equally heavy items in our vehicles with no regard. I'm sure we've all transported a 40lbs. bag of concrete or sand or a five gallon bucket of paint. Is anyone tying that down?

 

[kelemvor]

This is kind of interesting to me because there seems to be a higher concern about scuba cylinders, but how many of us place equally heavy items in our vehicles with no regard. I'm sure we've all transported a 40lbs. bag of concrete or sand or a five gallon bucket of paint. Is anyone tying that down?

That's nothing! I once transported a 300lb human and a 70lb dog at the same time.

 

[Schwob]

This is kind of interesting to me because there seems to be a higher concern about scuba cylinders, but how many of us place equally heavy items in our vehicles with no regard. I'm sure we've all transported a 40lbs. bag of concrete or sand or a five gallon bucket of paint. Is anyone tying that down?

Oh, paint. As a kid on the Autobahn I witnessed a station wagon rear ending the vehicle in front. We (my grandma driving) just barely managed to stop in time. Out came two nuns in blavk nun-dresses, wingy hats and all just DRENCHED in white paint...
... shaken up, dripping white, looking quite funny despite the situation, otherwise OK...

But heavy object that don't disintegrate are of concern to any occupant... and anything on the roof is of concern to anyone in front of you...