Tank?

[g1138]

agree with Prostar - if you manage to shear a valve off whilst you're driving, you've just had a major collision and probably won't be in a position to worry about exploding tanks. You probably won't be in much of a position to worry about anything at all, actually.

The easiest and most convenient way is to load the tanks horizontally with the valve pointing to the rear of the vehicle - this just makes it easier to get the things in or out.

Remember that a tank can withstand 3000psi of pressure every time it's filled - a few knocks are not going to cause them to explode. If they did, I would be long dead by now and pretty much every boat I've ever worked on would have sunk.

Load them securely, drive carefully, and don't worry about it.

Cheers

C.

I don't think that's the best choice of reasoning Crowely.
Convenience and safety don't always go hand in hand.
It's very unlikely for a tank valve to shear off, but in the unlikely case that it does, you now have a 20lbs rocket with 3000psi of thrust behind it aimed right at you.
A bit more if you use HP tanks.
So if you were in an accident and had a tank shear, then yes, in fact you WOULD be in a position to worry about exploding/rocketing tanks. Air bags don't do much good for secondary impacts.
Not even suprise bu****x jokes can make up for a situation like that
Better to position tanks sideways or with the valve pointing towards the passengers.

 

[Crowley]

I am fully aware what the working pressure of a scuba tank is, what happens when a valve shears off and and I would never place convenience over safety - my point is that the risk is minuscule, and the force of the impact required to shear off a tank valve is significant.

How did the accident occur? Was it front on? Sideways? Rear ended? Oblique? You furthermore assume that the tank will not be dislodged by the collision. What if you stack them your way, the tank is moved during the collision, hits a heavy metal part of the vehicle and is deflected enough to hit a passenger in your vehicle anyway?

Should we be concerned only about ourselves and not passengers in the vehicles behind us? What happens if the tank rockets into a school bus behind you? Would you, in hindsight, wish that you'd stacked the tanks a different way? What about securing them upright? Then the only direction it's going is into the road? Sooooooo many variables they cannot all be taken into account.

My reasoning is from experience working in the dive world - the fact that we have to transport hundreds of tanks per day, every day, by truck, car, minibus, whatever, or boats in high seas, and over the years there have indeed been some road accidents, (and some boat collisions, thanks captain!) tanks falling over and rolling around on deck, whatever - and the sum total of exactly zero tank rockets.

I'm not saying that it's impossible, I'm just saying that the risk is minuscule and cannot be eliminated completely, no matter which way you arrange your tanks. The best option is to make them secure as best you can, prevent them from rolling, moving or falling, and drive safely.

Cheers

C.

 

[Tropicalwolf]

Completely agree with Crowley. This is such a non-issue that I am surprised how often it comes up on SB.

 

[DevonDiver]

It the valve shears off then you'll have the tank that's shooting out, not the valve.

So, you think the valve just sits still? If so, you need to brush up on your basic physics.

Of course, getting hit by a valve is probably more survivable than getting hit by a tank. But both are going spoil your day....

Where a proper cylinder cage isn't available, I've always laid my cylinders with the valve facing rear. In the event of a forward collision, the valves won't get impacted if the cylinders slide forwards. In most vehicles I've used, it has been impractical to store the cylinders sideways.

 

[knowone]

Yep.

Or get your passengers to deliver the tanks in a VW Beetle.

 

[Sas]

I have them lying sideways in my boot. I have four in there usually and it just fits four, or two and my dive tub so I do not secure them in any other way.

I have been in a car accident with tanks in the boot. Was stationary and t-boned by another car, and the tank valves left deep imprints in the side of the boot but there was no damage to them. It's not a real concern of mine that the valves will fly off and cause damage.

 

[Tanked]

I lay them sideways but each tank facing opposite directions.

 

[2 Big 2 Fail]

Ah, yes. Such drama and agonizing over valves and tanks shooting around. How on Earth have all of us in fire and EMS survived all these years with SCBA and large and small oxygen tanks stowed in all sorts of positions?

It's really just another heavy object that could come loose in a tumbling crash and happen to land on your head if it's not tied down securely. Of course, the same could be said of driving cinder blocks home from the building supply or your new purchase from the Acme Anvil Company. And I suspect no one here ties those things down with heavy strap to a bolt set through a frame member.

 

[GrumpyOldGuy]

If you strap the tanks together, then even if a valve gets sheared off the mass of the other tanks should minimize the movement due to gas expansion. 2Big hits the nail on the head though, everything of even modest mass in a car that is not tied down becomes a potentially deadly projectile in a serious car accident, yet we typically give this minimal thought.

 

[Farback]

Ah, yes. Such drama and agonizing over valves and tanks shooting around. How on Earth have all of us in fire and EMS survived all these years with SCBA and large and small oxygen tanks stowed in all sorts of positions?

It's really just another heavy object that could come loose in a tumbling crash and happen to land on your head if it's not tied down securely. Of course, the same could be said of driving cinder blocks home from the building supply or your new purchase from the Acme Anvil Company. And I suspect no one here ties those things down with heavy strap to a bolt set through a frame member.

One of our neighboring departments had a pumper vs. logging truck incident a few years ago while responding to a call. Luckily, the crew survived, one FF had a broken leg, but the truck took a lot of damage. A racked SCBA bottle had the valve sheared off on impact but it stayed in the compartment. It beat the compartment up badly, but didn't escape the vehicle.

I used to worry about bottles more when I was a new diver, but a couple decades of firefighting has shown me what extremes a cylinder can withstand. High temp changes, landing on your back from a 'discretionary ejection from a flashover', and day to day use proves them to be very sturdy. We treat them with the respect due to a pressurized vessel, but don't treat them like a bottle of nitro.