scuba tanks in my car trunk.

[Troutmaster]

Unless you're carrying shape charges attached to full tanks in your car, you really have nothing to worry about.

-Charles

I always put the tanks in the trunk, the shape charges in the back seat and the blasting caps in the glove box, just to be safe.

 

[wadedeeper]

Actually this is rather on the top range of what you can expect. AL80 is hydro tested to 5000 PSI (I think). If I remember burst disk is at 4000 PSI so the temperature in car would need to reach 244F.

Iztok already made the point of the heat...and honestly I have left my tanks in the car every day in Southern California with temps outside reaching easily in the low 100's with no problem. Mainly because I dove before work or plan to dive after work.

My main concern has always been a car accident or the tanks rolling and breaking the valve/1st stage enough to rocket the tank out in whatever direction it feels. I would worry about that before heat...but not much you can do other than stand the tanks upright and strap them in like they do on the tanker trucks that carry numerous bottles.

 

[seaducer]

I always put the tanks in the trunk, the shape charges in the back seat and the blasting caps in the glove box, just to be safe.

If those are electrical blasting caps I hope you have them in a static proof bag, because the glove box is uncomfortably close to the radio.

For my money, I would be more worried about theft leaving my stuff in a car for hours on end. When I plan to dive right after work I bring most of my gear into my office. But then I live in Jersey...maybe I am paranoid

 

[NeedABiggerBoat]

I had my hp130 filled at my LDS, and someone put it out in the sun. Within 5 minutes the neck-seal blew and was leaking air. I was amazed that the neck o-ring could actually be blown up and out of the neck like that.

 

[supajaydub]

I'm surprised that nobody has thought of the fact that the air temperature is only 1 factor in this equation here.

To be absolutely correct you would need to look into the heat transfer from the ambient air, through the tank material and then to the gas inside. This would take into account conduction and radiation heat transfer mechanisms, since I'm hoping most people don't put their tanks in front of some hot flowing gas of some sort that would bring convection into play.

I'd need to go blow the dust off my heat transfer and thermodynamics text books to find the exact answer for you all but I'm sure you all know this already.

 

[JohnB47]

Heat transfer would only matter if you are trying to calculate how long it will take for you burst disk to blow. It is very unlikely that leaving your tanks in the trunk will cause the tank to explode, but old disks do fail. And if your valve is not torqued properly, or your neck o-ring is old, the o-ring can fail. Neither of these will cause anything catastrophic to happen, although you will lose the air fill.

 

[charlesml3]

breaking the valve/1st stage enough to rocket the tank out in whatever direction it feels.

"Rocket the tank out" isn't really what happens. Yea, the air vents quickly and the tank can get moving but it's not like it's going to punch through the side of your car or anything. Back to the Mythbusters episode: They shot a hole through the bottom of an AL80 and the escaping air barely had enough force to hold the tank into the upper corner of the shipping container.

There was another Mythbusters where they broke the neck off of a much larger tank sitting on it's side. The tank slid along the floor for about 40 feet and gained some considerable momentum before punching through a single layer cinder block wall. It was really the momentum of the heavy tank that did punched through.

-Charles

 

[Johan Broere]

My instructor was a bit paranoid about this. Even at the beach he was afraid for tanks laying in the sun. Ofcourse on the dive boat they are standing in the sun all day. I really thought there would be more bad experiences out there. I feel much better now. Let the sun shine and happy diving. Thanks to all, Johan.