[fox46]

Although your suggestion of a sock sounds pretty good, what about versions of the mesh bags used to contain onions and other similar vegetables? (Those might be easier to incorporate into existing designs.)

My thoughts around using the sock was that they would be elastic and absorb the energy of an expanding tank while allowing the compressed air to permeate the fabric and release pressure. The onion bag idea could work as well but are they not a relatively non-elastic material?

Would it make it safer to put a wrapping of duct tape around them

I think since the duct tape would be wrapped around the tank tightly it would tear as the tank expanded. I feel it would also contain the compressed gas which could cause it in itself to burst like a balloon.