either or

[WD8CDH]

It depends on where you are and what your specific needs are. Filling LP tanks to 3000-3500 psi is common in cave country and in many wreck diving destinations. Steel tanks are hydro'd to 5/3rds of their working pressure and with 2640 tanks that's 4400 psi. They are designed to withstand this for 1000's of cycles. The same tanks in Europe are rated to 4000psi and they do not use burst discs in many countires. <snip>QUOTE]

That statement about Euro tanks is absolutely false. The Euro tanks that are rated to 4000psi have either thicker walls or stronger steel or both. They are not the same tank. If you check with the manufacturer (e.g. Faber), you will see that they don't even weigh the same.