By Graeme Davison
Many of us dive abroad and have to suffer the vagaries of the USA
system of cylinder capacities. The USA system is based around the capacity
of the cylinder (in cubic feet) at a defined operating pressure (in PSI).
The real problem comes from the changing operating capacities of the cylinders
(i.e. a 80 Cubic foot aluminium cylinder is rated at 3000 PSI, whereas
a 104 Cubic foot steel cylinder is rated at 2600 PSI) and the possibility
that a cylinder may not be pumped to its exact working pressure (due to
To make my life easier I sat down and calculated the following table,
which takes the USA standard cylinders and equates them to the water capacity
and operating pressure system we use in the Europe.