NBN EN 1968:2002

This European Standard specifies the requirements for periodic inspection and testing of seamless steel transportable gas cylinders (single or those from bundles) intended for compressed and liquefied gases under pressure, of water capacity from 0,5 l up to 150 l.
NOTE As far as practicable, this standard may also be applied to cylinders of less than 0,5 l water capacity.
This standard specifies the requirements for periodic inspection and testing to verify the integrity of such gas cylinders to be reintroduced into service for a further period of time. It also defines a procedure to qualify existing gas cylinders for free movement between member states of the European Union (see annex A).
This standard does not apply to periodic inspection and testing of acetylene cylinders or composite (fully wrapped or hoop-wrapped) steel cylinders.