A method of forming a gas impermeable joint in a fluid system includes: providing
a tube having a metallic barrier layer disposed between an inner plastic layer
and an outer plastic layer; forcing at least one of the inner plastic layer and
the outer plastic layer into contact with a plastic surface of a component; and
welding the at least one of the inner plastic layer and the outer plastic layer
with the plastic surface to form the gas impermeable joint. The welding may include:
spin welding, hot plate welding, vibration welding, and ultrasonic welding. The
metallic barrier layer extends substantially to the component, thus improving the
gas impermeability of the joint between the tube and the component.
