The apparatus comprises a double walled vacuum insulated vessel defining a
cryogen space for holding a cryogenic fluid, a pump assembly comprising a
pump with a suction inlet disposed within the cryogen space, and at least
one elongated member extending from the pump to a drive unit disposed
outside the cryogen space. The elongated member comprises an elongated
non-metallic section that has a thermal conductivity that is less than
that of a structurally equivalent elongated stainless steel member of the
same length. In preferred embodiments, the elongated member can be one or
both of a drive shaft or a rigid structural member for supporting the
pump and holding it in a fixed relationship to the drive unit. The method
employs the apparatus to increase hold times for holding cryogenic fluids
by reducing heat leak into the cryogen space.