121. Prior to the first shipment of any package, the following requirements shall be fulfilled:
(a) if the design pressure of the containment system exceeds 35 kPa, the consignor shall ensure that the containment system of the package conforms to the approved design requirements relating to the capability of that system to maintain its integrity under that pressure;
(a) for each Type B(U), Type B(M), Type C package and for each package containing fissile material, the consignor shall ensure that the effectiveness of its shielding and containment and, where necessary, the heat transfer characteristics and the effectiveness of the confinement system are within the limits applicable to or specified for the approved design; and
(b) for package containing fissile material, where neutron poisons are included as components of the package, the consignor shall check to confirm the presence and distribution of those neutron poisons.