Loading of refrigerated liquefied gases shall be carried out in such a manner as to ensure that unsatisfactory temperature gradients do not occur in any cargo tank, piping or other ancillary equipment. When determining the holding time (as described in 7.2.4.16.17), it shall be assured that the degree of filling does not exceed 98% in order to prevent the safety valves from opening when the tank is in liquid full condition. When refrigerated liquefied gases are carried using a system according to 9.3.1.24.1 (b) or 9.3.1.24.1 (c), a refrigeration system is not required. In the case of UN No. 2187 'CARBON DIOXIDE, REFRIGERATED LIQUID', this provision applies when the possibility of solidification shall be avoided. To ensure the product remains in the liquid phase, the temperature shall be kept at 15 C above the solidification temperature at the required pressure during the transport. The transport document shall contain a notice on the avoidance of solidification of the product.
