Packing and reinforcement must be secure and capable of maintaining the shipment in a totally leak-proof condition, in atmospheric pressure and withstanding temperature variations during flight.

All containers must be constructed of good quality waterproof materials and must be rigid enough to withstand any stacking levels.

Bags or sacks must be water resistant and made tight to prevent shifting of contents during transportation. Receptacles must always be securely closed to prevent loss of content. 

Receptacles of liquids must not be entirely full. About 20 percent of the receptacle’s height must be left vacant to prevent leakage of contents from an increase of temperature during transportation.