Container Rain

Dew Point Mechanism

Diurnal temperature variations during long voyages drive the continuous cycle of evaporation and condensation. As the shipping vessel crosses different climate zones, the warm air inside the metal container holds high amounts of moisture evaporated from wooden pallets and textile goods. When night temperatures drop, the container walls cool rapidly, causing the humid air to condense on the ceiling.

This condensed water accumulates until gravity pulls the drops down onto the cargo below.

Prevention Method

Logistics managers use high-capacity desiccants and proper container liners to protect dry apparel shipments. Placing calcium chloride bags throughout the container lowers the relative humidity of the internal air. Liners wrapped around the cargo block droplets from making contact with the boxes.

Financial Outcome

Moisture-damaged garments are unfit for retail shelves and usually require total destruction. Insurance providers require temperature and humidity logs to approve claims filed for cargo ruined by condensation during transit. Brands suffer lost sales when entire seasons of stock are lost to mould.