1. The cause of container rain: Normally in the container, a temperature change of 5-10 ℃ can cause container rain. Water vapor will condense on the surface of the coldest object, usually on the ceiling of the container and around the cargo. If the liquid water drops on the cargo, it will cause corrosion and mold.

2. Harm of container rain: Even if there is no condensation, it will cause damage to the goods under long-term high humidity. Under the condition of 60% to 70% humidity, many metal parts will rust and discolor. At more than 80% humidity, fungus grows, the label falls off, and the carton begins to soften.