|If actively ventilated containers are available, which is becoming rare, relatively large quantities of water may enter the container as a result of excessively moist air being used for ventilation. If air is changed four times per hour, 1,060.5 m³ of air are passed through an identically sized container in eight hours of ventilation. If this air, at a temperature of 25°C and a relative humidity of 90%, meets with a cargo at 15°C, it cools down on the cargo and could theoretically deposit 9,757 kg of water, or almost 16 times as much. In practice, not the entire quantity of water will be condensed out, since the cargo warms up slowly and the air introduced does not mix very well and is therefore not completely cooled down.
A theoretical examination reveals very clearly the moisture potential of active ventilation.