- On the cargo information pages, ventilation is discussed in association with storage climate conditions (see Section 11.3). For many hygroscopic goods, including their packaging, with a low water content (WCC 2) and 3rd or 2nd order biotic activity (BA 3 or BA 2), storage climate conditions VI are recommended, i.e. temperature, humidity/moisture and possibly ventilation conditions. This means that ventilation is not required where the goods are container dry. If goods, packaging, accompanying material and dunnage are too damp, ventilation is absolutely essential if the necessary temperature and humidity/moisture parameters are to be achieved. Since this is impossible in standard containers, damage will have to be expected from the outset with cargo which is not container dry.
- If a container is packed with craft items in a damp season, for example, there is a risk of mold growth. This risk may be prevented by "ventilated" packaging, the cartons or plastic bags being perforated, i.e. provided with holes. The openings in the sales packaging have then to coincide with the openings in the transport packaging, so that moist warm air can escape from the packaging and air exchange can take place. To be able to achieve a ventilation effect when a container is loaded with cartons, ventilated containers have to be used. Since the ventilation openings have in each case to be located in the end faces of the cartons, the cartons have to be stowed with the ventilation holes in their ends crosswise in the container. The risk of mold due to humidity/moisture can be greatly reduced by shipping packaged hygroscopic goods in ventilated cartons.
- In the case of hygroscopic goods of low water content (WCC 2) and 2nd order biotic activity (BA 2), such as green coffee beans, raw cocoa and shell fruit (nuts), ventilated containers are recommended, among other things to prevent the risk of postfermentation and self-heating. Care is taken to ensure that a vigorous air flow is provided to remove heat, water vapor and respiratory gases on the one hand and to supply oxygen on the other. So that the cold air flow does not cause chilling to below dew point in the winter months and thereby cause sweat to form, particular care must be taken with the ventilation measures.
- In the case of highly perishable goods in refrigerated containers, for instance fruit and vegetables with their high water content (WCC 3) and high, 2nd order biotic activity (BA 2), the cargo information pages indicate not only storage climate conditions, i.e. temperature, humidity/moisture and ventilation conditions (SC VII) (temperature-controlled transport) but also the air exchange rate/hour, so as on the one hand to supply the goods of vegetable origin with atmospheric oxygen and on the other hand to remove harmful respiratory products, such as carbon dioxide and ethylene. Inadequate ventilation may result in fermentation and rotting of the fruit as a result of increased carbon dioxide levels and inadequate supply of atmospheric oxygen.
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