There are three purposes for the prevention of damage to persons, vessels and cargo, namely:
· Dehumidification, specifically to reduce relative humidity, namely to avoid dew or sweat, while some goods are damp, mildew, heat and spontaneous combustion, and accelerate corruption;
· Cooling, which has the same effect as "wetting";
· Remove hazardous gases and provide fresh air to prevent explosions and poisoning accidents.