Oxygen Barrier Packaging refers to active packaging systems used with foods, pharmaceuticals, electronic goods and various other items which help extend the shelf life, improve quality, improve safety and monitor freshness. Moisture control and oxygen control are used in packaging in which the contents need protection from the atmosphere within the packaging. Moisture control involves the use of desiccants which are a hydroscopic substance usually in the form of a porous pouch that is placed inside the packaging. They are used to reduce corrosion of machinery and to extend the shelf life of moisture sensitive foods and drugs. Oxygen scavengers or absorbers help remove oxygen from a closed package. Some are small packets of powdered iron and as the iron rusts the oxygen is removed from the surrounding atmosphere. However newer systems can be built into the package films or moulded structures which are specially manufactured to the products requirements. In this way the actual packaging itself becomes the oxygen barrier.