Vapor Barrier Packing involves enclosing electronic items or parts with extremely sensitive metal surfaces in a water-vapor-proof foil barrier. The items are cushioned and activated desiccant is placed in the bag prior to sealing all seams. One corner of the bag is left open and a vacuum is used to remove excess air and the opening sealed. Packing in this method reduces the humidity inside the barrier to very low levels.

This method of protection is particularly important for sensitive items that are being shipped via ocean transport where salt-laden moisture could invade and jeopardize product integrity.

When items are packed in this method for military packaging, humidity indicator cards are placed inside the bag and this area is marked for opening at periodic intervals to check the condition of the desiccant. Humidity indicator plugs that protrude through the foil barrier are also available so that so the barrier does not have to be opened to check the desiccant status.

Vapor Barrier Packing protects the items within the foil barrier for twelve to eighteen months. Chick uses different foil materials from standard polyethylene-foil-polyethylene on lighter items to scrim-foil-nylon for large items such as generators weighing hundreds of thousands of pounds.

*(AKA: Vacuum Packing, Vapor Packing, Method II, Method 50)