A process used particularly for the impregnation of dry timbers that must retain dimensional accuracy for use in class 3 as windows and door frames, etc. However, other ranges such as constructional timber, cladding boards, wooden balconies, etc., are also treated in the double vacuum process.Vacuum chamber machines are machines that seal food in a plastic bag for preservation. They have strong vacuuming power to remove the air from food in the plastic bag and are often used in commercial kitchens, although there are bench top models which are used in homes.

A vacuum packaging machine puts product in a film bag, de-aerates the bag by decreased pressure in a vacuum chamber, and seals the bag. It prevents discoloring of product and heightens display effect. To avoid smashing, those with a gas-inflating function are available.