The invention relates to a cleanroom-capable coating system for PVD or CVD processes having at least one vacuum coating chamber, in which vitreous, glass-ceramic and/or ceramic layers deposited. A first opening of the vacuum coating chamber is connected via a separately evacuable vacuum airlock chamber (load lock) to a cleanroom, the vacuum airlock chamber comprising transport means for delivering substrates into the vacuum coating chamber and for taking substrates out of the vacuum coating chamber, and a second opening of the vacuum coating chamber connects the vacuum coating chamber to a grayroom area separated from the cleanroom.