A type of dampening system found on some printing presses used in web offset lithography, comsisting of a row of nozzles which spray a fine mist of fountain solution onto the inking rollers. A spray-bar system is often used in lieu of a conventional roller-oriented dampening system. Its advantages include more accurate dampening control, as the spray of each nozzle across the width of the press can be individually set. There is also no recirculation—and thus no contamination—of the fountain solution with this system. One drawback, however, is that some fountain solution ingredients can contaminate and/or clog the nozzles. Some types of spray-bar dampening systems may require their own set of rollers connected to the inking rollers. (See DampeningSystem.)
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