Commercial azoles benzotriazole (BZT) tolyltriazole (TTA) and butyl benzotriazole (BBZT) are well known yellow metal corrosion inhibitors for industrial water applications. BZT TTA and BBZT are all organic film forming species that coordinate and passivate the surface providing protection from corrosive species such as chlorides and sulfates which has been reported to be due to the stabilization of Cu(I) and providing a hydrophobic barrier on the surface. In this study the performance of BZT TTA and BBZT were analyzed based on their bulk corrosion properties mpy and electrode appearance in neutral pH synthetic cooling water under chlorination in beaker corrosion tests and recirculating units. ADM coupons from recirculating experiments with chlorination where evaluated against pre-filmed coupons utilizing XPS TOF-SIMS and IR and correlated to their bulk corrosion properties. The surface analysis of BZT TTA and BBZT under simulated cooling conditions provides new insights into the azoles’ corrosion inhibition performance mechanism and mode of use for yellow metal corrosion control.Copyright 2013 General Electric Company