In order to achieve consistent cleaning results, the user has to ensure that the actual concentration of the cleaning agent stays within the recommended application range. Various factors such as “drag-out”, dilution and evaporation can potentially influence the actual concentration. Regular measurements of all process related parameters are therefore highly recommended. The ZESTRON Bath Analyzer 10 is a simple, easy-to-use method which provides reliable and accurate results for fresh as well as for contaminated cleaning baths.