Chromium Car

Maintaining a bath surface tension less than 35 dynes/cm requires frequent cycle of treating the bath by a wetting agent and confirming the effect on surface tension. Traditionally surface tension is measured by a stalagmometer. This method is, however, tedious and suffers from inaccuracy (errors up 22 dynes/cm has been reported), and is dependent on user's experience and capabilities.
Additional toxic waste that is created from hexavalent chromium baths include lead chromates which form in the bath because lead anodes are used. Barium is also used to control the sulfate concentration, which leads to the formation of barium sulfate, a hazardous waste.