This publication provides recommendations for water chemistry monitoring and is a companion to the ASME "Consensus on Operating Practices for the Control of Feedwater and Boiler Water Chemistry in Modern Industrial Boilers," "A Practical Guide to Avoiding Steam Purity Problems in the Industrial Plant," and "Consensus on Operating Practices for Control of Water and Steam Chemistry in Combined Cycle and Cogeneration Power Plants."These documents provide guidance for avoiding the penalties of severe corrosion or deposition in steam generation systems and end user equipment.