Revised in 2020!  Assessment of corrosion in the field is complex because of the variety of applications, process conditions, and fluid phases that exist in industrial plants where corrosion occurs.  A wide range of direct and indirect measurement techniques is available, but each technique has its strengths and weaknesses.  In some applications, certain techniques cannot be used.  Some techniques can be used online, while others are used off-line.  Commonly, more than one technique is used so the weaknesses of one are compensated for by the strengths of another.  In other cases, a combination of different techniques can be synergistic, such as process sampling along with detection of corrosion upset.

The purpose of this technical committee report is to analyze the various techniques with respect to their benefits and limitations across the broad spectrum of industries in which they are used.

This revision incorporates Guided Wave Monitoring (GWM), On-Line Gas Chromatography (GC), and Acoustic Solid Detection (ASD) techniques and updates references to NACE standards.

This technical report applies to water-using cooling and heating systems in buildings.  It provides information for minimizing system damage and operational interference because of corrosion, scale, fouling, and microbiological growth in building heating, ventilation, and air conditioning (HVAC) systems.  This includes open and closed circulating water systems, low-pressure steam boilers and hot water “boilers.”  The document also addresses thermal energy storage systems, but does not address potable water or fire protection systems.  It is intended for use by building owners and engineering, maintenance, and operations management personnel.  It is also intended for use by those involved in the design and construction of building HVAC systems so that corrosion, scale, fouling, and microbiological growth problems described above can be understood, anticipated, and minimized through appropriate design decisions.