Concrete is used in power facilities, chemical processing plants, pulp and paper mills, petrochemical plants, water and wastewater treatment plants, food and beverage plants, and mining operations. Concrete frequently provides structural support for steel in industrial applications; it is also used for catch basins, troughs, machinery mounts, spill containment, and immersion service. Concrete, unlike steel, is not a predictable, uniform substrate. Concrete is very porous and in many industrial exposures is likely to absorb chemical contamination and water, which can cause spalling and eventually loss of structural integrity. When providing corrosion protection for concrete substrates, consideration must be given to the use of liquid, organic, chemical-resistant coatings and their proper application and inspection. This standard recommended practice sets forth guidelines for the application of quality protective coating systems to properly prepared concrete surfaces. Information contained herein is intended as a guide for personnel who prepare specifications, standards, and procedures for the coating or lining of concrete surfaces. The information provided in this standard is based on the best current knowledge and experience of committee members and not necessarily on reproducible scientific evidence. This standard was originally prepared in 1992 by NACE Task Group T-6A-59 on Coatings/Linings over Concrete for Immersion Service, which was a component of Unit Committee T-6A on Coating and Lining Materials for Immersion Service. It was technically revised in 2001 by Task Group (TG) 141. This Task Group is administered by Specific Technology Group (STG) 03 on Protective Coatings and Linings??Immersion Service. This standard is published by NACE International under the auspices of STG 03.