While various standardized tests exist for evaluating the solubility of water heater enamels:  (1) US military WH196J (equivalent to AS/NZS 4692), (2) CSA C309 patch tank testing, (3) DIN4753-3, there is no harmonized standard (such as with ASTM) for the US market.  A benchmark study was conducted on different manufacturers of enameled hot water tanks to establish a baseline of the solubility of water heater enamels currently used in the US market.​  The enamel water resistance was assessed using the procedures U.S. Military WH196J Boiling Sodium Bicarbonate Solution​ and Canada CSA C309 “Patch Test”.  The benchmark results were compared to enamels produced for different regions globally to determine which procedure could be the most suitable accelerated test standard for the US market.