Industrial and other commercial facilities often require installing cathodic protection on non isolated structures such as chilled water lines, bare piping of various types and underground storage tanks. Often, because of the large amount of metal that is interconnected to the protected structures, the 100mV cathodic protection criterion is the only one that is practicable. This paper describes the testing required for this criterion, half cell placement, determination of the formation or decay of polarization and the accuracy of taking IR drop flee ("instant off') readings. Case histories concerning a large industrial plant, a gasoline service station and a sewage lift station are described
Keywords: cathodic protection criteria, gasoline service stations, industrial plants, one hundred mV polarization, retrofitting cathodic protection, sewage lift stations