Not all mixed metal oxide (MMO) coated titanium anodes are the same. MMO coatings have
different compositions, some of which perform better for specific applications. Certain
environments can cause increased wear rates or anode fouling. The performance of iridium oxide
and ruthenium oxide coatings are compared. In addition to the coating, preparation of the titanium
substrate, application of the coating, lead wire insulation, electrical connection and quality control
procedures have substantial impact on anode performance and life. Case histories for underground
conventional and concrete cathodic protection applications are included.