When selecting a pipeline coating, the "Fail Safe" characteristics may be more important than other issues that are normally considered. A "Fail Safe" coating system is defined as one that will allow cathodic protection (CP) current to pass through it to protect the substrate - not shield it - should the coating bond fail and adequate CP is available (Norsworthy, June 2004). Therefore, "Fail Safe" coatings will reduce or eliminate corrosion, including stress corrosion cracking (SCC), on the pipe under the coating if a bond failure occurs, water penetrates and cathodic protection is adequate.
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