Hello, We are looking at switching our supplier of 50% caustic to our plant. The new grade may contain up to 120ppm chloride ions whereas the old supply had a maximum of 20 ppm chloride ion. Although I am aware that chloride SCC is pretty much a non-issue at high pH levels (>12) with austenitic SS materials, I am wondering about the potential for pitting? Can pitting occur at such high pH levels such that we may see enhanced damage to SS components with the new caustic? I realize that the potential for pitting increases as pH drops but I could not find any data at high pH levels (>8). Also, we have steam traced carbon steel lines in service to transport this caustic at temperatures below 100F (but above freezing). Is there any reason to expect that this increase in chloride ion content may cause extra corrosion in the CS piping? Thanks, Metalbob