ABSTRACT Conversion of marine tanker ships to fixed floating storage operation (FSO) installations may change the load and redundancy of marine boilers. Conversion may also change operation personnel experience and infrastructure due to differences in operating philosophy between tanker and FSO operations. These changes must be properly managed to avoid premature tube failures which may have more severe consequences than for tanker operation. This paper describes how conditions that promoted boiler tube failures were brought under control in a recently converted tanker.