The bases for determining the qualifications of boiler and process operators in the refining and petrochemical industry should be their knowledge of the process unit operating manual and satisfactory completion of both on-the-job and related training. To be fully authoritative as a document@ it is essential that all information contained in these operating manuals be maintained in an accurate and up-to-date condition. Each operating manual should include a preface emphasizing the fact that in the training and qualifying of process operators@ a systems approach rather than a component approach is utilized. Vessels@ tanks@ drums@ piping@ heat exchangers@ reactors@ steam generators@ and so forth are components of a total process system; therefore@ training and qualifications to operate the system must include the necessary qualifications to operate the individual components which make up@ and are part of@ the total process system.