Becht Engineering Blog

Integrity Operating Windows (IOWs) are a key component of a world class mechanical integrity program.   IOWs are not a new concept, as they have been around in different forms for many years.  However, with the publication of the first edition of API RP 584, Integrity Operating Windows , in 2014 and the more recent first edition of API 970, Corrosion Control Documents , in 2018, more focus has been placed on these limits within the refining industry. IOWs can be defined as established limits for process parameters that affect the integrity of equipment and piping when operations deviate from these limits.  API 584 defines IOWs in three categories: Critical – Parameters where rapid deterioration occurs when the limit is exceeded (typically hours to days) Standard – Parameter where exceedances over a specified period of time will cause increased degradation (typically weeks to months or within a turnaround interval) Informational –...