Undesired Effects of Relief Systems Concerns Mitigations

Process changes, MOC's, and lack of proper relief systems documentation are some reasons why relief systems may need to be revalidated during the life of a facility. When revalidating relief systems, concerns may be identified, such as improper relief device size, high inlet or outlet pressure drop, or unprotected equipment. Without expert knowledge of the various RAGAGEP related to relief systems, a seemingly simple fix may result in undesired consequences that may lead to a more dangerous situation than before. This paper goes into some examples of undesired effects of relief systems changes, including negative effects on upstream or downstream equipment, effects of changes in relief device set pressure, effects of changes in relief device type, and effects of piping changes.