It seems like instrument maintenance (and maintenance in general) is a bit overlooked when people consider process safety.
Even though mechanical integrity is a cornerstone of OSHA’s 1910.119 process safety management (PSM) regulations, maintenance in general does not always play a big part in process hazard analyses (PHA) such as hazard & operability (HAZOP) studies and risk assessments such as layer-of-protection analysis (LOPA), other than failure of process equipment and instrumentation being considered as hazard-initiating causes in the analysis. There may be a guideword or two, but HAZOP and LOPA are scenario-based, whereas maintenance, reliability, and mechanical integrity are system-level safety considerations that must be considered holistically. Maintenance, it seems, is often taken for granted, yet it can have a significant effect on safety.
This article explores how process safety is affected by system-level considerations in the instrument maintenance program; reviews how instrument maintenance has affected and can affect process safety, organizational performance excellence, and the minimum required maintenance level (MRML); and identifies signs of a poorly performing instrument maintenance organization.