PSM Challenges in an Aging Cyanide Plant

A 40-year old hydrogen cyanide (HCN) plant is examined as a case study. The plant is approximately 90% PSM-covered, predates PSM by over a decade, and has a large dichotomy in experience level. Despite the challenges of being designed before the law was written, the plant has one of the best safety records in the company. In the past five years, heightened company safety requirements have required the unit to implement new technologies, particularly with Safety Instrumented Systems (SIS). The handover of new technology to a workforce with changing age and experience demographics has been especially challenging. This study examines the plant’s practices and execution through infrequent turnarounds, scheduling of Mechanical Integrity inspections, and other topics.