Reliability and Integrity Assessment of High Integrity Pressure Protection Systems (HIPPS) Considering Common Cause Failures Using the Multiple Beta Factor Model

Abstract

High Integrity Pressure Protection Systems (HIPPS) are critical safety instrumented systems used in high-risk industries to prevent over-pressurization and mitigate hazardous events. The reliability and integrity of these systems are essential for ensuring safe operation and achieving required Safety Integrity Levels (SIL). However, their performance is often compromised by design deficiencies, inadequate maintenance practices, operational errors, and the presence of Common Cause Failures (CCFs), which can simultaneously affect redundant components and significantly reduce system effectiveness. This study presents a comprehensive reliability and integrity assessment of HIPPS by incorporating Common Cause Failures using the Multiple Beta Factor (MBF) model. The research analyzed both functional performance and failure behavior of HIPPS through an advanced reliability modeling approach. A simulation model was developed in MATLAB/Simulink to evaluate system performance while accounting for multiple dependent failure mechanisms. The MBF method was employed to provide a more realistic representation of CCFs by distributing failure probabilities across different failure groupings, thereby improving the accuracy of reliability predictions compared to conventional single beta-factor models. Results obtained from the simulation and analysis reveal that inadequate design processes contribute to approximately 25% increase in system failure likelihood, while poor maintenance practices account for about 35% increase in failure risk. Operational errors were found to contribute to 20% of total failures, whereas environmental factors, such as temperature extremes, resulted in a 15% increase in component degradation rates. Furthermore, the incorporation of real-time monitoring and diagnostics was shown to improve overall system reliability by reducing potential failure modes by up to 40%.The study concludes that integrating CCF considerations using the MBF model significantly enhances the accuracy of HIPPS reliability and integrity assessment. It further emphasizes that improvements in system design, implementation of robust maintenance strategies, enhanced operator training, and adoption of advanced monitoring technologies are essential for minimizing failure risks. The findings provide valuable insights for engineers and safety professionals aiming to optimize HIPPS performance, thereby contributing to safer and more efficient operation of high-pressure industrial systems.