Managing SOS, POS and MOS to Minimize Major Incidents

摘要

This paper looks at some of the incidents that have occurred in ammonia plants and the hydrocarbon industry, and discusses the breakdowns in the safety management system which caused such incidents. The failures related to Start-up Override Switch/System, Process Override Switch/System and Maintenance Override Switch/System are essentially systematic failures and hence a robust audit and verification system is necessary to prevent these failures. A brief description of interlock configurations is included This paper also discusses some of the nuances associated with the interlock configuration, immediate causes including scope creep and root causes of failures, practices currently undertaken in many of plants and new solutions.