Leveraging PSM to Implement Key Elements of a SIS Program

The International Electrotechnical Commission (IEC) 61511 standard, “Functional Safety – Safety Instrumented Systems for the Process Industry Sector", has achieved wide acceptance within the process sector, including chemicals, oil refining, oil and gas production, pulp and paper, and non-nuclear power generation. Currently, the nineteen (19) clauses comprising the IEC standard are being implemented to varying degrees within these industries. For example, development of a Safety Requirements Specification is a mature effort within the sector, while complying with the requirements for Functional Safety Assessments is often a struggle for many companies. Implementing the softer aspects of IEC 61511 by leveraging complementary elements within Occupational Safety and Health Administration's (OSHA's) Process Safety Management (PSM) regulation, 29 CFR 1910.119, can avoid duplication of effort at a facility. Specifically, the cross-over elements from PSM, relevant to the development and management of an IEC compliant program for Safety Instrumented Systems (SIS), include Process Hazard Analysis (PHA), Process Safety Information (PSI), operating procedures, Pre-Startup Safety Review (PSSR), Mechanical Integrity (MI) and Management of Change (MOC). Each PSM element is presented in this paper from a functional safety implementation perspective to demonstrate the benefits of utilizing existing site PSM components to comply with the associated clauses of the IEC 61511 standard. Merging overlapping requirements from OSHA and IEC can then result in the improved facilitation of SIS audits and gap assessments, along with increased information flow between organizational groups responsible for SIS and PSM.