(129a) The Flow Method: An Improved HAZOP Methodology

The traditional Hazard and Operability Study (HAZOP) is a well-established methodology in the Chemical Process Industry for hazard identification and risk analysis, also referred to as Process Hazard Analysis (PHA). However, its deviation-based approach can lead to inefficiencies, fragmented reviews, and increased team fatigue. The Process Flow Failure Modes Analysis (PFFM) was introduced as an efficient alternative, evaluating risk based on the natural flow of the process, and recognizing that each piece of equipment has consistent and knowable failure modes. However, PFFM's limitations include the intensive preparation required and the qualitative nature of the evaluation, which leaves the potential for missed risks. Layer of Protection Analysis (LOPA), a more quantitative method, typically relies on HAZOP results for its risk evaluation, which increases team resource usage.

This paper introduces the "Flow Method," an evolved and optimized blend of HAZOP, PFFM, and LOPA. By integrating additional tools, the Flow Method enhances the overall PHA process, resulting in more streamlined, and consistent studies with unparalleled thoroughness.

With over 200 studies conducted across 15 production sites, and 10 wholesale terminals, Nutrien Inc. has now adopted the Flow Method for all PHA studies. This paper presents comparative data from multiple studies and locations, demonstrating the Flow Method's effectiveness and its potential to revolutionize process safety analysis in the chemical industry.