What is a Process Hazard Analysis (PHA) and name two common methodologies?

• A. A PHA is a financial risk assessment; common methods include Monte Carlo.
• B. A PHA is a routine safety inspection; methods: checklists.
• C. A PHA is a hazard assessment focusing on equipment reliability; methods: FMEA and FTA.
• D. A PHA systematically identifies hazards and assesses risk; common methods include HAZOP and What-If/Checklist.

Answer: (D)

Process Hazard Analysis is a structured, systematic examination of a chemical process to identify potential hazards and evaluate the risks they pose to people, property, and the environment. It looks at how combinations of equipment, materials, operating modes, and human factors could lead to unwanted events and what controls are in place or needed to reduce those risks. This goes beyond a financial risk assessment, a routine safety inspection, or a narrow focus on equipment reliability.

Two common methodologies used in PHA are HAZOP and What-If/Checklist. HAZOP is a team-based study that analyzes the process design in sections (nodes) and uses guide words like “no,” “more,” or “less” to explore deviations from the intended design, uncovering potential causes, consequences, and safeguards. What-If/Checklist uses structured prompts to brainstorm potential hazards and their impacts, often weaving in industry experience and historical incidents. Both approaches aim to systematically identify hazards and assess risk to determine where safeguards or actions are needed.