Define specific failure events (e.g., catastrophic catastrophic tank rupture vs. a 10mm pipe puncture).
Identifies the exact process units driving facility risk, ensuring safety budgets target high-risk areas.
| Risk Level | Technique (from Guidelines) | When to Use | | :--- | :--- | :--- | | | Check-List/HAZOP | Non-flammable, low-toxicity fluids. | | Medium | LOPA (Layer of Protection Analysis) | SIS design (IEC 61511) or single unit. | | High | Full QRA (Event Trees + Consequences) | New technology, LNG terminals, large Cl2 storage. | Define specific failure events (e
Calculate release rates, total mass spilled, and phase changes (vapor, liquid, or two-phase flash).
High-quality data is essential for a "defensible" risk analysis. Process Data: P&IDs, heat and material balances, and chemical properties. Site Data: | Risk Level | Technique (from Guidelines) |
Problem: You finish the report and never update it. Guideline Solution: Chapter 17 (Management of Change). The guidelines require a (typically every 5 years or after a major incident).
A tracking sheet to record the exact inputs and outputs of modeling software. This includes release rates, flash fractions, downwind toxic distances, and explosion overpressure radii. Document 4: Risk Mitigation Action Tracker | Calculate release rates, total mass spilled, and
Individual risk measures the probability that a specific person at a defined location will suffer a defined level of injury (usually fatality) over a specific time period (typically per year). This is visually represented using mapped over facility layouts, showing geographical risk boundaries. Societal Risk
The second edition of the Guidelines for Chemical Process Quantitative Risk Analysis (the most widely distributed and cited version) is structured to walk a practitioner through every stage of a risk analysis. The table of contents reveals why this text is the industry standard, spanning approximately 784 pages of critical data:
Use techniques like HAZOP (Hazard and Operability Study) or FMEA (Failure Modes and Effects Analysis). Identify "Loss of Containment" (LOC) scenarios.
Since this is an industry standard reference, there are three main ways to access the full text: