(13b) Application of Quantitative Risk Analysis to Fireproofing

One of the core elements of fire protection for petrochemical processing plants is the consideration of passive fire protection (PFP). This general category, often referred to as fireproofing, is addressed in the American Petroleum Institute (API) recommended practice (RP) 2218. This RP provides guidelines for selection and application of fireproofing with what is mostly a qualitative risk assessment approach. The logic focuses on predicting pool fires based on a rough characterization of system properties combined with equipment layout. Pool fire impacts are generally confined to the immediate area around and above the pool location. In contrast, jet fires are highly directional, can affect areas that are significantly removed from the release location, and will vary over time due to pressure decay and system response. After the Piper Alpha incident and other events, the industry has given more attention to jet fire hazards as a critical piece of an effective fire protection analysis. API 2218 addresses jet fires in an appendix due to their unpredictable nature, leaving the basis for structural fireproofing to pool fire exposures. To properly account for both fire types, fire exposure can be evaluated with quantitative risk analysis (QRA) tools that incorporate both jet and pool fire impacts for a wide variety of accident scenarios, weather conditions, and release orientations. By evaluating the thermal radiation impacts of fires in relation to the vulnerability of steel structural elements, a QRA-based approach to placement of PFP can be achieved. This approach has the benefit of applying PFP where it is needed the most, to best protect a company’s infrastructure.